Patran 2008 r1 Reference Manual Part 2: Geometry Modeling

Patran 2008 r1

Reference ManualPart 2: Geometry Modeling

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Con t en t s

Geometry Modeling - Reference Manual Part 2 dÉçãÉíêó=jçÇÉäáåÖÉêÉåÅÉ=j~åì~ä=m~ê

1 Introduction to Geometry Modeling

Overview of Capabilities 2

Concepts and Definitions 4

Parameterization 4

Topology 10

Connectivity 16

Effects of Parameterization, Connectivity and Topology in Patran 18

Global Model Tolerance & Geometry 19

Types of Geometry in Patran 20

Trimmed Surfaces 20

Solids 24

Parametric Cubic Geometry 25

Matrix of Geometry Types Created 27

Building An Optimal Geometry Model 31

Building a Congruent Model 31

Building Optimal Surfaces 33

Decomposing Trimmed Surfaces 38

Building B-rep Solids 41

Building Degenerate Surfaces and Solids 42

2 Accessing, Importing & Exporting Geometry

Overview 46

Direct Geometry Access of CAD Geometry 47

Accessing Geometry Using Patran Unigraphics 47

Accessing Geometry Using Patran ProENGINEER 54

PATRAN 2 Neutral File Support For Parametric Cubic Geometry 57

3 Coordinate Frames

Coordinate Frame Definitions 60

Geometry Modeling - Reference Manual Part 2

==

iv

Overview of Create Methods For Coordinate Frames 64

Translating or Scaling Geometry Using Curvilinear Coordinate Frames

67

4 Create Actions

Overview of Geometry Create Action 72

Creating Points, Curves, Surfaces and Solids 78

Create Points at XYZ Coordinates or Point Locations (XYZ Method) 78

Create Point ArcCenter 82

Extracting Points= 84

Interpolating Points 94

Intersecting Two Entities to Create Points 100

Creating Points by Offsetting a Specified Distance 110

Piercing Curves Through Surfaces to Create Points 112

Projecting Points Onto Surfaces or Faces 115

Creating Curves Between Points 120

Creating Arced Curves (Arc3Point Method) 130

Creating Chained Curves 133

Creating Conic Curves 135

Extracting Curves From Surfaces 139

Creating Fillet Curves 145

Fitting Curves Through a Set of Points 149

Creating Curves at Intersections 151

Manifold Curves Onto a Surface 161

Creating Curves Normally Between a Point and a Curve (Normal Method)

168

Creating Offset Curves 171

Projecting Curves Onto Surfaces 176

Creating Piecewise Linear Curves 183

Creating Spline Curves 185

Creating Curves Tangent Between Two Curves (TanCurve Method) 193

Creating Curves Tangent Between Curves and Points (TanPoint Method)

195

Creating Curves, Surfaces and Solids Through a Vector Length (XYZ Method)

199

Creating Involute Curves 203

Revolving Curves, Surfaces and Solids 208

Creating Orthogonal Curves (2D Normal Method) 214

Creating 2D Circle Curves 222

Creating 2D ArcAngle Curves 226

Creating Arced Curves in a Plane (2D Arc2Point Method) 229

vCONTENTS

Creating Arced Curves in a Plane (2D Arc3Point Method) 237

Creating Surfaces from Curves 240

Creating Composite Surfaces 250

Decomposing Trimmed Surfaces 254

Creating Surfaces from Edges (Edge Method) 256

Extracting Surfaces 259

Creating Fillet Surfaces 265

Matching Adjacent Surfaces 269

Creating Constant Offset Surface 271

Creating Ruled Surfaces 273

Creating Trimmed Surfaces 277

Creating Surfaces From Vertices (Vertex Method) 286

Extruding Surfaces and Solids 288

Gliding Surfaces 293

Creating Surfaces and Solids Using the Normal Method 297

Creating Surfaces from a Surface Mesh (Mesh Method) 304

Creating Midsurfaces 306

Creating Solid Primitives 311

Creating a Solid Block 311

Creating Solids from Surfaces (Surface Method) 327

Creating a Boundary Representation (B-rep) Solid 337

Creating a Decomposed Solid 339

Creating Solids from Faces 342

Creating Solids from Vertices (Vertex Method) 345

Gliding Solids 347

Feature Recognition (Pre-release) 350

Feature Types 350

Overview of the Feature Recognition Modules 350

Feature Recognition 352

Edit Hole Feature 358

Edit Hole Feature using Radius Constraint= 361

Edit Blend Feature 364

Edit Blend Feature using Radius Constraint= 367

Edit Chamfer Feature 370

Edit Chamfer Feature using Height Constraint= 373

Edit Feature Parameters 376

Show Hole Feature 377

Show Hole Feature using Radius Constraint= 378

Show Blend Feature 379

Show Blend Feature using Radius Constraint= 380

Show Chamfer Feature 381

Show Chamfer Feature using Height Constraint= 382


==

vi

Show Feature Information 383

Delete Hole Feature 384

Delete Hole Feature using Radius Constraint= 385

Delete Blend Feature 386

Delete Blend Feature using Radius Constraint= 387

Delete Chamfer Feature using Height Constraint= 388

Delete Chamfer Feature 389

Delete Any Feature 390

Clear Feature 391

Creating Coordinate Frames 393

Creating Coordinate Frames Using the 3Point Method 393

Creating Coordinate Frames Using the Axis Method 395

Creating Coordinate Frames Using the Euler Method 397

Creating Coordinate Frames Using the Normal Method 401

Creating Coordinate Frames Using the 2 Vector Method 404

Creating Coordinate Frames Using the View Vector Method 405

Creating Planes 407

Creating Planes with the Point-Vector Method 407

Creating Planes with the Vector Normal Method 408

Creating Planes with the Curve Normal Method 410

Creating Planes with the Plane Normal Method 414

Creating Planes with the Interpolate Method 415

Creating Planes with the Least Squares Method 418

Creating Planes with the Offset Method 424

Creating Planes with the Surface Tangent Method 426

Creating Planes with the 3 Points Method 430

Creating Vectors 433

Creating Vectors with the Magnitude Method 433

Creating Vectors with the Interpolate Method 434

Creating Vectors with the Intersect Method 436

Creating Vectors with the Normal Method 438

Creating Vectors with the Product Method 445

Creating Vectors with the 2 Point Method 447

Creating P-Shapes 450

Rectangle 450

Quadrilateral 450

Triangle 451

Disc 452

Cylinder 453

Cone 454

Sphere 455

viiCONTENTS

Paraboloid 456

Five-Sided Box 457

Six-Sided Box 458

Edit P-Shapes 460

5 Delete Actions

Overview of the Geometry Delete Action 462

Deleting Any Geometric Entity 463

Deleting Points, Curves, Surfaces, Solids, Planes or Vectors 464

Deleting Coordinate Frames 466

6 Edit Actions

Overview of the Edit Action Methods 470

Editing Points 472

Equivalencing Points 472

Editing Curves 474

Breaking Curves 474

Blending a Curve 484

Disassembling a Chained Curve 487

Extending Curves 490

Merging Existing Curves 504

Refitting Existing Curves 508

Reversing a Curve 510

Trimming Curves 513

Editing Surfaces 520

Surface Break Options 520

Blending Surfaces 538

Disassembling Trimmed Surfaces 541

Editing Edges from Surfaces 544

Matching Surface Edges 548

Extending Surfaces 553

Refitting Surfaces 568

Reversing Surfaces 570

Sewing Surfaces 572

Subtracting Surfaces 574

Trimming Surfaces to an Edge 575


==

viii

Adding a Fillet to a Surface= 577

Adding a Hole to Surfaces 578

Removing a Hole from Trimmed Surfaces 584

Adding a Vertex to Surfaces 586

Removing a Vertex from Trimmed Surfaces 588

Editing Solids 591

Breaking Solids 591

Blending Solids 607

Disassembling B-rep Solids 610

Refitting Solids 613

Reversing Solids 618

Solid Boolean Operation Add 619

Solid Boolean Operation Subtract 621

Solid Boolean Operation Intersect 623

Creating Solid Edge Blends 625

Imprinting Solid on Solid 629

Solid Shell Operation 631

Editing Features 634

Suppressing a Feature 634

Unsuppressing a Feature 635

Editing Feature Parameters 636

Feature Parameter Definition 637

7 Show Actions

Overview of the Geometry Show Action Methods 640

The Show Action Information Form 641

Showing Points 642

Showing Point Locations 642

Showing Point Distance 644

Showing the Nodes on a Point 658

Showing Curves 660

Showing Curve Attributes 660

Showing Curve Arc 661

Showing Curve Angle 663

Showing Curve Length Range 665

Showing the Nodes on a Curve 667

Showing Surfaces 669

Showing Surface Attributes 669

ixCONTENTS

Showing Surface Area Range 671

Showing the Nodes on a Surface 672

Showing Surface Normals 674

Showing Solids 677

Showing Solid Attributes 677

Showing Coordinate Frames 679

Showing Coordinate Frame Attributes 679

Showing Planes 681

Showing Plane Attributes 681

Showing Plane Angle 682

Showing Plane Distance 684

Showing Vectors 686

Showing Vector Attributes 686

8 Transform Actions

Overview of the Transform Methods 688

Transforming Points, Curves, Surfaces, Solids, Planes and Vectors

691

Translating Points, Curves, Surfaces, Solids, Planes and Vectors 691

Rotating Points, Curves, Surfaces, Solids, Planes and Vectors 705

Scaling Points, Curves, Surfaces, Solids and Vectors 715

Mirroring Points, Curves, Surfaces, Solids, Planes and Vectors 726

Moving Points, Curves, Surfaces, Solids, Planes and Vectors by Coordinate

Frame Reference (MCoord Method) 734

Pivoting Points, Curves, Surfaces, Solids, Planes and Vectors 742

Positioning Points, Curves, Surfaces, Solids, Planes and Vectors 751

Vector Summing (VSum) Points, Curves, Surfaces and Solids 761

Moving and Scaling (MScale) Points, Curves, Surfaces and Solids 770

Transforming Coordinate Frames 779

Translating Coordinate Frames 779

Rotating Coordinate Frames 782

9 Verify Actions

Verify Action 788

Verifying Surface Boundaries 788

Verifying Surfaces for B-reps 790


==

x

Verify=- Surface (Duplicates) 792

10 Associate Actions

Overview of the Associate Action 796

Associating Point Object 797

Associating Curve Object 799

11 Disassociate Actions

Overview of the Disassociate Action Methods 802

Disassociating Points 803

Disassociating Curves 804

Disassociating Surfaces 804

12 The Renumber Action... Renumbering Geometry

Introduction 808

Renumber Forms 809

Renumber Geometry 810

Chapter 1: Introduction to Geometry Modeling


1 Introduction to Geometry

Modeling

� Overview of Capabilities 2

� Concepts and Definitions 4

� Types of Geometry in Patran 20

� Building An Optimal Geometry Model 31

Geometry Modeling - Reference Manual Part 2Overview of Capabilities

2

Overview of Capabilities

A powerful and important feature of Patran is its geometry capabilities. Geometry can be:

• Created.

• Directly accessed from an external CAD part file.

• Imported from an IGES file or a PATRAN 2 Neutral file.

Complete Accuracy of Original Geometry

Patran maintains complete accuracy of the original geometry, regardless of where it came from. The

exact mathematical representation of the geometry (e.g., Arc, Rational B-Spline, B-rep, Parametric

Cubic, etc.) is consistently maintained throughout the modeling process, without any approximations or

conversions.

This means different versions of the geometry model are avoided. Only one copy of the geometry design

needs to be maintained by the engineer, whether the geometry is in a separate CAD part file or IGES file

or the geometry is part of the Patran database.

Below are highlights of the geometry capabilities:

Direct Application of Loads/BCs and Element Properties to Geometry

All loads, boundary conditions (BC) and element property assignments can be applied directly to the

geometry. When the geometry is meshed with a set of nodes and elements, Patran will automatically

assign the loads/BC or element property to the appropriate nodes or elements.

Although you can apply the loads/BCs or element properties directly to the finite element mesh, the

advantage of applying them to the geometry is if you remesh the geometry, they remain associated with

the model. Once a new mesh is created, the loads/BC and element properties are automatically

reassigned.

For more information, see Introduction to Functional Assignment Tasks (Ch. 1) in the Patran Reference

Manual.

Direct Geometry Access

Direct Geometry Access (DGA) is the capability to directly access (or read) geometry information from

an external CAD user file, without the use of an intermediate translator. Currently, DGA supports the

following CAD systems:

• EDS/Unigraphics

• Pro/ENGINEER by Parametric Technology

• CATIA by Dassault Systemes

With DGA, the CAD geometry and its topology that are contained in the CAD user file can be accessed.

Once the geometry is accessed, you can build upon or modify the accessed geometry in Patran, mesh the

geometry, and assign the loads/BC and the element properties directly to the geometry.

3Chapter 1: Introduction to Geometry ModelingOverview of Capabilities

For more detailed information on DGA, see Direct Geometry Access of CAD Geometry, 47.

Import and Export of Geometry

There are three file formats available to import or export geometry:

• IGES

• PATRAN 2 Neutral File

• Express Neutral File

In using any of the file formats, Patran maintains the original mathematical form of the geometry. (That

is, the geometry is not approximated into the parametric cubic form.) This means the accuracy of the

geometry in all three files is maintained.

For more information on the import and export capabilities for IGES, PATRAN 2 Neutral File, and the

Express Neutral File, see Accessing, Importing & Exporting Geometry.

Patran Native Geometry

You can also create geometry in Patran (“native” geometry). A large number of methods are available to

create, translate, and edit geometry, as well as methods to verify, delete and show information.

Patran’s native geometry consists of:

• Points

• Parametric curves

• Bi-parametric surfaces

• Tri-parametric solids

• Boundary represented (B-rep) solids

All native geometry is fully parameterized both on the outer boundaries and within the interior (except

for B-rep solids which are parameterized only on the outer surfaces).

Fully parameterized geometry means that you can apply varying loads or element properties directly to

the geometric entity. Patran evaluates the variation at all exterior and interior locations on the geometric

entity.

Geometry Modeling - Reference Manual Part 2Concepts and Definitions

4

Concepts and Definitions

There are many functions in Patran that rely on the mathematical representation of the geometry. These

functions are:

• Applying a pressure load to a curve, surface or solid.

• Creating a field function in parametric space.

• Meshing a curve, surface or solid.

• Referencing a vertex, edge or face of a curve, surface or solid.

For every curve, surface or solid in a user database, information is stored on its Parameterization,

Topology and Connectivity which is used in various Patran functions.

The concepts of parameterization, connectivity and topology are easy to understand and they are

important to know when building a geometry and an analysis model.

The following sections will describe each of these concepts and how you can build an optimal geometry

model for analysis.

Parameterization

All Patran geometry are labeled one of the following:

• Point (0-Dimensions)

• Curve (1-Dimension)

• Surface (2-Dimensions)

• Solid (3-Dimensions)

Depending on the order of the entity - whether it is a one-dimensional curve, a two-dimensional surface,

or a three-dimensional solid - there is one, two or three parameters labeled , , that are associated

with the entity. This concept is called “parameterization”.

Parameterization means the X,Y,Z coordinates of a curve, surface or solid are represented as functions

of variables or parameters. Depending on the dimension of the entity, the X,Y,Z locations are functions

of the parameters , , and .

An analogy to the parameterization of geometry is describing an , location as a function of time, t.

If and , as changes, and will define a path. Parameterization of geometry

does the same thing - as the parameters , , and change, it defines various points on the curve,

surface and solid.

The following describes how a point, curve, surface and solid are parameterized in Patran.

Point

A Point in Patran is a point coordinate location in three-dimensional global XYZ space.

ξ1

ξ2

ξ3

ξ1

ξ2

ξ3

X Y t

X X t( )Z Y Y t( )Z t X Y

ξ1

ξ2

ξ3

5Chapter 1: Introduction to Geometry ModelingConcepts and Definitions

Since a point has zero-dimensions, it has no associated parameters, therefore, it is not parameterized.

Figure 1-1 Point in Patran

Curve

A Curve in Patran is a one-dimensional point set in three-dimensional global XYZ space. A curve can

also be described as a particle moving along a defined path in space.

Another way of defining a curve is, a curve is a mapping function, , from one-dimensional

parametric space into three-dimensional global XYZ space, as shown in Figure 1-3.

A curve has one parametric variable, , which is used to describe the location of any given point, ,

along a curve, as shown in Figure 1-2.

Figure 1-2 Curve in Patran

The parameter, , has a range of , where at , is at endpoint and at , is at

endpoint .

Φ ξ1

( )

ξ1

P

ξ1

0 ξ1

1≤ ≤ ξ1

0Z P V1 ξ1

1Z P

V2


6

A straight curve can be defined as:

(1-1)

Figure 1-3 Mapping Function Phi for a Curve

(1-1) of our straight curve can be represented as:

(1-2)

The derivative of in (1-2), would give us (1-3) which is the tangent of the straight curve.

(1-3)

Because the curve is straight, is a constant value. The tangent, , also defines a vector for

the curve, which is the positive direction of .

For any given curve, the tangent and positive direction of at any point along the curve can be found.

(The vector, , usually will not have a length of one.)

Surface

A surface in Patran is a two-dimensional point set in three-dimensional global XYZ space.

A surface has two parameters, and , where at any given point, , on the surface, can be located

by and , as shown in Figure 1-4.

P 1.0 ξ1

Ó( )V1 ξ1V2HZ

Φξ1

1.0 ξ1

Ó( )V1 ξ1V2HZ

Φ ξ1

( )

∂Φ ∂ξ1

⁄ V2 V1ÓZ

∂Φ ∂ξ1

⁄ ∂Φ ∂ξ1

⁄

ξ1

ξ1

∂Φ ∂ξ1

⁄

ξ1

ξ2

P P

ξ1

ξ2


Figure 1-4 Surface in Patran

A surface generally has three or four edges. Trimmed surfaces can have more than four edges. For more

information, see Trimmed Surfaces, 20.

Similar to a curve, and for a surface have ranges of and . Thus, at ,

, is at and at , , is at .

A surface is represented by a mapping function, , which maps the parametric space into the

global XYZ space, as shown in Figure 1-5.

ξ1

ξ2

0 ξ1

1≤ ≤ 0 ξ2

1≤ ≤ ξ1

0Z

ξ2

0Z P V1 ξ1

1Z ξ2

1Z P V3

Φ ξ1ξI2

( )


8

import a B-rep See B-rep Solid,

Figure 1-5 Mapping Function Phi for a Surface

The first order derivatives of results in two partial derivatives, and :

(1-4)

where is the tangent vector in the direction and is the tangent vector in the direction.

At any point for a given surface, and which define the tangents and the positive and

directions can be determined.

Usually and are not orthonormal, which means they do not have a length of one and they are not

perpendicular to each other.

Solid

A solid in Patran is a three-dimensional point set in three-dimensional global XYZ space.

A solid has three parameters, , , and , where at any given point, , within the solid, can be

located by , , and , as shown in Figure 1-6.

Φ ξ1ξI2

( ) ∂Φ ∂ξ1

⁄ ∂Φ ∂ξ2

⁄

∂Φ ∂ξ1

⁄ Tξ1 and ∂Φ ∂ξ2

⁄ Tξ2ZZ

Tξ1 ξ1

Tξ2 ξ2

Tξ1 Tξ2 ξ1

ξ2

Tξ1 Tξ2

ξ1

ξ2

ξ3

P P

ξ1

ξ2

ξ3

Note: Note: The above definition applies to tri-parametric solids only. Patran can also create orsolid, which is parameterized on the outer surface only, and not within the interior.for more information.


Figure 1-6 Solid in Patran

A solid generally has five or six sides or faces. (A B-rep solid can have more than six faces.)

The parameters , and have ranges of , , and . At (0,0,0) is at

and at (1,1,1), is at .

A solid can be represented by a mapping function, , which maps the parametric space into the

global XYZ space, as shown in Figure 1-7.

ξ1

ξ2

ξ3

0 ξ1

1≤ ≤ 0 ξ2

1≤ ≤ 0 ξ3

1≤ ≤ P V1

P V7

Φ ξ1ξI2ξ3

I( )


10

Figure 1-7 Mapping Function Phi for a Solid

If we take the first order derivatives of , we get three partial derivatives, , and

, shown in (1-5):

(1-5)

Where is the tangent vector in the direction, is the tangent vector in the direction, and

is the tangent vector in the direction.

At any point within a given solid, , and , which define the tangents and positive , and

directions can be determined.

Topology

Topology identifies the kinds of items used to define adjacency relationships between geometric entities.

Every curve, surface and solid in Patran has a defined set of topologic entities. You can reference these

entities when you build the geometry or analysis model. Examples of this include:

• Creating a surface between edges of two surfaces.

Φ ξ1ξI2ξ3

I( ) ∂Φ ∂ξ1

⁄ ∂Φ ∂ξ2

⁄

∂Φ ∂ξ3

⁄

∂Φ ∂ξ1

⁄ Tξ1 , ∂Φ ∂ξ2

⁄ Tξ2 , ∂Φ ∂ξ3

⁄ Tξ3ZZZ

Tξ1 ξ1

Tξ2 ξ2

Tξ3

ξ3

Tξ1 Tξ2 Tξ3 ξ1

ξ2

ξ3


• Meshing an edge or a face of a solid.

• Referencing a vertex of a curve, surface or solid to apply a loads/BC.

Topology is invariant through a one-to-one bicontinuous mapping transformation. This means you can

have two curves, surfaces or solids that have different parameterizations, but topologically, they can be

identical.

To illustrate this concept, Figure 1-8 shows three groups of surfaces A-D. Geometrically, they are

different, but topologically they are the same.

Figure 1-8 Topologically Equivalent Surfaces

Topologic Entities: Vertex, Edge, Face, Body

The types of topologic entities found in Patran are the following:


12

Vertex, Edge and Face ID Assignments in Patran

The connectivity for a curve, surface and solid determines the order in which the internal vertex, edge

and face IDs will be assigned. The location of a geometric entity’s parametric axes defines the point

where assignment of the IDs for the entity’s vertices, edges and faces will begin.

Figure 1-9 and Figure 1-10 show a four sided surface and a six sided solid with the internal vertex, edge

and face IDs displayed. If the connectivity changes, then the IDs of the vertices, edges and faces will also

change.

Figure 1-9 Vertex & Edge Numbering for a Surface

Vertex Defines the topologic endpoint of a curve, or a corner of a surface or a solid. A vertex is

separate from a geometric point, although a point can exist on a vertex.

Edge Defines the topologic curve on a surface or a solid. An edge is separate from a geometric

curve, although a curve can exist on an edge.

Face Defines the topologic surface of a solid. A face is separate from a geometric surface,

although a surface can exist on a face.

Body A group of surfaces that forms a closed volume. A body is usually referenced as a B-rep

solid or a Volume solid, where only its exterior surfaces are parameterized. See Solids,

24 for more information.

Important:Generally, when modeling in Patran, you do not need to know the topologic entities’

internal IDs. When you cursor select a topologic entity, such as an edge of a surface, the ID

will be displayed in the appropriate listbox on the form.


Figure 1-10 Face Numbering for a Solid

For example, in Figure 1-9, the edge, ED3, of Surface 11 would be displayed as:

Surface 11.3

The vertex, V4, in Figure 1-9 would be displayed as:

Surface 11.3.1

V4 has a vertex ID of 1 that belongs to edge 3 on surface 11.

The face, F1, of Solid 100 in Figure 1-9 would be displayed as:

Solid 100.1

The edge, ED10, in Figure 1-10 would be displayed as:

Solid 100.1.3

ED10 has an edge ID of 3 that belongs to face 1 on solid 100.

The vertex, V6, in Figure 1-10 would be displayed as:

Solid 100.1.2.2

V6 has a vertex ID of 2 that belongs to edge 2 on face 1 on solid 100.

Topological Congruency and Meshing

When meshing adjacent surfaces or solids, Patran requires the geometry be topologically congruent so

that coincident nodes will be created along the common boundaries.


14

Figure 1-11 shows an example where surfaces 1 through 3 are topologically incongruent and surfaces 2

through 5 are topologically congruent. The outer vertices are shared for surfaces 1 through 3, but the

inside edges are not. Surfaces 2 through 5 all have common edges, as well as common vertices.

There are several ways to correct surfaces 1 through 3 to make them congruent. See Building a Congruent

Model for more information.

Figure 1-11 Topologically Incongruent and Congruent Surfaces

For a group of surfaces or solids to be congruent, the adjacent surfaces or solids must share common

edges, as well as common vertices.

(MSC.Software Corporation’s Patran software product required adjacent surfaces or solids to share only

the common vertices to be considered topologically congruent for meshing.)

Gaps Between Adjacent Surfaces

Another type of topological incongruence is shown in Figure 1-12. It shows a gap between two pairs of

surfaces that is greater than the Global Model Tolerance. This means when you mesh the surface pairs,

coincident nodes will not be created along both sides of the gap.


Figure 1-12 Topologically Incongruent Surfaces with a Gap

MSC recommends two methods for closing surface gaps:

• Use the Create/Surface/Match form. See Matching Adjacent Surfaces.

• Use the Edit/Surface/Edge Match form. See Matching Surface Edges.

For more information on meshing, see Introduction to Functional Assignment Tasks (Ch. 1) in the Patran

Reference Manual.

Non-manifold Topology

Non-manifold topology can be simply defined as a geometry that is non-manufacturable. However, in

analysis, non-manifold topology is sometimes either necessary or desirable. Figure 1-13 shows a surface

model with a non-manifold edge.


16

Figure 1-13 Non-manifold Topology at an Edge

This case may be perfectly fine. A non-manifold edge has more than two surfaces or solid faces

connected to it. Therefore, two solids which share a common face also give non-manifold geometry (both

the common face and its edges are non-manifold).

In general, non-manifold topology is acceptable in Patran. The exception is in the creation of a B-rep

solid where a non-manifold edge is not allowed. The Verifying Surface Boundaries option detects non-

manifold edges as well as free edges.

Connectivity

In Figure 1-2, Figure 1-4, and Figure 1-6 in Parameterization, the axes for the parameters, , , and ,

have a unique orientation and location on the curve, surface and solid.

Depending on the orientation and location of the , , and axes, this defines a unique connectivity

for the curve, surface or solid.

For example, although the following two curves are identical, the connectivity is different for each curve

(note that the vertex IDs are reversed):

ξ1

ξ2

ξ3

ξ1

ξ2

ξ3


Figure 1-14 Connectivity Possibilities for a Curve

For a four sided surface, there are a total of eight possible connectivity definitions. Two possible

connectivities are shown in Figure 1-15. (Again, notice that the vertex and edge IDs are different for each

surface.)

Figure 1-15 Two Possible Connectivities for a Surface

For a tri-parametric solid with six faces, there are a total of 24 possible connectivity definitions in Patran

- three orientations at each of the eight vertices. Two possible connectivities are shown in Figure 1-16.

Figure 1-16 Two Possible Connectivities for a Solid


18

Plotting the Parametric Axes

Patran can plot the location and orientation of the parametric axes for the geometric entities by turning

on the Parametric Direction toggle on the Geometric Properties form, under the Display/Display

Properties/Geometric menu. See Preferences>Geometry (p. 459) in the Patran Reference Manual for

more information.

Modifying the Connectivity

For most geometric entities, you can modify the connectivity by altering the orientation and/or location

of the parametric axes by using the Geometry application’s Edit action’s Reverse method. See Overview

of the Edit Action Methods.

For solids, you can also control the location of the parametric origin under the Preferences/Geometry

menu and choose either the Patran Convention button or the PATRAN 2.5 Convention button for the

Solid Origin Location.

Effects of Parameterization, Connectivity and Topology in Patran

The geometry’s parameterization and connectivity affect the geometry and finite element analysis model

in the following ways:

Defines Order of Internal Topologic IDs

The parameterization and connectivity for a curve, surface or solid define the order of the internal IDs of

their topologic entities. Patran stores these IDs internally and displays them when you cursor select a

vertex, edge or face. See Vertex, Edge and Face ID Assignments in Patran for more information.

Defines Positive Surface Normals

Using right hand rule by crossing a surface’s direction with its direction, it defines the surface’s

positive normal direction ( direction). This affects many areas of geometry and finite element creation,

including creating B-rep solids. See Building An Optimal Geometry Model for more information.

Defines Positive Pressure Load Directions

The parameterization and connectivity of a curve, surface or solid define the positive direction for a

pressure load, and it defines the surface’s top and bottom locations for an element variable pressure load.

See Create Structural LBCs Sets (p. 27) in the Patran Reference Manual for more information.

Helps Define Parametric Field Functions

If you reference a field function that was defined in parametric space, when creating a varying loads/BC

or a varying element or material property, the loads/BC values or the property values will depend on the

geometry’s parameterization and the orientation of the parametric axes. See Fields Forms (p. 210) in the

Patran Reference Manual for more information.

ξ1

ξ2

ξ3


Defines Node and Element ID Order For IsoMesh

The Patran mapped mesher, IsoMesh, will use the geometric entity’s parameterization and connectivity

to define the order of the node and element IDs and the element connectivity. (The parameterization and

connectivity will not be used if the mesh will have a transition or change in the number of elements within

the surface or solid.) See IsoMesh (p. 13) in the Reference Manual - Part III for more information.

Global Model Tolerance & Geometry

Patran uses the Global Model Tolerance when it imports or accesses geometry, when it creates geometry,

or when it modifies existing geometry.

The Global Model Tolerance is found under the Preferences/Global menu. The default value is 0.005.

When creating geometry, if two points are within a distance of the Global Model Tolerance, then Patran

will only create the first point and not the second.

This rule also applies to curves, surfaces and solids. If the points that describe two curves, surfaces or

solids are within a distance of the Global Model Tolerance, then only the first curve, surface or solid will

be created, and not the second.

For more information on the Global Model Tolerance, see (p. 68) in the Patran Reference Manual.

Important:For models with dimensions which vary significantly from 10 units, MSC recommends you

set the Global Model Tolerance to .05% of the maximum model dimension.

Geometry Modeling - Reference Manual Part 2Types of Geometry in Patran

20

Types of Geometry in Patran

Generally, there are four types of geometry objects in Patran:1

• Point (default color is cyan)

• Parametric Curve (default color is yellow)

• Bi-Parametric Surface (default color is green)

• Tri-Parametric Solid (default color is dark blue)

Patran also can access, import, and create Trimmed Surfaces, B-rep Solids and Volume Solids. See

Trimmed Surfaces and Solids for more information.

You also can create parametric cubic curves, surfaces and solids, which are recognized by the

PATRAN 2 neutral file. See Parametric Cubic Geometry for more information.

For more information on the types of geometry that can be created, see Matrix of Geometry Types

Created.

Trimmed Surfaces

Trimmed surfaces are a special class of bi-parametric surfaces. Trimmed surfaces can be accessed from

an external CAD user file; they can be imported from an IGES or Express Neutral file; and they can be

created in Patran.

Unlike other types of bi-parametric surfaces, trimmed surfaces can have more than four edges, and they

can have one or more interior holes or cutouts.

Also, trimmed surfaces have an associated parent surface that is not displayed. A trimmed surface is

defined by identifying the closed active and inactive regions of the parent surface. This parent surface

defines the parameterization and curvature of the trimmed surface.

You can create three types of trimmed surfaces in Patran:2

• General Trimmed Surface (default color is magenta)

• Simply Trimmed Surface (default color is green)

• Composite Trimmed Surface (default is magenta)

• Ordinary Composite Trimmed Surface (default color is green)

(Green is the default color for both a simply trimmed surface and a general, bi-parametric surface.)

1The default colors are used if the Display Method is set to Entity Type, instead of Group, on the

Graphics Preferences form under the Preferences/Graphics menu.



21Chapter 1: Introduction to Geometry ModelingTypes of Geometry in Patran

General Trimmed Surface

A general trimmed surface can have any number of outer edges and any number of inner edges which

describe holes or cutouts. These outer and inner edges are defined by a closed loop of chained curves.

(Chained curves can be created with the Create/Curve/Chain form. See Creating Chained Curves.) An

example is shown in Figure 1-17.

All general trimmed surfaces, whether they are accessed, imported or created, have a default color of

magenta.1

Figure 1-17 General Trimmed Surface

Important:Simply trimmed surfaces and ordinary composite trimmed surfaces can be meshed with

IsoMesh or Paver. General trimmed surfaces and composite trimmed surfaces can only be

meshed with Paver. See Meshing Surfaces with IsoMesh or Paver (p. 13) in the Reference

Manual - Part III for more information. Also note that some geometric operations are not

currently possible with a general trimmed surface, e.g., a general trimmed surface can not

be used to create a triparametric solid.




22

Simply Trimmed Surface

A simply trimmed surface can only have four outer edges. It cannot have any inner edges, or holes or

cutouts. A simply trimmed surface reparametrizes the bounded region of the parent and is called an

overparametrization. An example is shown in Figure 1-18. (A simply trimmed surface can have three

sides, with one of the four edges degenerating to a zero length edge.)

Like a general trimmed surface, a simply trimmed surface’s outer edges are defined by a closed loop of

chained curves. See Creating Chained Curves.

All simply trimmed surfaces, whether they are accessed, imported or created, have a default color of

green. 1

Figure 1-18 Simply Trimmed Surface

Sometimes a three of four sided region which define a trimmed surface will be created as a general

trimmed surface instead. This occurs when the overparametrization distorts the bounded region of the

parent to such an extent that it would be difficult to mesh and use for analysis.

Composite Trimmed Surface

The composite trimmed surface is a kind of supervisor surface that allows a collection of surfaces to be

considered as one surface defined within a specific boundary. This surface can also have holes in it.

Evaluations on the composite trimmed surface is similar to evaluations on the Patran trim surface




(General Trimmed Surface). The big difference is that it is three to five times slower than ordinary

surfaces.

The composite trimmed surface should be considered a tool. Once the surface is built, it is a single entity,

yet processes on multiple surfaces, relieving the applications of the task of determining where and when

to move from one surface to another.

APPLICATION: The composite trimmed surface supervisor is a bounded PLANAR trim surface. It

acquires its name from the type of service it performs. Let us, for a moment, consider the composite

trimmed surface to be a cloud in the sky. The sun, being the light source behind the cloud, creating a

shadow on planet earth only in the area blocked by the cloud. The same is true with the composite

trimmed surface, except a view vector is given to determine the light direction. “Under Surfaces” replace

planet earth. The valid region on the “Under Surfaces” is defined by where the outline of the composite

trimmed surface appears.

STEPS_BUILDING: There are three basic steps in building a composite trimmed surface.

RULES:

1. The composite trimmed surface domain must not encompass any dead space. If any portion has

a vacancy (no “Under Surface” under it), unpredictable results will occur.

2. Processing along the view vector must yield a single intersection solution at any position on the

underlying surfaces within the composite trimmed surface’s domain.

Step 1 Creating the outer perimeter curve. In most cases this is a Patran curve chain entity.

Step 2 Selecting an acceptable view direction for the view vector and planar Composite

trimmed surface entity. The view vector is the most important aspect of building a

composite trimmed surface. The resulting view vector must yield only one

intersection solution at any position on the “Under Surfaces”. The user must select

the proper view for the location of the composite trimmed surface with some

forethought and eliminate the possibility of any of the underlying surfaces

wrapping around in back of one another. In some cases this may not be possible!

The user must then create more than one composite trimmed surface.

Additionally, since the composite trimmed surface supervisor is PLANAR, it

cannot encompass more than a 180 degree field of view. An example of this would

be a cylindrically shaped group of surfaces. It would probably take three properly

placed composite trimmed surface to represent it; one for every 120 degrees of

rotation.

Step 3 Determines which currently displayed surfaces will be become part of the

composite trimmed surface domain (“Under Surfaces”). The user may individually

select the correct underlying surfaces or, if wanting to select all visible surfaces,

the user must place into “ERASE” all surfaces which might cause multiple

intersections and then select the remaining visible surfaces.


24

Ordinary Composite Trimmed Surface

The only difference between an Ordinary Composite Trimmed Surface and the Composite Trimmed

Surface is that this type will have only four edges comprising the outer loop and no inner loops.

Solids

There are three types of solids that can be accessed or imported, or created in Patran:1

• Tri-Parametric Solid (default color is dark blue)

• B-rep Solid (default color is white)

• Volume Solid (default color is pink or light red)

on (p. 2) lists the types of solids created with each Geometry Application method.

Tri-Parametric Solid

All solids in Patran, except for B-rep solids and volume solids, are tri-parametric solids. Tri-parametric

solids are parameterized on the surface, as well as inside the solid. Tri-parametric solids can only have

four to six faces with no interior voids or holes.

Tri-parametric solids can be meshed with IsoMesh or TetMesh.

B-rep Solid

A B-rep solid is formed from a group of topologically congruent surfaces that define a completely closed

volume. Only its outer surfaces or faces are parameterized and not the interior. An example is shown in

Figure 1-19.

The group of surfaces that define the B-rep solid are its shell. A B-rep shell defines the exterior of the

solid, as well as any interior voids or holes. Shells can be composed of bi-parametric surfaces and/or

trimmed surfaces.

B-rep solids can be created with the Create/Solid/B-rep form. See Creating a Boundary Representation

(B-rep) Solid on using the form.



Note: IsoMesh will create hexagonal elements if the solid has five or six faces, but some wedge

elements will be created for the five faced solid. IsoMesh will create a tetrahedron mesh for

a four faced solid. See Meshing Solids (p. 14) in the Reference Manual - Part III.


Figure 1-19 B-rep Solid in Patran

B-rep solids are meshed with TetMesh. See Meshing Solids (p. 14) in the Reference Manual - Part III for

more information.

Parametric Cubic Geometry

Parametric cubic geometry is a special class of parameterized geometry. Parametric cubic geometry is

supported in Patran by the PATRAN 2 neutral file and the IGES file for import and export.

You have the option to create parametric cubic curves, bi-parametric cubic surfaces and tri-parametric

cubic solids, by pressing the PATRAN 2 Convention button found on most Geometry application forms.

Parametric cubic geometry can also be created in Patran, which are referred to as “grids”, “lines”,

“patches” and “hyperpatches.”

Parametric cubic geometry is defined by a parametric cubic equation. For example, a parametric cubic

curve is represented by the following cubic equation:

(1-6)

where represents the general coordinate of the global coordinates X,Y, and Z; , , , and

are arbitrary constants; and is a parameter in the range of .

For more information on parametric cubic geometry, see Patran Reference Manual.

Note: Unless you intend to export the geometry using the PATRAN 2 neutral file, in most

situations, you do not need to press the PATRAN 2 Convention button to create parametric

cubic geometry.

Z ξ1

( ) S1ξ1

3Z S

2ξ1

2S3ξ1

S4

H H H

Z ξ1

( ) S1

S2

S3

S4

ξ1

0 ξ1

1≤ ≤


26

Limitations on Parametric Cubic Geometry

There are some limitations on parametric cubic geometry.

Limits on Types of Curvature

There are limits to the types of curvature or shapes that are allowed for a parametric cubic curve, surface

or solid (see Figure 1-20).

(1-7) and (1-8) below represent the first and second derivatives of (1-6):

(1-7)

(1-8)

(1-7) shows that a parametric cubic curve can only have two points with zero slope and (1-8) shows that

it can only have one point of inflection, as shown in Figure 1-20.

Figure 1-20 Limitations of the Parametric Cubic Curvature

Limits on Accuracy of Subtended Arcs

When you subtend an arc using a parametric cubic curve, surface or solid, the difference between the true

arc radius and the arc radius calculated by the parametric cubic equation will increase. That is, as the

angle of a subtended arc for a parametric cubic entity increases, the accuracy of the entity from the true

representation of the arc decreases.

Figure 1-21 shows that as the subtended angle of a parametric cubic entity increases, the percent error

also increases substantially beyond 75 degrees.

When creating arcs with parametric cubic geometry, MSC recommends using Figure 1-21 to determine

the maximum arc length and its percent error that is acceptable to you.

For example, if you create an arc length of 90 degrees, it will have an error of 0.0275% from the true arc

length.

Z ′ ξ1

( ) 3S1ξ1

2Z 2S

2ξ1

S3

H H

Z″ ξ1

( ) 6S1ξ1

Z 2S2

H


For most geometry models, MSC recommends arc lengths represented by parametric cubic geometry

should be 90 degrees or less. For a more accurate model, the parametric cubic arc lengths should be 30

degrees or less.

Figure 1-21 Maximum Percent Error for Parametric Cubic Arc

Matrix of Geometry Types Created

All Geometry Application forms use the following Object menu terms:

• Point

• Curve

• Surface

• Solid

• Plane

• Vector

• Coordinate Frame

Patran will create a specific geometric type of the parametric curve, bi-parametric surface and tri-

parametric solid based on the method used for the Create action or Edit action.

Table 1-1, and list the types of geometry created for each Create or Edit action method. The tables also

list if each method can create parametric cubic curves, surfaces or solids by pressing the PATRAN 2


28

Convention button on the application form. (Parametric cubic geometry is recognized by the PATRAN 2

neutral file for export.)

For more information on each Create or Edit action method, see Overview of Geometry Create Action

and/or Overview of the Edit Action Methods.

Table 1-1 Types of Curves Created in Patran

Create or Edit Method Type of Curve

PATRAN 2 Convention?

(Parametric Cubic)

XYZ Parametric Cubic Not Applicable

Arc3Point Arc Yes

2D Arc2Point Arc Yes

2D Arc3Point Arc Yes

2D Circle Circle Yes

Conic Parametric Cubic N/A

Extract Curve On Surface Yes

Fillet Parametric Cubic N/A

Fit Parametric Cubic N/A

Intersect PieceWise Cubic Polynomial Yes

Involute Parametric Cubic N/A

Normal Parametric Cubic N/A

2D Normal Parametric Cubic N/A

2D ArcAngles Arc Yes

Point Parametric Cubic N/A

Project Curve On Surface Yes

PWL Parametric Cubic N/A

Revolve Arc Yes

Spline, Loft Spline option PieceWise Cubic Polynomial Yes

Spline, B-Spline option PieceWise Rational Polynomial Yes

Spline, B-Spline option NURB* Yes

TanCurve Parametric Cubic N/A

TanPoint Parametric Cubic N/A

Chain Composite Curve No

Manifold Curve On Surface Yes


*NURB splines are created if the NURBS Accelerator toggle is pressed OFF (default is ON)

on the Geometry Preferences form, found under the Preferences/Geometry menu. This is true whether

you create the spline in Patran or if you import the spline from an IGES file. See

Preferences>Geometry (p. 459) in the Patran Reference Manual for more information. If the NURBS

Accelerator is ON, PieceWise Rational Polynomial splines will be created instead.

Table 1-2 Types of Surfaces Created in Patran

Create or Edit Method Type of Surface


(Parametric Cubic)

XYZ Parametric Bi-Cubic Not Applicable

Curve Curve Interpolating Surface Yes

Decompose Trimmed Surface Yes

Edge Generalized Coons Surface Yes

Extract Surface On Solid Yes

Extrude Extruded Surface Yes

Fillet Parametric Bi-Cubic N/A

Glide Parametric Bi-Cubic N/A

Match Parametric Bi-Cubic N/A

Normal Sweep Normal Surface N/A

Revolve Surface of Revolution Yes

bordered Ruled Surface No

Vertex Curve Interpolating Surface Yes

Trimmed (Surface Option) Trimmed Surface No

Trimmed (Planar Option) Trimmed Surface No

Trimmed (Composite Option) Composite Trimmed Surface No

Table 1-3 Types of Solids Created in Patran

Create or Edit Method Type of Solid


(Parametric Cubic)

XYZ Parametric Tri-Cubic Not Applicable

Extrude Extruded Solid Yes

Face Solid 5Face, Solid 6Face Yes

Glide Glide Solid Yes

Normal Sweep Normal Solid Yes


30

Revolve Solid of Revolution Yes

Surface Surface Interpolating Solid Yes

Vertex Parametric Tri-Cubic N/A

B-rep Ordinary Body No

Decompose Tri-Parametric Yes

Table 1-3 Types of Solids Created in Patran

Create or Edit Method Type of Solid


(Parametric Cubic)

31Chapter 1: Introduction to Geometry ModelingBuilding An Optimal Geometry Model

Building An Optimal Geometry Model

A well defined geometry model simplifies the building of the optimal finite element analysis model. A

poorly defined geometry model complicates, or in some situations, makes it impossible to build or

complete the analysis model.

In computer aided engineering (CAE) analysis, most geometry models do not consist of neatly trimmed,

planar surfaces or solids. In some situations, you may need to modify the geometry to build a congruent

model, create a set of degenerate surfaces or solids, or decompose a trimmed surface or B-rep solid.

The following sections will explain how to:

• Build a congruent model.

• Verify and align surface normals.

• Build trimmed surfaces.

• Decompose trimmed surfaces into three- or four-sided surfaces.

• Build a B-rep solid.

• Build degenerate surfaces or solids.

Building a Congruent Model

Patran requires adjacent surfaces or solids be topologically congruent so that the nodes will be coincident

at the common boundaries. See Topological Congruency and Meshing for more information.

For example, Figure 1-22 shows surfaces 1, 2 and 3 which are incongruent. When meshing with Isomesh

or Paver, Patran cannot guarantee the nodes will coincide at the edges shared by surfaces 1, 2 and 3.

Figure 1-22 Incongruent Set of Surfaces

To make the surfaces in Figure 1-22 congruent, you can:

Geometry Modeling - Reference Manual Part 2Building An Optimal Geometry Model

32

• Use the Edit/Surface/Edge Match form with the Surface-Point option. See Matching Surface

Edges on using the form.

• Or, break surface 1 with the Edit/Surface/Break form. See Surface Break Options on using the

form.

The following describes the method of using the Edit/Surface/Break form.

To make surfaces 1 through 3 congruent, we will break surface 1 into surfaces 4 and 5, as shown in

Figure 1-23:

Figure 1-23 Congruent Set of Surfaces

The entries for the Edit/Surface/Break form are shown below:


Since Auto Execute is ON, we do not need to press the Apply button to execute the form.

Figure 1-24 Cursor Locations for Surface Break

Building Optimal Surfaces

Building optimal surfaces will save time and it will result in a better idealized finite element analysis

model of the design or mechanical part.

Optimal surfaces consist of a good overall shape with no sharp corners, and whose normal is aligned in

the same direction with the other surfaces in the model.

u Geometry

Action: Edit

Object: Surface

Method: Break

Option: Point

Delete Original Surfaces

Pressing this button will delete surface 1, after

the break.

Surface List: Surface 1 Cursor select or enter the ID for surface 1.

Break Point List Point 10 Cursor select or enter the ID for point 10, as

shown in Figure 1-24.


34

Avoiding Sharp Corners

In general, MSC.Software Corporation (MSC) recommends that you avoid sharp inside corners when

creating surfaces. That is, you should generally try to keep the inside corners of the surfaces to 45 degrees

or more.

The reason is that when you mesh surfaces with quadrilateral elements, the shapes of the elements are

determined by the overall shape of the surface, see Figure 1-25. The more skewed the quadrilateral

elements are, the less reasonable your analysis results might be.

For further recommendations, please consult the vendor documentation for your finite element analysis

code.

Figure 1-25 Surfaces With and Without Sharp Corners

Verifying and Aligning Surface Normals Using Edit/Surface/Reverse

Patran can determine the positive normal direction for each surface by using right hand rule and crossing

the parametric and axes of a surface. Depending on the surface’s connectivity, each surface could

have different normal directions, as shown in Figure 1-26.

Note: You can use the surface display lines to predict what the surface element shapes will look

like before meshing. You can increase or decrease the number of display lines under the

menus Display/Display Properties/Geometric. See Display>Geometry (p. 377) in the

Patran Reference Manual.

ξ1

ξ2


Figure 1-26 Opposing Normals for Two Surfaces

The normal direction of a surface affects finite element applications, such defining the positive pressure

load direction, the top and bottom surface locations for a variable pressure load, and the element

connectivity.

Use the Edit/Surface/Reverse form to display the surface normal vectors, and to reverse or align the

normals for a group of surfaces. See Reversing Surfaces on using the form.

Example of Verifying and Aligning Surface Normals

For example, Figure 1-27 shows a group of eight surfaces that we want to display the normal vectors, and

if necessary, reverse or align the normals. To display the surface normals without reversing, do the

following:

Important:In general, you should try to maintain the same normal direction for all surfaces in a model.


36

Figure 1-27 Group of Surfaces to Verify Normals

You should see red arrows drawn on each surface which represent the surface normal vectors, as shown

in Figure 1-28.

u Geometry

Action: Edit

Object: Surface

Method: Reverse

Surface List Surface 1:8 Make sure you turn Auto Execute OFF before

cursor selecting surfaces 1-8.

And do not press Apply. Apply will reverse

the normals.

Draw Normal Vectors


Figure 1-28 Surface Normal Vectors

Align the normals by reversing the normals for surfaces 1 through 4:

Figure 1-29 shows the updated normal directions which are now aligned.

Figure 1-29 Aligned Surface Normal Vectors

Surface List Surface 1:4

-Apply-

Draw Normal Vectors This will plot the updadirections.


38

Decomposing Trimmed Surfaces

Trimmed surfaces are preferred for modeling a complex part with many sides. However, there may be

areas in your model where you may want to decompose, or break, a trimmed surface into a series of three

or four sided surfaces.

One reason is that you want to mesh the surface area with IsoMesh instead of Paver. (IsoMesh can only

mesh surfaces that have three or four edges.) Another reason is that you want to create tri-parametric

solids from the decomposed three or four sided surfaces and mesh with IsoMesh.

To decompose a trimmed surface, use the Geometry application’s Create/Surface/Decompose form. See

Decomposing Trimmed Surfaces, 254 on using the form.

When entered in the Create/Surface/Decompose form, the select menu that appears at the bottom of the

screen will show the following icons:

Point/Vertex/Edge Point/Interior Point. This will select a point for decomposing in the

order listed. If not point or vertex is found, the point closest to edge will be used or a point

will be projected onto the surface.

Use cursor select or directly input an existing point on the surface. If point is not on the

surface, it will be projected onto the surface.

Use to cursor select a point location on an edge of a trimmed surface.

Use to cursor select a point location inside a trimmed surface.

Use to cursor select a vertex of a trimmed surface.


Example

Figure 1-30 shows trimmed surface 4 with seven edges. We will decompose surface 4 into four four-sided

surfaces.

Figure 1-30 Trimmed Surface to be Decomposed

Our first decomposed surface will be surface 3, as shown in Figure 1-31. The figure shows surface 3

cursor defined by three vertex locations and one point location along an edge. The point locations can be

selected in a clockwise or counterclockwise direction.


40

Figure 1-31 Point Locations for Decomposed Surface 4

Figure 1-32 shows the remaining decomposed surfaces 5, 6 and 7 and the select menu icons used to cursor

define the surfaces. Again, the point locations can be selected in a clockwise or counterclockwise

direction.

Figure 1-32 Point Locations for Decomposed Surfaces 5, 6 and 7


Use Surface Display Lines as a Guide

Generally, the surface display lines are a good guide to where the trimmed surface can be decomposed.

MSC recommends increasing the display lines to four or more. The display lines are controlled under the

menus Display/Display Properties/Geometric. See Preferences>Geometry (p. 459) in the Patran

Reference Manual for more information.

Building B-rep Solids

Boundary represented (B-rep) solids are created by using the Geometry application’s Create/Solid/B-rep

form. See Creating a Boundary Representation (B-rep) Solid, 337 for more information on the form.

There are three rules to follow when you create a B-rep solid in Patran:

1. The group of surfaces that will define the B-rep solid must fully enclose a volume.

2. The surfaces must be topologically congruent. That is, the adjacent surfaces must share a common

edge.

3. The normal surface directions for the exterior shell must all point outward, as shown in

Figure 1-33. That is, the normals must point away from the material of the body. This will be done

automatically during creation as long as rules 1 and 26 are satisfied.

B-rep solids created in Patran can only be meshed with TetMesh.

Figure 1-33 Surface Normals for B-rep Solid

Important:At this time, Patran can only create a B-rep solid with an exterior shell, and no interior

shells.


42

Building Degenerate Surfaces and Solids

A bi-parametric surface can degenerate from four edges to three edges. A tri-parametric solid can

degenerate from six faces to four or five faces (a tetrahedron or a wedge, respectively).

The following describes the best procedures for creating a degenerate triangular surface and a degenerate

tetrahedron and a wedge shaped solid.

Building a Degenerate Surface (Triangle)

There are two ways you can create a degenerate, three-sided surface:

• Use the Create/Surface/Edge form with the 3 Edge option. See Creating Surfaces from Edges

(Edge Method) on using the form.

• Or, use the Create/Surface/Curve form with the 2 Curve option. See Creating Surfaces Between

2 Curves on using the form.

Figure 1-34 illustrates the method of using the Create/Surface/Curve form with the 2 Curve option.

Notice that the apex of the surface is defined by a zero length curve by using the Curve select menu icon

shown in Figure 1-34.

Figure 1-34 Creating a Degenerate Surface Using Create/Surface/Curve

Important:IsoMesh will create hexahedron elements only, if the solid has six faces. Some wedge

elements will be created for a solid with five faces. IsoMesh will create tetrahedron

elements only, for a solid with four faces. TetMesh will create tetrahedron elements only,

for all shaped solids.


Building a Degenerate Solid

Four Sided Solid (Tetrahedron)

A four sided (tetrahedron) solid can be created by using the Create/Solid/Surface form with the 2 Surface

option, where the starting surface is defined by a point for the apex of the tetrahedron, and the ending

surface is an opposing surface or face, as shown in Figure 1-35.

Five Sided Solid (Pentahedron)

A five sided (pentahedron) solid can be created by using:

• The Create/ Solid/Face form with the 5 Face option. See Creating Solids from Faces on using the

form.

• The Create/Solid/Surface form with the 2 Surface option. See Creating Solids from Surfaces

(Surface Method) on using the form.

Figure 1-36 and Figure 1-37 illustrate using the Create/Solid/Surface form to create the pentahedron and

a wedge.

Figure 1-35 Creating a Tetrahedron Using Create/Solid/Surface


44

Figure 1-36 Creating a Pentahedron Using Create/Solid/Surface

Figure 1-37 Creating a Wedge Using Create/Solid/Surface

Chapter 2: Accessing, Importing & Exporting Geometry


2 Accessing, Importing &

Exporting Geometry

� Overview 46

� Direct Geometry Access of CAD Geometry 47

� PATRAN 2 Neutral File Support For Parametric Cubic Geometry 57

Geometry Modeling - Reference Manual Part 2Overview

46

Overview

Patran can access geometry from an external CAD system user file. Geometry can also be imported (or

read) from a PATRAN 2 Neutral file or from an IGES file. Patran can export (or write) some or all

geometry to an external PATRAN 2 Neutral file or IGES file.

Geometry can be accessed or imported into the user database either by using the File/Import menus or by

using the File/CAD Model Access menus on the Patran main form. Geometry can be exported from the

database using the File/Export menus.

For more information on executing the File/Import and File/Export forms, see File>Import, 73 and

File>Export (p. 192) in the Patran Reference Manual.

For more information on accessing CAD models, see Direct Geometry Access of CAD Geometry, 47.

For more information on import and export support of geometry for the PATRAN 2 Neutral file, see

PATRAN 2 Neutral File Support For Parametric Cubic Geometry, 57.

For more information on which IGES entities are supported by Patran for importing and exporting, see

IGES Entities Supported for Import, 103 and Geometric Entity Types and their Supported IGES

Equivalents (p. 201) in the Patran Reference Manual.

47Chapter 2: Accessing, Importing & Exporting GeometryDirect Geometry Access of CAD Geometry

Direct Geometry Access of CAD Geometry

Patran can directly access geometry from an external CAD file for the following CAD systems that are

listed in Table 2-1.

This unique Direct Geometry Access (DGA) feature allows you to access the CAD geometry and its

topology that are contained in the CAD file. Once the geometry is accessed, you can build upon or modify

the accessed geometry in Patran, mesh the geometry, and assign the loads and boundary conditions as

well as the element properties directly to the geometry.

You can execute a specific Patran CAD Access module by using the File/Importing Models menus on

the main form. See File>Import (p. 73) in the Patran Reference Manual for more information.

For more information on using Patran ProENGINEER, see Importing Pro/ENGINEER Files (p. 134) in

the Patran Reference Manual.

For more information on using Patran Unigraphics, see Importing Unigraphics Files (p. 145) in the Patran

Reference Manual.

Accessing Geometry Using Patran Unigraphics

If Patran Unigraphics is licensed at your site, you can access the geometric entities from an external

EDS/Unigraphics part file.

Features of Patran Unigraphics

• Unigraphics part file can be accessed in Patran using one of two methods. The first method is

express file based import. The second method is direct parasolid transmit file based import. In

both cases, Unigraphics geometry is imported and stored in a Patran database.

• Patran uses the original geometry definitions of the accessed entities, without any

approximations. Parasolid evaluators are directly used for entities imported via the direct

parasolid method.

• CAD Access filters are provided that can be selected based on the defined EDS/Unigraphics

entity types, levels, and layers.

Table 2-1 Supported CAD Systems and Their Patran CAD Access Modules

Supported CAD System Patran CAD Access Module *

*Each Patran CAD Access module must be licensed before you can access the appropriate external

CAD file. You can find out which Patran products are currently licensed by pressing the

MSC.Software Corporation (MSC) icon on the main form, and then pressing the

License button on the form that appears.

EDS/Unigraphics Patran Unigraphics

Pro/ENGINEER by Parametric Technology Patran ProENGINEER

CATIA by Dassault Systemes Patran CATIA

Geometry Modeling - Reference Manual Part 2Direct Geometry Access of CAD Geometry

48

• You can automatically create Patran groups when accessing the geometry based on the defined

entity types, levels, or layers.

For more information on using Patran Unigraphics, see Importing Unigraphics Files (p. 145) in the Patran

Reference Manual.

Tips For Accessing EDS/Unigraphics Geometry for Express File Based Import

1. When you execute EDS/Unigraphics, make sure the solid to be accessed is topologically

congruent with no gaps (see Figure 2-1). For more information, see Topological Congruency and

Meshing, 13.

Verify that the edges of the solid’s adjacent faces share the same end points or vertices, and that

there are no gaps between the faces.

You can improve Patran Unigraphics’ performance by reducing the number of entities to be

processed by using the Entity Type filter on the Patran Import form and unselect or un-highlight

all entities of a particular type that you do not want, before you access the part file. For example,

you can unselect the entity type, “Bounded-Plane”, to eliminate all bounded plane entities. For the

direct parasolid import option, the entity type filter can be used for wire body/sheet body/solid

body only.

Put those entities in EDS/Unigraphics that you want to access into specific layers. Then select to

only those layers in the Patran Import form before importing the part.

Make sure the Patran Global Model Tolerance is reset to an appropriate value if you will be

accessing long thin surfaces and solids with small dimensions (default is 0.005). For example, set

the tolerance value so that it is smaller than the smallest edge length (greater than 10.0E-6) in the

model. This will improve model usability on some models.

Figure 2-1 Topologically Congruent Surfaces for Patran Unigraphics


Tips For Accessing Parasolid Geometry

This section provides helpful hints and recommendations regarding the usage of Patran as it pertains to

Parasolid integration.

Solid Geometry Guidelines

Disassembling Solids

The Edit/Solid/Disassemble function in the Geometry Application can be used

to create simply trimmed surfaces (green 4-sided) with one command. This can

be a big timesaver if the B-rep Solid is being disassembled to eventually create

tri-parametric solids (blue) for Hex meshing. This command will convert all 4-

sided B-rep Solid faces into simply trimmed surfaces (green) which then can

be used to construct tri-parametric solids.

Solids Break If difficulties are encountered in breaking a solid:

1. First disassemble the original solid (Edit/Solid/Disassemble).

2. Try to reconstruct a new solid using Create/Solid/B-rep. If this is

unsuccessful due to gaps between surfaces, use the Edit/Surface/Sew

and try again. If a solid is created, continue with the break operation.

3. If steps (a) and (b) were unsuccessful:

• Break the trimmed surfaces from the disassembled solid (step (a)). If this

operation is slow, refit the surfaces (Edit/Surface/Refit) before the break

operation.

• Create the additional surfaces in the interior required to enclose the

individual solid volumes.

• Create the new individual solids using Create/Solid/B-rep. If the B-rep can

not be created due to surface gaps, use Edit/Surface/Sew and try again.

Global Model Tolerance

After successful access of Unigraphics geometry via the Parasolid Direct

method, the Global Model Tolerance will be set relative to the models

geometric characteristics. This tolerance is the recommended tolerance for

Patran applications to use for best results.

Solids - Group Transform

Group transform for solids is not supported. For information about

transforming solids in pre-release format, see , 50.


50

Meshing Guidelines

Hybrid TetMesher - Global Edge Lengths

The Hybrid tetmesher only accepts global edge lengths for mesh criteria if

attempting to directly mesh a solid. If you encounter difficulties, decrease the global

edge length.

Hybrid TetMesher - Mesh Control

The Hybrid tetmesher does not write nodes that lie on solid edges into the mesh seed

table. This limits the ability of the Hybrid tetmesher to recognize existing meshes.

For example, if your requirements are: (1) to match adjacent meshes (i.e., multiple

solids); (2) that the mesh be able to recognize a hard curve/point; or (3) to define

mesh seed prior to solid meshing, follow these steps:

• Define any desired hard points/curves and mesh seeds.

• Surface mesh the geometry using the paver, creating triangular elements which

completely enclose the desired geometric volume.

• Invoke the Hybrid tetmesher, using the previously created triangular elements as

input.

Paver If the paver exhibits difficulties meshing some geometry or making congruent

meshes:

• Delete any existing mesh on the problematic geometry.

• Perform an Edit/Surface/Refit.

• Do an Edit/Surface/Edge Match if congruency is an issue.

• Mesh again.


PRE-RELEASE CAPABILITY: Solid Geometry Guidelines

Solids - Group

Transform

Group transform for solids is not supported. If a transformed solid is required,

consider the following alternatives: (1) Perform the transformation in the native

CAD system and then again access the desired geometry in Patran; (2) Enable an

environment variable before executing Patran. At the system prompt, type:

setenv P3_UG_ENTITY_FILTER 1

which allows the transformation of Parasolid solid geometry and perform the

transformation. If a solid is successfully constructed, continue as planned. If not,

either:

• Mesh the original solid and transform the resulting finite element mesh, with

the limitation being that element properties and loads/boundary conditions

will have to be assigned directly to the finite elements; or

• Try to reconstruct a B-rep solid from the constituent surfaces that result from

the transformation, by first using Geometry tools such as Edit/Surface/Sew,

Edit/Surface/Edge Match, etc., to reconnect the surfaces and then use

Create/Solid/B-rep.

• Initially access the original geometry (Unigraphics only) using the Express

Translation method. If a solid is successfully imported, a transformation of

the geometry is supported.

Surface/Curve Geometry Guidelines

Surface Congruency Unigraphics does not automatically enforce surface congruency. Typically,

CAE applications require congruent meshes; therefore, geometric surfaces

must usually be congruent. Accessing geometry through Parasolid simply

retrieves the Unigraphics geometry exactly as it is defined; an explicit action

must be taken to sew geometric surfaces, otherwise they will not be congruent.

It is recommended that models with surfaces be sewn up in Unigraphics prior

to access by Patran. Patran offers the ability to also invoke the Unigraphics

surface sew tool; in fact, this is the default operation when accessing Sheet

Bodies.

Unigraphics Sew With Verify During Geometry Access

“Unigraphics Sew” and “Verify Boundary” toggles are, by default, ON during

import. The Verification entails placement of markers at all incongruent

surface edges, thus allowing a user to quickly identify whether the Unigraphics

Sew was completely (or partially) successful. The markers may be removed

using the Broom icon.


52

Problem Unigraphics Entities From Import

Patran detects three different types of anomalies during Unigraphics part file

import:

a) Suspect939 Entities: Sometimes Unigraphics needs to take special actions

to convert surfaces from earlier version parts. These surfaces are attributed

with “Suspect939.” Although for the most part these surfaces are usable,

Unigraphics recommends that these surfaces be replaced. As such, Patran will

not attempt to include these surfaces in the Unigraphics sewing, and we

recommend that these surfaces be refitted once imported into Patran. You will

find these surfaces in a group named, <model_name>_UG_SUSPECT.

b) Invalid Entities: Before importing the Unigraphics model, Patran will check

each surface and curve entities to ensure consistency and validity.

Occasionally, some entities do not pass the checks. These invalid entities will

be excluded from both UG sewing and Patran import. If you see such a

message in the invoke window, you should go back to UG to ensure the model

is valid. Please reference the next section, Unigraphics Model Checks, 53 for

steps to do this check. One recommended way is to refit/reconstruct the surface

in Unigraphics and then reimport it into Patran.

If UG sewing is turned on for the Patran import, there is a chance that invalid

entities are created by the UG sew. These entities will be brought into Patran

and put into a group named, <model_name>_UG_INVALID. As there is no

guarantee that entities in this group will work with any applications, we

strongly recommend you first commit/save the Patran database and then

reconstruct these bodies if possible.

c) Gap Surfaces: Sometimes surfaces, that are degenerate or are/close to being

zero area, appear in the model. These surfaces are called “gap surfaces.” If

there are any such gap surfaces, they will be in a group named,

<model_name>_GAP_SURFACE. Please inspect the imported model and

determine if these gap surfaces should be removed from the model.



Unigraphics Model Checks

Unigraphics provides geometry evaluation tools which are extremely useful in

judging the quality of a model. Here are some geometry/topology checks

Unigraphics can perform and provide results with any UG part: (1) In

Unigraphics V13.0, “Info” is available at the top menu bar, under

Info/Analysis/Examine Geometry. If you use this on surfaces and any are ill-

defined, they will be flagged as “suspect”. (2) In Unigraphics V13.0, Info is

available at the top menu bar. To run all checks:

• Use Info->Analysis->Examine Geometry...

• Choose “Set All Checks”, then “OK”.

• Choose “Select All” to check the entire model currently selectable.

• NOTE: Default Distance tolerance is 0.001 units and Default Angle

tolerance is 0.5 units.

Patran Surface Sew In addition to accessing the Unigraphics surface sew tool, Patran offers an

additional capability to sew surfaces beyond what Unigraphics supports (e.g.,

resolution of T-edges). If the Unigraphics surface sew does not resolve all

incongruences, try using the Patran surface sew as well. This capability can be

accessed through Edit/Surface/Sew in the Geometry application. If both the

Unigraphics and Patran surface sew tools cannot remove all of the gaps and

incongruencies, then two options are available. The first option is to refit all of

the surfaces (Edit/Surface/Refit). Sometimes, after this operation, these

surfaces can be sewn together (Edit/Surface/Sew).

The other option for sewing the model using Patran surface sewing is to

increase the global tolerance in Patran and sew the model again. Changing the

global tolerance in Patran is generally not recommended, but in this case may

be necessary. The necessity of increasing the global tolerance is determined by

checking the incongruent edges of the model (Verify/Surface/Boundary) to see

if they share vertices, or by the gap closure operation when gaps cannot be

closed between surface since the edge curves are too far apart. The tolerance

value should be set to a value just larger than the distance between the vertices

to be equivalenced (vertices which should be shared at the ends of incongruent

curves), or just larger than the “allowable gap closure tolerance” which is

issued by the sewing (or edge match) operation.

(Note that there are cases where sewing will report that gaps exist which are

not really gaps. This is because the operation of checking for gaps does not

necessarily know about the engineering intent of the model. We suggest that

the user check the gaps reported to make sure that they are gaps. Furthermore,

we suggest that the global tolerance be increased conservatively, e.g., double

the tolerance instead of increasing it by an order of magnitude.)



54

Accessing Geometry Using Patran ProENGINEER

If Patran ProENGINEER is licensed at your site, you can access the geometric entities from an external

Pro/ENGINEER part file.

You can execute Patran ProENGINEER either from Patran or from Pro/ENGINEER by doing one of the

following:

Refitting Geometry The technique of refitting geometry has been identified as a potentially viable

method of removing problematic geometry that prevents subsequent meshing,

application of LBC’s, editing, transforming, etc. Edit/Curve/Refit and

Edit/Surface/Refit are available under the Geometry application. These

functions will more regularly parameterize poorly parameterized geometry

(for surfaces, this typically involves those with compound curvature), which

can currently lead to difficulties in successfully building CAE models.

Congruency and boundary definitions are retained.

Edit/Surface/Refit As previously mentioned, the Edit/Surface/Refit function in the Geometry

application can be used to successfully handle problematic Sheet Body

geometry. The situations where this applies include:

• Accessing geometry with the Unigraphics Sew option disabled with

subsequent attempts to make the surfaces congruent by using Patran’s

surface sew, edge match, etc.

• Difficulties rendering, meshing, edge matching, disassembling,

transforming, etc.

• Surfaces that result from disassembling solid geometry (i.e., for regioning).

Curves Coincident With Surface and Solid Edges

Wire Bodies coincident with Sheet Body and Solid Body edges are not

equivalenced. This is a different behavior from what occurs if the “Express

Translation” method is used. If coincident curves are not detected by the user,

they may, for example, apply a Loads/Boundary Condition to what they

believe is a surface or solid edge, when in fact they are applying it to a curve.

To avoid this situation:

• Move all Wire Bodies to a separate group and post only when required.

• If Wire Bodies are accessed, use the new Geometry function

Edit/Point/Equivalence to connect the curve and surface/solid vertices.

• Disable access of Wire Bodies and only access when needed.



Executing Patran ProENGINEER From Patran

Execute Patran ProENGINEER from Patran by using the File/Import... menu and make sure the

Pro/ENGINEER button is pressed on the Import form. See Importing Pro/ENGINEER Files (p. 134) in the

Patran Reference Manual for more information.

Executing Patran ProENGINEER From Pro/ENGINEER

Execute Patran ProENGINEER from Pro/ENGINEER by doing the following:

1. Execute Pro/ENGINEER by entering:

p3_proe

p3_proe will ask for the command name to run Pro/ENGINEER. Press <CR> if you want to

accept the default command pro.

Enter the command name for running Pro/ENGINEER.[pro]?: <cr>Open the Pro/ENGINEER assembly file or part file. Then, select the Pro/ENGINEER menus in the following order:

File

Export

Model

Patran Geom

The Patran menu will list four options:

Filter

Run Patran

Create .db

Create .geo

You can select any one of the above four options.

If Filter is selected:

• A menu appears which allows the user to select:

Datum Points

Datum Curves

Datum Surfaces

Datum Planes

Coordinate System Datums

for output to the intermediated .geo file. (Default = no datum entities).

If Run Patran is selected:

Note: Make sure Patran ProENGINEER has been properly installed by following the instructions

in Module and Preference Setup (Ch. 3) in the Patran Installation and Operations Guide


56

• A Patran ProENGINEER intermediate.geo file will be created from the current

Pro/ENGINEER object in memory.

• Patran will automatically be executed and a database will be created and opened.

• The Patran ProENGINEER intermediate.geo file containing the Pro/ENGINEER geometry

will be loaded into the Patran database, and both Pro/ENGINEER and Patran will remain

executing.

If Create .db is selected:

• A Patran ProENGINEER intermediate.geo file will be created from the current

Pro/ENGINEER object in memory.

• A batch job will be submitted in background mode that will:

One, execute Patran and create and open a database.

Two, load the.geo file into the Patran database.

And, three, close the database and exit Patran.

If Create .geo is selected, a Patran ProENGINEER intermediate.geo file will be created from the

current Pro/ENGINEER object in memory.

For more information on the Patran ProENGINEER intermediate.geo file, see Executing Patran

ProENGINEER From Pro/ENGINEER (p3_proe) (p. 143) in the Patran Reference Manual.

57Chapter 2: Accessing, Importing & Exporting GeometryPATRAN 2 Neutral File Support For Parametric Cubic Geometry

PATRAN 2 Neutral File Support For Parametric Cubic Geometry

The PATRAN 2 Neutral file is supported by MSC.Software Corporation’s Patran.

With the PATRAN 2 neutral file, Patran can import or export only parametric cubic geometry by

executing the File/Import menus on the main form.

Patran cannot export non-parametric cubic geometry using the PATRAN 2 Neutral file. Instead, you may

use export the entire geometry model using the IGES file.

Depending on Geometry application methods used to create the geometry, you may or may not be able

to create parametric cubic curves, surfaces or solids. Also, some geometry Create action methods can

generate only parametric cubic geometry.

For information on how to import or export a PATRAN 2 Neutral file, see Importing PATRAN 2.5 Neutral

Files, 88 and Exporting to a PATRAN 2.5 Neutral File (p. 192) in the Patran Reference Manual.

For the definition of parametric cubic geometry, see Parametric Cubic Geometry.

For information on what types of curves, surfaces and solids you can create in Patran, see Table 1-1, and

starting on (p. 28).

For more information on how to export an IGES file, see Exporting to IGES Files (p. 201) in the Patran

Reference Manual.

Geometry Modeling - Reference Manual Part 2PATRAN 2 Neutral File Support For Parametric Cubic Geometry

58

Chapter 3: Coordinate Frames


3 Coordinate Frames

� Coordinate Frame Definitions 60

� Overview of Create Methods For Coordinate Frames 64

� Translating or Scaling Geometry Using Curvilinear Coordinate

Frames 67

Geometry Modeling - Reference Manual Part 2Coordinate Frame Definitions

60

Coordinate Frame Definitions

Patran can create and support three types of coordinate frames:

• Rectangular (X,Y,Z)

• Cylindrical (R, Theta, Z)

• Spherical (R, Theta, Phi)

Patran also has a default global rectangular coordinate frame, Coord 0. Coord 0 is the default reference

coordinate frame for many application forms (which can be changed to another coordinate frame). Also,

Coord 0 cannot be deleted, even if specified.

Each coordinate system defined in Patran has three principal axes. These axes define how spatial

locations are determined in that coordinate system, and are internally numbered 1, 2 and 3. The meaning

of each principal axis depends on if the coordinate frame is rectangular, cylindrical or spherical.

When a coordinate frame is created, its principal axes and its orientation are displayed at the appropriate

location on the model. The ID of the coordinate frame is also displayed at the coordinate frame’s origin.

Rectangular Coordinate Frame

Figure 3-1 shows the principal axes of a rectangular coordinate frame and a point, P, in rectangular space.

In a rectangular frame, the principal axes 1, 2 and 3 correspond to the X, Y and Z axes, respectively.

Points in space specified in a rectangular coordinate frame are entered in the order: x-coordinate, y-

coordinate and z-coordinate.

Important:Coordinate frame angles for the cylindrical and spherical coordinate frames (that is, and

) are expressed in degrees. Special conditions apply when defining

spatial functions in cylindrical or spherical coordinate frames. For more information, see

Procedures for Using Fields (p. 195) in the Patran Reference Manual.

θ

Φ

61Chapter 3: Coordinate FramesCoordinate Frame Definitions

Figure 3-1 Rectangular Coordinate Frame

Cylindrical Coordinate Frame

Figure 3-2 shows a cylindrical frame in which the principal axes 1, 2 and 3 correspond to the R, T ( )

and Z axes, respectively. Points specified in a cylindrical coordinate frame are entered in the order:

radial-coordinate, theta-coordinate and z-coordinate.

θ

Geometry Modeling - Reference Manual Part 2Coordinate Frame Definitions

62

Figure 3-2 Cylindrical Coordinate Frame

Spherical Coordinate Frame

Figure 3-3 shows a spherical frame in which the principal axes 1, 2 and 3 correspond to the R, T ( ) and

P ( ) axes, respectively. Points specified in a spherical coordinate frame are entered in the order: radial-

coordinate, theta-coordinate, and phi-coordinate.

A node’s local directions (1, 2, 3) can vary according to its position within the spherical coordinate frame.

For example:

See Input LBCs Set Data (Static Load Case) (p. 36) in the Patran Reference Manual.

If node lies along R direction, then dir 1 of node is along +R

If node lies along R direction, then dir 2 of node is along -P

If node lies along R direction, then dir 3 of node is along +T

If node lies along T direction, then dir 1 of node is along +T

If node lies along T direction, then dir 2 of node is along -P

If node lies along T direction, then dir 3 of node is along -R

If node lies along P direction, then dir 1 of node is along +P

If node lies along P direction, then dir 2 of node is along +T

If node lies along P direction, then dir 3 of node is along -R

θ

Φ

63Chapter 3: Coordinate FramesCoordinate Frame Definitions

Figure 3-3 Spherical Coordinate Frame Definition

Geometry Modeling - Reference Manual Part 2Overview of Create Methods For Coordinate Frames

64

Overview of Create Methods For Coordinate Frames

There are six ways you can create a local rectangular, cylindrical or spherical coordinate frame in Patran.

They are listed as separate methods under the Geometry Application’s Create action:

• 3Point

• Axis

• Euler

• Normal

• 2Vector

• View Vector

For more information on using the application forms for the Create methods, see Creating Coordinate

Frames.

You can also create coordinate frames using the Transform action’s Translate and Rotate methods. For

more information, see Transforming Coordinate Frames.

The following sections briefly discuss the Create methods for coordinate frames.

3 Point Method

Figure 3-4 illustrates using the Create action’s 3 Point method for creating a coordinate frame by

specifying three points:

Figure 3-4 Coordinate Frame Creation Using the 3 Point Method

Axis Method

Figure 3-5 illustrates using the Axis method to create a coordinate frame by specifying a point location

at the origin, a point location on axis 1, 2, or 3, and a point location on one of the two remaining axes.

65Chapter 3: Coordinate FramesOverview of Create Methods For Coordinate Frames

Figure 3-5 Coordinate Frame Creation Using the Axis Method

Euler Method

The Euler Create action creates a new coordinate frame through three rotations from an existing

coordinate frame. Specifically, the following steps are performed in the order shown:

1. Input the reference coordinate frame ID.

1. Enter the point location of the coordinate frame’s origin.

1. Enter the axis and rotation angle for Rotation 1.



The final orientation of the new coordinate frame depends on the order of rotations that are made.

Normal Method

Figure 3-6 illustrates using the Normal method to create a coordinate frame, where its origin is at a point

location on a surface. The positive axis 3 direction is normal to the surface by using right-hand rule and

crossing the surface’s parametric direction with the direction. The axis 1 direction is along the

surface’s direction and the axis 2 direction is orthogonal to axis 1 and 3.

For more information on the definition of the parametric and axes, see Parameterization.

ξ1

ξ2

ξ1

ξ1

ξ2

Geometry Modeling - Reference Manual Part 2Overview of Create Methods For Coordinate Frames

66

Figure 3-6 Coordinate Frame Creation Using the Normal Method

67Chapter 3: Coordinate FramesTranslating or Scaling Geometry Using Curvilinear Coordinate Frames

Translating or Scaling Geometry Using Curvilinear Coordinate Frames

You can translate or scale geometry in Patran by using the Transform action’s Translate method or Scale

method. For information and examples on using either form, see Translating Points, Curves, Surfaces,

Solids, Planes and Vectors or Scaling Points, Curves, Surfaces, Solids and Vectors.

On either form, you can choose either the Cartesian in Refer. CF toggle or the Curvilinear in Refer. CF

toggle.

If Curvilinear in Refer. CF is chosen, you can specify either an existing cylindrical or spherical

coordinate frame as the reference, and the translation vector or the scale factors will be interpreted as R,

, Z for the cylindrical system, and as R, , for the spherical system. (Both the axis and axis are

measured in degrees.)

Figure 3-7 throughFigure 3-10 are examples of using the Translate and Scale methods with the

Curvilinear in Refer. CF toggle.

Figure 3-7 Translate Method where Surface 1 is Translated <1 90 0> within Cylindrical

Coordinate Frame 1

θ θ Φ θ Φ

Geometry Modeling - Reference Manual Part 2Translating or Scaling Geometry Using Curvilinear Coordinate Frames

68

Figure 3-8 Scale Method where Curve 1 is Scaled <2 1 1> within Cylindrical Coordinate

Frame 1


Frame 1

69Chapter 3: Coordinate FramesTranslating or Scaling Geometry Using Curvilinear Coordinate Frames


Frame 1

Points along the z-axis of a cylindrical coordinate system and at the origin of a spherical coordinate

system cannot be transformed uniquely in the (cylindrical) or and (spherical) coordinates

respectively. This is due to the fact that there is no unique for points on the z-axis of a cylindrical

coordinate system or and coordinates at the origin of a spherical coordinate system. Therefore, in

Patran, any point on the z-axis of a cylindrical coordinate system or at the origin of a spherical coordinate

system is not transformed.

θ θ φ

θ

θ φ

Geometry Modeling - Reference Manual Part 2Translating or Scaling Geometry Using Curvilinear Coordinate Frames

70

Chapter 4: Create Actions


4 Create Actions

� Overview of Geometry Create Action 72

� Creating Points, Curves, Surfaces and Solids 78

� Creating Solid Primitives 311

� Feature Recognition (Pre-release) 350

� Creating Coordinate Frames 393

� Creating Planes 407

� Creating Vectors 433

� Creating P-Shapes 450

� Edit P-Shapes 460

Geometry Modeling - Reference Manual Part 2Overview of Geometry Create Action

72

Overview of Geometry Create Action

Select any method to obtain detailed help.

Object Method Description

Point • XYZ • Creates points from their cartesian coordinates or from existing

nodes or vertices.

• ArcCenter • Creates a point at the center of curvature of the specified curves.

• Extract • Creates points on existing curves at a parametric coordinate

location.

• Interpolate • Creates one or more points between two existing point locations that

are uniformly or nonuniformly spaced apart.

• Intersect • Creates points at the intersection of any of the following pairs of

entities: Curve/Curve, Curve/Surface, Curve/Plane, Vector/Curve,

Vector/Surface, Vector/Plane.

• Offset • Creates a point on an existing curve.

• Pierce • Creates a point at the location where a curve intersects or pierces a

surface or solid face.

• Project • Creates points from an existing set of points or vertices that are

either projected normally or projected through a defined vector or

projected through the current view angle, onto an existing surface or

solid face.

73Chapter 4: Create ActionsOverview of Geometry Create Action

Curve • Point • Creates curves through two, three or four point locations.

• Arc3Point • Creates arced curves through a starting, middle and ending point

locations.

• Chain • Creates a chained composite curve from two or more existing

curves. Usually used for creating trimmed surfaces.

• Conic • Creates a conic curve based on a defined altitude and focal point and

a starting and ending points.

• Extract • Creates a curve on an existing surface either at a parametric

coordinate location or on an edge of the surface.

• Fillet • Creates a fillet curve with a defined radius between two existing

curves or edges.

• Fit • Creates a curve that passes through a set of point locations based on

a least squares fit.

• Intersect • Creates a curve at the intersection of two surfaces or solid faces.

• Manifold • Creates a curve on a a surface or solid face that is between two or

more point locations.

• Normal • Creates a curve that is normal from an existing surface or solid face

to a point location.

• Offset • Creates either constant or variable offset curves from an existing

curve.



74

Curve (cont.)

• Project • Creates curves from an existing set of curves or edges that is

projected onto a surface either normally or from a defined plane or

vector or based on the current view angle.

• PWL • Creates contiguous straight curves between two or more point

locations.

• Spline • Creates a spline curve that passes through two or more point

locations.

• TanCurve • Creates a curve that is tangent between two curves or edges.

• TanPoint • Creates a curve from a point location to a tangent point on a curve.

• XYZ • Creates a curve at a defined origin based on a vector that defines its

length and orientation.

• Involute • Creates involute curves either using an Angles option or a Radii

option.

• Revolve • Creates curves that are rotated from point locations about a rotation

axis for a defined angle.

• 2D Normal • Creates straight curves that are perpendicular to an existing curve or

edge and that lies within a defined plane.

• 2D Circle • Creates a circle within a defined plane.

• 2D

ArcAngles

• Creates arced curves within a defined 2D plane.

• 2D Arc2Point • Creates an arced curve that lies within a defined plane and that uses

a starting, ending and center point locations.

• 2D Arc3Point • Creates an arced curve that lies within a defined plane and that

passes through a starting, middle and ending point locations.



Surface • Curve • Creates surfaces that passes through either two, three, four or N

curves or edges.

• Composite • Create surfaces that are composed from multiple surfaces.

• Decompose • Creates surfaces from an existing surface (usually a trimmed

surface) based on four cursor defined vertices that lie on the existing

surface.

• Edge • Creates surfaces from three or four curves or edges.

• Extract • Creates a surface within a solid based on either the parametric

coordinate location or on the face of the solid.

• Fillet • Creates a filleted surface with one or two defined radii between two

existing surfaces or faces.

• Match • Creates a surface that is topologically congruent with one of the two

specified surfaces.

• Offset • Creates constant offset surfaces from an existing surface.

• bordered • Creates a surface that is created between two existing curves or

edges.

• Trimmed • Creates a trimmed surface that consist of an outer chained curve

loop and optionally, an inner chained curve loop.

Surface (cont.)

• Vertex • Creates a surface from four point locations.

• XYZ • Creates a surface at a defined origin based on a vector that defines

its length and orientation.

• Extrude • Creates a surface from an existing curve or edge that is extruded

through a vector and is optionally scaled and rotated.

• Glide • Creates a surface that is created from a specified director curve or

edge, along one or more base curves or edges.

• Normal • Creates surfaces from existing curves through a defined thickness.

• Revolve • Creates surfaces that are rotated from curves or edges about a

rotation axis for a defined angle.

• Mesh • Creates a surface from a congruent 2-D mesh (shell mesh).

• P-Shape • Creates a surface (rectangle, triangle, cyclinder, sphere, six-sided

box, quadrilateral, disk, cone, paraboloid, or five-sided box) with

user input.



76

Solid • Primitive • Creates a solid (block, cylinder, cone, sphere or torus) with user

input a point, length, width, height, and reference coordinate frame.

It also provides an option to perform boolean operation with the

input target solid using the created block, cylinder, cone, sphere or

torus as the tool solid.

• Surface • Creates solids that pass through two, three, four or N surfaces or

faces.

• B-rep • Creates a B-rep solid from an existing set of surfaces that form a

closed volume.

• Decompose • Creates solids from two opposing solid faces by choosing four

vertex locations on each face.

• Face • Creates solids from five or six surfaces or faces.

• Vertex • Creates solids from eight point locations.

• XYZ • Creates a solid at a defined origin based on a vector that defines its

length and orientation.

• Extrude • Creates a solid from an existing surface or face that is extruded

through a vector and is optionally scaled and rotated.

• Glide • Creates a solid that is created from a specified director curve or

edge, along one or more base surfaces or faces.

• Normal • Creates solids from existing surfaces through a defined thickness.

• Revolve • Creates solids that are rotated from surfaces or faces about a rotation

axis for a defined angle.

Coord • 3Point • Creates a rectangular, cylindrical or spherical coordinate frame

based on defined point locations for its origin, a point on Axis 3 and

a point on Plane 1-3.

• Axis • Creates a rectangular, cylindrical or spherical coordinate frame

based on point locations that define the original and either points

one Axis 1 and 2, Axis 2 and 3, or Axis 3 and 1

• Euler • Creates a rectangular, cylindrical or spherical coordinate frame

based on three rotation angles about Axes 1, 2 and 3.

• Normal • Creates a rectangular, cylindrical or spherical coordinate frame

whose Axis 3 is normal to a specified surface or solid face, and

whose origin is at a point location.



Plane • Vector

Normal

• Creates a plane from a specified point as the plane origin and a

specified direction as the plane normal.

• Curve

Normal

• Creates a plane from a point on or projected onto a specified curve

as the plane origin and the curve tangent at that point as the plane

normal.

• Interpolate • Creates a plane from the interpolating points on a specified curve as

the plane origins and the curve tangents at those points as the plane

normals.

• Least Squares • Creates a plane from the least square based on three and more

specified non-colinear points.

• Offset • Creates a plane that is parallel to a specified plane with a specified

offset distance.

• Surface

Tangent

• Creates a plane from a specified point on or projected to a specified

surface as the plane origin and the surface normal at that location as

the plane normal.

• 3 Points • Creates a plane from three specified non-colinear points. The plane

origin is located at the first point.

• Point-Vector • Creates planes at a point and normal to a vector.

Vector • Magnitude • Creates a vector by specifying the vector base point, the vector

direction and the vector magnitude of the desired vector.

• Intersect • Creates a vector along the intersecting line of two specified planes.

The vector base point is the projection of the first plane origin on

that intersecting line.

• Normal • Creates a vector that has the direction parallel to a specified plane

and the base point at a specified point on or projected onto that

plane.

• Product • Creates a vector that is the cross product of two specified vectors

and has its base point located at the base point of the first vector.

• 2 Point • Creates a vector that starts from a specified base point and pointing

to a specified tip point.


Geometry Modeling - Reference Manual Part 2Creating Points, Curves, Surfaces and Solids

78

Creating Points, Curves, Surfaces and Solids

Create Points at XYZ Coordinates or Point Locations (XYZ Method)

The XYZ method creates points from their cartesian coordinates or at an existing node, vertex or other

point location as provided in the Point select menu.

79Chapter 4: Create ActionsCreating Points, Curves, Surfaces and Solids

Tip: More Help

• Select Menu (p. 35) in the Patran Reference Manual

• Topology

• Coordinate Frame Definitions

Point XYZ Method Example

Creates Point 6 using the Create/XYZ method that is located at the global rectangular coordinates X =

10, Y = 5 and Z = 3.125.

Point XYZ Method On a Surface Example

Creates Point 5 using the Create/XYZ/Point select menu icons listed below which locates Point 5 on

Surface 1, whose exact location is cursor defined.


80

Point XYZ Method At Nodes Example

Creates Points 1 through 4 using the Create/XYZ/Point select menu icon listed below which locates the

points at Nodes 10 through 13.


Point XYZ Method At Screen Location Example

Creates Points 1 through 5 using the Create/XYZ/Point select menu icon listed below which locates

Points 1 through 5 by cursor defining them on the screen.


82

Create Point ArcCenter

The ArcCenter method creates a point at the center of curvature of the specified curves which have a non-

zero center/radius of curvature.


Tip: More Help:


• Topology

Point ArcCenter Method Example

Creates point 3 using Create/Point/Arc Center which locates point 3 in the center of the arc.


84

Extracting Points

Extracting Points from Curves and Edges

Creates points on an existing set of curves or edges at the parametric coordinate location of the curve

or edge, where has a range of .

ξ1

ξ1

0 ξ1

1≤ ≤


Point Extract Method Example

Creates Point 7 using the Create/Extract method, where the point is located at is equal to 0.75, on

Curve 1. Notice that the curve’s parametric direction arrow is displayed.

ξ1u( )


86

Point Extract Method Example

Creates Point 5 using the Create/Extract method, where the point is located at is equal to 0.75, on

the edge of Surface 1.

ξ1u( )


Extracting Single Points from Surfaces or Faces

Creates single points on an existing set of surfaces or faces at a specified u,v parametric location on the

surface.


88

Point Extract from Surfaces or Faces Method Example

Creates Point 5 using the Create/Extract Point from Surface or Face method, where the point is located

at is equal to 0.333 and is equal to 0.666, on Surface 1. ξ1u( ) ξ

2v( )


Extracting Multiple Points from Surfaces or Faces

Creates multiple points on an existing set of surfaces or faces where the bounds of the grid of points is

defined by a diagonal of two points.


90

Multiple Point Extract from Surfaces or Faces Diagonal Method Example

Creates Points 7 through 28 on Surface 1 in the bounds defined by points 5 and 6.


Extracting Multiple Points from Surfaces or Faces

Creates multiple points on an existing set of surfaces or faces where the bounds of the grid of points is

defined by a parametric , diagonal.ξ ξ2


92

Multiple Point Extract from Surfaces or Faces Parametric Method Example

Creates Points 5 through 28 on Surface 1 in the bounds defined by u-min=0.333, u-max=0.666, v-

min=0.333, and v-max=0.666.


Parametric Bounds for Extracting Points from a Surface


94

Interpolating Points

Between Two Points

The Interpolate method using the Point option will create n points of uniform or nonuniform spacing

between a specified pair of point locations, where n is the number of interior points to be created. The

point location pairs can be existing points, vertices, nodes or other point location provided by the Point

select menu.


Tip: More Help:


• Topology

Point Interpolate Method With Point Option Example

Creates five interior points starting with Point 3 that are between Points 1 and 2, using the

Create/Interpolate/Point option. The spacing is nonuniform at L2/L1 = 2.0.


96

Point Interpolate Method With Point Option Example

Same as the previous example, except the five new points are uniformly spaced between Nodes 1 and 2,

by using the Point select menu icon listed below.


Interpolating Points on a Curve

The Interpolate method using the Curve option creates n points along an existing curve or edge of

uniform or nonuniform spacing where n is the number of interior points to be created.


98

Tip: More Help:


• Topology

• Connectivity

• Display>Geometry (p. 377) in the Patran Reference Manual


Point Interpolate Method With Curve Option Example

Creates five uniformly spaced interior points, starting with Point 6 on Curve 1, using the

Create/Point/Interpolate/Curve option.

Point Interpolate Method With Curve Option Example

Creates Points 5 through 9 that are nonuniformly spaced by using the Create/Interpolate/Curve option,

where the points are created on an edge of Surface 1.


100

Intersecting Two Entities to Create Points

The Intersect method creates points at the intersection of any of the following pairs of entities:

Curve/Curve, Curve/Surface, Curve/Plane, Vector/Curve, Vector/Surface, Vector/Plane. One point will

be created at each intersection location. The pair of entities should intersect within a value defined by the

Global Model Tolerance. If the entities do not intersect, Patran will create a point at the closest approach

on each specified curve, edge, or vector for the Curve/Curve and Vector/Curve intersection options.


Tip: More Help:


• Topology

• Preferences Commands (p. 431) in the Patran Reference Manual

Point Intersect Method At An Edge Example

Creates Point 17, using the Create/Intersect method, at the intersection of Curve 3 and an edge of Surface

1.


102

Point Intersect Method with Two Curves Example

Creates Points 1 and 2, using the Create/Intersect method, at the intersection of Curves 1 and 2.


Point Intersect Method with Two Curves Example

Creates Points 1 and 2, using the Create/Intersect method. Because the curves do not intersect, Points 1

and 2 are created at the closest approach of the two curves.


104

Point Intersect Method with a Curve and a Surface Example

Creates Points 1, 2 and 3 using the Create/Intersect method at the intersection of Curve 6 with Surface 1.


Point Intersect Method with a Curve and a Plane Example

Creates Points 1, 2, and 3 using the Create/Intersect method at the intersection of Curve 2 with Plane 1.


106

Point Intersect Method with a Vector and a Curve Example

Creates Points 1, 2, and 3 using the Create/Intersect method at the intersection of Vector 1 with Curve 2.


Point Intersect Method with a Vector and a Curve Example

Creates Point 1 on Vector 1 and Point 2 on Curve 2, using the Create/Intersect method. Since the entities

do not intersect, Points 1 and 2 are created at the closest approach between the Vector and the Curve.


108

Point Intersect Method with a Vector and a Surface Example

Creates Points 1 and 2 using the Create/Intersect method at the intersection of Vector 1 and Surface 1.


Point Intersect Method with a Vector and a Plane Example

Creates Point 1 using the Create/Intersect method at the intersection of Vector 2 and Plane 1.


110

Creating Points by Offsetting a Specified Distance

The Offset method creates a point on an existing curve by offsetting a specified model space distance

from an existing point on the same curve.


Tip: More Help:


• Topology


Point Offset Method Example

Creates point 3 on curve one, .75 units from point 1 using Create/Point/Offset.


112

Piercing Curves Through Surfaces to Create Points

The Pierce method creates points at the intersection between an existing curve or edge and a surface or

solid face. The curve or edge must completely intersect with the surface or solid face. If the curve or edge

intersects the surface or face more than one time, Patran will create a point at each intersection.


Tip: More Help:


• Topology

Point Pierce Method Example

Creates Point 15, using the Create/Pierce method at the location where Curve 3 intersects Surface 1.


114

Point Pierce Method Example

This example is the same as the previous example, except the curve is defined by Points 13 and 14 by

using the Curve select menu icon listed below.


Projecting Points Onto Surfaces or Faces

The Project method creates points by projecting an existing set of points onto a surface or solid face

through a defined Projection Vector. New points can be projected from other points, vertices, nodes or

other point locations provided on the Point select menu.


116


Tip: More Help:


• Topology

• The Viewing Menu (Ch. 7) in the Patran Reference Manual

Point Project Method With Normal to Surf Option Example

Creates Points 21 through 28, using the Create/Project/Normal to Surf option. Points 13:16, 18:20 and

Node 1 are all projected normally onto Surface 1. Notice Delete Original Points is pressed in.


118

Point Project Method With Define Vector Option Example

Creates Points 21 through 28, using the Create/Point/Project/Define Vector option. The points are

projected onto Surface 1 through the vector <-1 0 1> that is expressed within the Refer. Coordinate

Frame, Coord 1. Notice that Delete Original Points is pressed in.


Point Project Method With View Vector Option Example

Creates Points 21 through 28, using the Create/Project/View Vector option. The points are projected onto

Surface 1 using the view angle of the current viewport. Notice that Delete Original Points is pressed in

and Points 13 through 20 are deleted.


120

Creating Curves Between Points

Creating Curves Through 2 Points

The Point method using the 2 Point option creates straight parametric cubic curves between two existing

point locations. The point locations can be existing points, vertices, nodes, or other point locations

provided on the Point select menu.


Tip: More Help:


• Parametric Cubic Geometry

• PATRAN 2 Neutral File Support For Parametric Cubic Geometry

Curve Point Method With 2 Point Option Example

Creates Curve 3, using the Create/Point/2 Point option, which is between Point 1 and Node 10.


122


The Point method using the 3 Point option creates parametric cubic curves that pass through three

existing point locations where the starting point defines the curve at and the ending point defines

the curve at . The point locations can be existing points, vertices, nodes, or other point locations


ξ1

0Z

ξ1

1Z


124

Creates Curve 1, using the Create/Point/3 Point option, which is created through Points 1 and 2 and Node

10. Point 2 is located on the curve at x1(u) =0.5.


This example is the same as the previous example, except Point 2 is located on the curve at =0.75,

instead of 0.5.

ξ1u( )



The Point method using the 4 Point option creates parametric cubic curves that pass through four existing

point locations where the starting point defines the curve at and the ending point defines the curve

at . The point locations can be existing points, vertices, nodes, or other point locations provided

on the Point select menu.

ξ1

0Z

ξ1

1Z


126


Tip: More Help:




• Topology

• Connectivity



Creates Curve 1, using the Create/Point/4 Point option, which is created through Points 1, 2 and 3 and

Node 10. Point 2 is located at =0.333 and Point 3 is located at =0.667.ξ1u( ) ξ

1u( )


128


This example is the same as the previous example, except that Point 2 is located at x1(u) =0.25 and Point

3 is located at x1(u) =0.80.


Curve 4 Point Parametric Positions Subordinate Form

This subordinate form is displayed when the Parametric Positions button is pressed on the Geometry

Application’s Create/Curve/Point form for the 4 Point option.


130

Tip: More Help:


• Topology

• Connectivity


Creating Arced Curves (Arc3Point Method)

The Arc3Point method creates true arced curves that pass through three specified point locations. Patran

calculates the arc’s center point location and the radius and angle of the arc. The three point locations can

be points, vertices, nodes, or other point locations that are provided on the Point select menu.


Tip: More Help:




• Topology

• Matrix of Geometry Types Created

Curve Arc3Point Method Example

Creates Curve 3, using the Create/Arc3Point method, which creates a true arc through Points 1 through

3. Notice that Create Center Point is pressed which created Point 4.


132

Curve Arc3Point Method Example

This example is similar to the previous example, except that the point locations for the arc are specified

with point coordinate locations.


Creating Chained Curves

The Chain method creates a chained composite curve from one or more existing curves or edges. The

existing curves and edges must be connected end to end. If a chained curve is used to create planer or

general trimmed surfaces for an inner loop, they must form a closed loop. Chained curves are used to

create planar or general trimmed surfaces using the Create/Surface/Trimmed form.


134

Tip: More Help:


• Trimmed Surfaces

• Creating Trimmed Surfaces

• Disassembling a Chained Curve

Curve Chain Method Example

Creates Curve 11, using the Create/Chain method, which is created from Curves 3 through 10. Notice

that Delete Constituent Curves is pressed and Curves 3 through 10 are deleted.


Creating Conic Curves

The Conic method creates parametric cubic curves representing a conic section (that is, hyperbola,

parabola, ellipse, or circular arc), by specifying point locations for the starting and ending points of the

conic and the conic’s focal point. The point locations can be points, vertices, nodes or other point

locations provided on the Point select menu.


136


Curve Conic Method Example

Creates Curve 1, using the Create/Conic method whose focal point is Point 3, the starting and ending

points are Points 1 and 2, and the conic altitude is 0.50.


138

Curve Conic Method Example

This is the same as the previous example, except that the conic altitude is increased to 0.75 from 0.50 for

Curve 2.


Extracting Curves From Surfaces

Extracting Curves from Surfaces Using the Parametric Option

The Extract method creates curves on an existing set of surfaces or solid faces by specifying the surface’s

or face’s parametric or coordinate location where has a range of and has a range

of .

ξ1

ξ2

ξ1

0 ξ1

1≤ ≤ ξ2

0 ξ2

1≤ ≤


140

Curve Extract Method With the Parametric Option Example


Creates Curve 1, using the Create/Extract/Parametric option. The curve is created on Surface 2 at

= 0.75. Notice that the parametric direction is displayed.


This example is the same as the previous example, except that Curve X is created at = 0.75, instead

of = 0.75.

ξ2v( )

ξ1u( )

ξ2v( )


142


Creates Curve 3 which is at on a surface defined by Curve 2 and an edge of Surface 1 by

using the Surface select menu icons listed below.

ξ2v( ) 0.25Z


Extracting Curves From Surfaces Using the Edge Option

The Extract method creates curves on specified edges of existing surfaces or solid faces.


144

Tip: More Help:




• Topology


Curve Extract Method With Edge Option Example

Creates Curve 3, using the Create/Extract/Edge option. The curve is created on one of the edges of

Surface 1.


Creating Fillet Curves

The fillet method is intended for use with 2D construction. The created curve is a circular arc. For this

reason, the method will not work if the provided curves are not co-planar. The Patran 2.5 switch overrides

this requirement and places no restriction on coplanarity. The result is a single cubic line so that it is more

like a slope continuous blend between the 2 curves.


146


Tip: More Help:




• Topology

Curve Fillet Method Example

Creates Curve 3, using the Create/Fillet method. The fillet curve is created between Curve 1 and Point 4

and Curve 2 and Point 5, with a radius of 0.5. Notice Trim Original Curves is pressed.


148

Curve Fillet Method Example

Creates Curve 3, using the Create/Fillet method. The fillet curve is created between Curve 1 and Point 2

and Curve 2 and Point 3, with a radius of 0.25.


Fitting Curves Through a Set of Points

The Fit method creates a parametric cubic curve by fitting it through a set of two or more point locations.

Patran uses a parametric least squares numerical approximation for the fit. The point locations can be

points, vertices, nodes, or other point locations provided on the Point select menu.


150

Tip: More Help:




• Topology

Curve Fit Method Example

Creates three curves starting with Curve 1, using the Create/Fit method. The curve is created through

Points 1 through 6.


Creating Curves at Intersections

Creating Curves at the Intersection of Two Surfaces

The Intersect method using the 2 Surface option creates curves at the intersection of two surfaces or solid

faces. The two surfaces or faces must completely intersect each other.


152

Tip: More Help:




• Topology


Curve Intersect Method With 2 Surface Option Example

Creates Curve 1 using the Create/Intersect method with the 2 Surface option. The curve is located at the

intersection of Surfaces 1 and 2.



This example is similar to the previous example, except the second surface is instead defined by Curves

2 and 3 by using the Surface select menu icon and selecting Curves 2 and 3 to create Surface 2.


154


Creates Curve 1 using the Create/Intersect/2 Surface option. The curve is located at the intersection of

Surfaces 1 and 4.


Creating Curves at the Intersection of a Plane and a Surface

The Intersect method with the Plane-Surface option creates curves at the intersection of a defined plane

and a surface or a solid face. The plane and the surface or face must completely intersect each other.


156

Tip: More Help:




• Topology


Curve Intersect Method With Plane-Surface Option Example

Creates Curve 1 which is located at the intersection of Surface 1 and a plane whose normal is defined at

{[0 2.5 0][0 3.5 0]}.


Curve Intersect Method With the Plane-Surface Option Example

Creates Curve 1 which is located at the intersection of Surface 2 and a plane whose normal is defined by

the Z axis of Coord 1, Coord 1.3, by using the Axis select menu icon listed below.


158

Intersect Parameters Subordinate Form

The Intersect Parameters subordinate form appears when the Intersect Parameters button is pressed on

the Create/Curve/Intersect application form.


Tip: More Help:




Creating Curves at the Intersection of Two Planes

This form is used to create a curve from the intersection of two planes.


160

Tip: More Help:




• Topology


Creating Curve Intersect from Two Planes Example

Create curve 1 with a length of 0.334 from the intersection of plane 1 and 2.


Manifold Curves Onto a Surface

Manifold Curves onto a Surface with the 2 Point Option

The Manifold method with the 2 Point option creates curves directly on an existing set of surfaces or solid

faces by using two point locations on the surface. The point locations must lie on the surface or face. The

point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


162

Tip: More Help:





• Topology


Curve Manifold Method With the 2 Point Option Example

Creates three curves starting with Curve 1 using the Create/Manifold/2 Point option. The curves are

created on Surface 1 between Point 7 and Points 2,5 and 8.

Curve Manifold Method With the 2 Point Option On a Face Example

Creates Curve 1 using the Manifold/2 Point option on a face of Solid 1 that is between Points 5 and 12.


164

Manifold Curves onto a Surface With the N-Points Option

The Manifold/N-Points option creates curves directly on a set of surfaces or solid faces by using two or

more point locations on the surface. The point locations must lie on the surface or face and they can be

existing points, vertices, nodes or other point locations provided on the Point select menu.


Tip: More Help:




• Topology


Curve Manifold Method With N-Points Option Example

Creates Curve 1 using the Create/Manifold/N-Points option. The curve is created on Surface 1 through

Points 5, 8, 17, 18 and 4.


166

Curve Manifold Method With N-Points Option On a Face Example

Creates Curve 1 using the Create/Manifold/N-Points option. The curve is created on the top face of Solid

1, through Points 6, 12, 13 and 5.


Manifold Parameters Subordinate Form

The Manifold Parameters subordinate form appears when the PATRAN 2 Convention toggle is ON and

the Manifold Parameters button is pressed on the Create/Curve/Manifold application form.


168

Tip: More Help:




Creating Curves Normally Between a Point and a Curve (Normal Method)

The Normal method creates straight parametric cubic curves from a point location, normally to a curve

or an edge. The point location can be points, vertices, nodes, or other point locations provided on the

Point select menu.


Tip: More Help:




• Topology

Curve Normal Method Example

Creates Curve 6 using the Create/Normal method. The curve is created from Point 13 normally to the

edge of Curve 5.


170

Curve Normal Method From An Edge Example

Creates Curve 1 using the Create/Normal method. The curve is created from Point 20 normally to an edge

of Surface 4 by using the Curve select menu icon listed below.


Creating Offset Curves

Creating Constant Offset Curve

This form is used to create a constant offset curve.


172

Tip: More Help:


Creating Constant Offset Curve Example

Create offset curves 2 thru 4 by offsetting a distance of .5 from curve 1 using a repeat count of 3.


Creating Variable Offset Curve

This form is used to create a variable offset curve.


174

Tip: More Help:


Parameterization Control for Variable Offset Curve

This form is used to define the parameterization control for the offset curve. There are two types; Arc

Length and Parameter Value.


Creating Variable Offset Curve Example

Create curves 2 thru 3 from curve 1 by offsetting a start distance of .25 and an end distance of 1. Use

parameter values of .5 and 1.0.


176

Projecting Curves Onto Surfaces

The Project method creates curves by projecting a set of curves or edges along a defined projection

vector, onto a surface or solid face.


Available options are:

Normal to Plane - The curves or edges in Curve List will be projected through a vector that is normal to

at least one of the curves or edges that define a plane.

Normal to Surf - The curves or edges in Curve List will be projected through a vector that is normal to

the surface or solid face specified in Surface List.

Define Vector - The project direction is defined by the vector coordinates entered in the Projection

Vector databox which is expressed within the Refer. Coordinate Frame. Example: <1 1 0>. The Vector

Select menu will appear to allow you alternate ways to cursor define the vector definition.

View Factor - The project direction is defined by the view angle in the current viewport. Patran will

project the existing points using the normal direction of the screen.


178

Tip: More Help:




• Topology


• The Viewing Menu (Ch. 7) in the Patran Reference Manual

Curve Project Method With the Normal to Plane Option Example

Creates Curve 7 using the Create Project/Normal to Plane option. The curve is projected from Curve 6

onto Surface 2 that is normal to the plane defined by Curve 6.


Curve Project Method With the Normal to Surf Option Example

Creates Curve 8 using the Create/Project/Normal to Surf option. The curve is projected from Curve 6

normally onto Surface 2. Notice that Delete Original Curves is pressed and Curve 6 is deleted.


180

Curve Project Method With Define Vector Option Example

Creates Curve 7 with the Define Vector option. The curve is projected from Curve 6 onto Surface 2

through the vector that is defined by Points 19 and 20 by using the Vector select menu icon listed below.


Curve Project Method With View Vector Option Example

Creates Curve 7 with the View Vector option. The curve is projected from Curve 6 onto Surface 2

through the view angle of the current viewport. Notice that Delete Original Curves is pressed and Curve

6 is deleted.


182

Project Parameters Subordinate Form

The Project Parameters subordinate form appears when the Project Parameters button is pressed on the

Create/Curve/Project application form.


Tip: More Help:




Creating Piecewise Linear Curves

The PWL method will create a set of piecewise linear (or straight) parametric cubic curves between a set

of existing point locations. The point locations can be points, vertices, nodes or other point locations



184

More Help:




• Topology

Curve PWL Method Example

Creates seven curves starting with Curve 5 using the Create/PWL method. The straight curves are created

through Points 12 through 18 and Node 1.


Creating Spline Curves

Creating Spline Curves with the Loft Spline Option

The Spline method using the Loft Spline option creates piecewise cubic polynomial spline curves that

pass through at least three point locations. Patran processes the slope continually between the point

segments. The point locations can be points, vertices, nodes or other point locations provided on the Point

select menu.


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Curve Spline Method With Loft Spline Option Example

Creates Curve 1 using the Create/Spline method with the Loft Spline option. The curve is created through

Points 1 through 5. Notice that since End Point Slope Control are not pressed in, Start and End Point

Tangent Vector are disabled.


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Curve Spline Method With Loft Spline Option Example

This example is the same as the previous example, except that Curve 2 is created with End Point Slope

Control is pressed in. The Start Point Tangent Vector is defined by Points 1 and 2, and the End Point

Tangent Vector is defined by Points 4 and 5, using the Vector select menu icon listed below.


Creating Spline Curves with the B-Spline Option

The Spline/B-Spline option creates spline curves that pass through at least three point locations. Patran

processes the slope continually between the point segments. The point locations can be points, vertices,

nodes or other point locations provided on the Point select menu.


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Curve Spline Method With B-Spline Option Example

Creates Curve 1 with the B-Spline option. The B-spline has an order of 3 and uses Points 1 through 5.

Since Interpolation is not pressed, the curve is not forced to pass through all the points.


This example is the same as the previous example, except that the order for Curve 2 is three, instead of

five.


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This example is the same as the previous example, except Interpolation is pressed and Curve 3 is forced

to pass through Points 1 through 5.


Creating Curves Tangent Between Two Curves (TanCurve Method)

The TanCurve method creates straight parametric cubic curves that are tangent between two existing

curves or edges. The curves or edges cannot be straight, or else Patran will not be able to find the tangent

location on each curve.


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Curve TanCurve Method Example

Creates Curve 10 using the Create/TanCurve method. The curve is tangent between Curves 9 and 8 with

Points 26 and 25 as the endpoints selected in the Point 1 and 2 Lists. Notice that Trim Original Curves is

pressed.


Creating Curves Tangent Between Curves and Points (TanPoint Method)

The TanPoint method creates straight parametric cubic curves that are tangent between a point location

and a curve or an edge. The curve or edge cannot be straight, or else Patran will not be able to find the

tangent location. The point locations can be points, vertices, nodes or other point locations provided on

the Point select menu.


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Curve TanPoint Method Example

Creates Curve 10 using the Create/TanPoint method. The curve is tangent between Point 25 and Curve

9. Notice that Trim Original Curves is pressed in and Curve 9 is trimmed.


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Curve TanPoint Method Example

Creates Curve 1 using the Create/TanPoint method. The curve is tangent between Point 9 and an edge of

Surface 1.


Creating Curves, Surfaces and Solids Through a Vector Length (XYZ Method)

The XYZ method creates parametric cubic curves, surface, or solids from a specified vector length and

origin. The origin can be expressed by cartesian coordinates or by an existing vertex, node or other point

location provided by the Point select menu.


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Curve XYZ Method Example

Creates Curve 3 using the Create/XYZ method, whose origin is located at Point 6 and whose vector

orientation and length is <20 10 0>.


Surface XYZ Method Example

Creates Surface 3 using the Create/XYZ method, whose origin is located at Point 6 and whose vector

orientation and length is <20 10 5>.


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Solid XYZ Method Example

Creates Solid 1 whose origin is located at Point 6 and whose vector orientation and length is <20 10 5>

which is expressed within the Reference Coordinate Frame, Coord 0.


Creating Involute Curves

Creating Involute Curves with the Angles Option

The Involute/Angles option creates parametric cubic curves from a point location. The point location can

be a point, vertex, node or other point locations provided on the Point select menu. Involute curves are

like the unwinding of an imaginary string from a circular bobbin. Intended for gear designers, the Angles

option requires the angle of the unwinding and the starting angle.


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Curve Involute Method With the Angles Option Example

Creates four curves starting with Curve 5 using the Create/Involute/Angles option, where the curve is

unwound 360 degrees about the involute axis {[0 0 0][0 0 1]}, from Point 13.


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Creating Involute Curves with the Radii Option

The Involute/Radii option creates parametric cubic curves from a point location. The point location can

be a point, vertex, node or other point location provided on the Point select menu. Involute curves are

like the unwinding of an imaginary string from a circular bobbin. Intended for the material modeling

community, the Radii option requires the base radius of the bobbin and the radius of the stop of the curve.


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Curve Involute Method With the Radii Option Example

Creates six curves starting with Curve 5 using the Create/Involute/Radii option, where the curve is

unwound starting with a base radius of 0.1 and a stop radius of 2, about the involute axis {[0 0 0][0 0 1]},

starting from Point 13.


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Revolving Curves, Surfaces and Solids

The Revolve method creates curves, surfaces or solids by the rotation of a point, curve or surface

location, respectively. The new geometric entity is rotated about a defined axis. Point locations can be

points, vertices, or nodes, Curve locations can be curves or edges. Surface locations can be surfaces or

solid faces.


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Curve Revolve Method Example

Creates Curves 5 and 6 using the Create/Revolve method, where the curves are created from Points 12

and 13 about the axis, {[0 0 0][0 0 1]} for 180 degrees, with an offset of 30 degrees.


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Surface Revolve Method Example

Creates Surface 1 where the surface is created from a curve defined by Points 1 and 2 using the Curve

select menu icon listed below. The surface is revolved 45 degrees about the axis {Point 1 [x1 y1 1]}.


Surface Revolve Method Example

Creates four surfaces starting with Surface 2 using the Create/Revolve method, where the surfaces are

created from Curves 9 through 12 about the axis, {[0 0 0 ] [ 1 0 0 ]} for 360 degrees.


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Solid Revolve Method

Creates Solid 1 using the Create/Revolve method, where the solid is created from Surface 2. The axis is

defined by the Points 15 and 12 using the Axis select menu icon listed below, for a rotation of 90 degrees.


Solid Revolve Method

Creates Solid 1 using the Create/Revolve method, where the solid is created from Surface 1 about the X

axis of Coord 1 (by using the Axis select menu listed below) for 90 degrees.


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Creating Orthogonal Curves (2D Normal Method)

Creating Orthogonal Curves with the Input Length Option

The 2D Normal/Input Length option creates straight parametric cubic curves that lie on a defined 2D

plane and is perpendicular to a curve or an edge. The curve is defined from a specified point location.

The point location can be a point, vertex, node or other point locations provided on the Point select menu.


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Curve 2D Normal Method With the Input Length Option

Creates Curve 1 with the Input Length option, where the curve is 1 unit long; it lies within the plane

whose normal is the Z axis of Coord 3; it is perpendicular to the top edge of Surface 1; and its starting

point is near Point 3.


Curve 2D Normal Method With the Input Length Option

This example is the same as the previous example, except that Flip Curve Direction is pressed.


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Creating Orthogonal Curves with the Calculate Length Option

The 2D Normal/Calculate Length option, creates straight parametric cubic curves that lie on a defined

2D plane and is perpendicular to an existing curve or edge. The curve is defined from specified point

location. The point location can be a point, vertex, node or other point locations provided on the Point

select menu.


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Curve 2D Normal Method With the Input Length Option Example

Creates Curve 1 with the Input Length option. The distance of Curve 1 is 1.0; it lies within the plane

whose normal is the global coordinate frame’s X axis, Coord 0.1; and it is starts from a point that is

closest to Point 6.


Curve 2D Normal Method With the Calculate Length Option Example

Creates Curve 1 with the Calculate Length option. The distance of Curve 1 is the distance between Points

3 and 4; it lies within the plane whose normal is the Z axis of Coord 3; and it starts from a point that is

closest to Point 3.


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Creating 2D Circle Curves

The 2D Circle method creates circular curves of a specified radius that is within a defined 2D plane, based

on a center point location. The point location can be a point, vertex, node or other point locations



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Curve 2D Circle Method With the Input Radius Option Example

Creates Curve 5 using the Create/2D Circle method with the Input Radius option, where the circle has a

radius of 1.0, its center point is at Node 1, and it lies within the plane whose normal is the Z axis of Coord

0.


Curve 2D Circle Method With the Calculate Radius Option Example

Creates Curve 5 using the Create/2D Circle/Calculate Radius option, where the radius is measured from

Point 12 to Node 1, its center point is at Node 1, and it lies within the plane whose normal is the Z axis

of the global rectangular coordinate frame, Coord 0.


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Creating 2D ArcAngle Curves

The 2D ArcAngles method creates arced curves within a defined 2D plane. The Arc parameter inputs are

Radius, Start Angle and End Angle. The point location for the arc’s center is to be input.


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Curve 2D ArcAngle Method Example

Creates Curve 1 using Create/Curve/2D ArcAngles.


Creating Arced Curves in a Plane (2D Arc2Point Method)

Creating Arced Curves with the Center Option

The 2D Arc2Point method creates arced curves within a defined 2D plane. Two options are provided.

The Center option inputs are point locations for the arc’s center and the arc’s starting and ending points.

The Radius option inputs are the radius and point locations for the arc’s starting and ending points.


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Curve 2D Arc2Point Method With Center Min. Angle Option Example

Creates Curve 5 using the Create/2D Arc2Point method, where the Minimum Angle is chosen; the arced

curve is between Point 13 and Node 1; its center point is Point 12; and the curve lies within the plane

whose normal is {[0 0 0][0 0 1]}.


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Curve 2D Arc2Point Method With Center Max. Angle Option Example

Creates Curve 5 using the Create/2D Arc2Point method, where the Maximum Angle is chosen; the arced

curve is between Point 13 and Node 1; its center point is Point 12; and the curve lies within the plane

whose normal is {[0 0 0][0 0 1]}.


Creating Arced Curves with the Radius Option

The 2D Arc2Point method creates arced curves within a defined 2D plane. Two options are provided.

The Center option inputs are point locations for the arc’s center and the arc’s starting and ending points.

The Radius option inputs are the radius and point locations for the arc’s starting and ending points.


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Curve 2D Arc2Point Method with Radius Option Example

Creates Curve 1 by creating an arc with a radius of 1.5 using [-1 -.5 -1] and [1 1 1] as start/end points and

in the Z construction plane.


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Arc2Point Parameters Subordinate Form

The Arc2Point Parameters subordinate form appears when the Arc2Point Parameters button is pressed

on the Create/Curve 2D Arc2Point application form.


Creating Arced Curves in a Plane (2D Arc3Point Method)

The 2D Arc3Point method creates arced curves within a defined 2D plane, based on point locations for

the arc’s starting, middle and ending points. The point locations can be points, vertices, nodes or other

point locations provided on the Point select menu.


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Curve 2D Arc3Point Method Example

Creates Curve 5 using the Create/2D Arc3Point method. The arced curve is created through the Points

13, 14 and Node 1 and it lies within the plane whose normal is {[0 0 0][0 0 1]}. Notice that Create Center

Point is pressed in and Point 16 is created.


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Creating Surfaces from Curves

Creating Surfaces Between 2 Curves

The Curve method using the 2 Curve option creates surfaces between two curves or edges. Degenerate

three-sided surfaces can be created. See Building a Degenerate Surface (Triangle) for more information.


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Surface Curve Method With the 2 Curve Option Example

Creates Surface 2 using the Create/Curve/2 Curve option. The curve is created between Curves 5 and 6.


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Surface Curve Method With the 2 Curve Option Example

Creates Surface 2 that is degenerate with the 2 Curve option which is between an edge of Surface 1 and

a zero length curve defined by Point 5, twice.


Creating Surfaces Through 3 Curves (Curve Method)

The Curve method using the 3 Curve option creates surfaces that pass through three existing curves or

edges.


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Surface Curve Method With 3 Curve Option Example

Creates Surface 2 using the Create/Curve/Curve option. The curve is created through Curves 5, 6 and 8.



Creates Surface 2 through Curves 2, 3 and an edge of Surface 1.


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Creating Surfaces Through 4 Curves (Curve Method)

The Curve method using the 4 Curve option creates surfaces that pass through four existing curves or

edges.


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Creates Surface 3 using the Create/Curve/4 Curve option. The curve is created through Curves 5,6 and 8

and the edge of Surface 2 by using the Curve select menu icon listed below.


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Creating Surfaces from N Curves (Curve Method)

The Curve method using the N-Curves option creates surfaces that pass through any number of curves or

edges.


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Surface Curve Method With N-Curves Option Example

Creates Surface 2 using the Create/Curve/N-Curves option. The curve is created through Curves 5,6,8,9

and 10.


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Creating Composite Surfaces


Figure 4-1 The Composite method creates surfaces composed from multiple surfaces.

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General Comments

If valid boundary loops are identified and any of the vertices in the vertex list are not part of a boundary,

the location will be marked red and the user will be prompted to “ignore and continue” or “stop”.

The Surface Builder always computes the optimal view plane based on the Surface List. In most cases

this is satisfactory; however, in some instances, it can create a very distorted parametrization of the new

surface, leading to poor finite element mesh quality. Sometimes the view selected by the user as “best”

is more successful than the recommended optimal plane (i.e., answer “No” to the prompt asking

permission to reorient the model to a better view); otherwise, the proposed Composite Surface will have

to be represented by multiple composite surfaces.

If the Composite Surface Builder often fails because of unresolved boundary edges, the gap and clean-

up tolerances are most likely too small. If edges disappear the tolerances are probably too large. The

default gap and clean-up tolerances are set equal to the global model tolerance and can be changed on the

Options form.


Composite Surface Options

Surface Composite Method Example

Creates Surface 2 from the surfaces in the viewport.


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Decomposing Trimmed Surfaces

The Decompose method creates four sided surfaces from an existing surface or solid face by choosing

four vertex locations. This method is usually used to create surfaces from a multi-sided trimmed surface

so that you can either mesh with IsoMesh or continue to build a tri-parametric solid.

See Decomposing Trimmed Surfaces for more information on how to use the Decompose method.


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Surface Decompose Method Example

Creates Surfaces 3, 4 and 5 using the Create/Decompose method. The surfaces are created from Trimmed

Surface 2 and they are defined by the cursor selected vertices listed in the Surface Vertex databoxes on

the form.


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Creating Surfaces from Edges (Edge Method)

The Edge method creates three or four sided surfaces that are bounded by three or four intersecting curves

or edges, without manifolding the surface to an existing surface or face.


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• Surface Edge Method With the 3 Edge Option Example

Creates Surface 3 using the Create/Edge/3 Edge option. The degenerate surface is created from Curves

5 and 6 and the edge of Surface 2. See Building a Degenerate Surface (Triangle).


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Surface Edge Method With the 4 Edge Option Example

Creates Surface2 using the Create/Edge/4 Edge option. The surface is created from Curves 5 through 8.


Extracting Surfaces

Extracting Surfaces with the Parametric Option

The Extract method creates surfaces by creating them from within or on a solid, at a constant parametric

, , or coordinate location, where has a range of , has a range of ,

and has a range of . One surface is extracted from each solid.

ξ1u( ) ξ

2v( ) ξ

3w( ) ξ

10 ξ

11≤ ≤ ξ

20 ξ

21≤ ≤

ξ3

0 ξ3

1≤ ≤


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• Parametric Cubic Geometry, 25


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• Connectivity


Surface Extract Method With the Parametric Option Example

Creates Surface 2 using the Create/Extract/Parametric option. The surface is created at

within Solid 1. Notice the parametric direction is displayed near Point 19.

ξ3w( ) 0.75Z


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Surface Extract Method With the Parametric Option Example

Creates Surface 3 using the Create/Extract/Parametric option. The surface is created at

within a solid that is defined by Surfaces 1 and 2 by using the Solid select menu icons listed below.

ξ3w( ) 0.75Z


Extracting Surfaces with the Face Option

The Extract method creates surfaces by creating them on a specified solid face. One surface is extracted

from each solid face.


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Surface Extract Method With the Face Option Example

Creates Surfaces 2 and 3 using the Create/Extract/Face option. The surface is created on two faces of

Solid 10.


Creating Fillet Surfaces

The Fillet method creates a parametric bi-cubic surface between two existing surfaces or solid faces. The

existing surfaces or faces do not need to intersect. If they do intersect, the edges of the surfaces or faces

must be aligned, and they must intersect so that a nondegenerate fillet can be created.


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Surface Fillet Method Example

Creates Surface 4 using the Create/Fillet method that is between Surfaces 1 and 3 with the fillet’s

endpoints, Points 2 and 10, cursor selected. Surface 4 has a varying fillet radius of 0.25 to 0.5.


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Surface Fillet Method Example

Creates Surface 5 using the Create/Fillet method that is between Surfaces 3 and 4 with the fillet’s

endpoints, Points 19 and 25, cursor selected. Surface 5 has a constant fillet radius of 0.75.


Matching Adjacent Surfaces

The Match method creates parametric bi-cubic surfaces with common boundaries (or matched edges)

from a pair of topologically incongruent surfaces or solid faces that have two consecutive common

vertices but unmatched edges. The surface pair need not have matching parametric orientations. Patran

requires geometry to be topologically congruent for IsoMesh and Paver to create coincident nodes at the

common boundaries. See Topological Congruency and Meshing for more information.

You can also match incongruent surfaces with the Edit action’s Edge Match method. See Matching

Surface Edges for more information.


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• Meshing Surfaces with IsoMesh or Paver (p. 13) in the Reference Manual - Part III

Surface Match Method Example

Creates Surface 4 using the Create/Match method that is topologically congruent with Surface 2. Notice

that Delete Original Surfaces is pressed in and Surface 3 is deleted.


Creating Constant Offset Surface

This form is used to create a constant offset surface.


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Creating Constant Offset Surface Example

Create surfaces 2 and 3 by offsetting from surface 1, a distance of 0.5 with a repeat count of 2 and

reversing the direction vector of surface 1.


Creating Ruled Surfaces

The Ruled method creates ruled surfaces between a pair of curves or edges.


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Surface Ruled Method Example

Creates Surface 1 using the Create/Ruled method which is created between Curves 1 and 2.


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Surface Ruled Method Example

Creates Surface 3 using the Create/Ruled method which is created between Curve 5 and an edge of

Surface 2 by using the Curve select menu icon listed below. Notice that since Equal Parametric Values

was pressed in, Surface 3’s parametric direction is the same as for Curve 5.ξ1


Creating Trimmed Surfaces

The Trimmed method creates a trimmed surface. You must first create at least one chained curve for the

surface’s outer loop or boundary by using the Create/ Curve/Chain form before using this form, or by

bringing up the Auto Chain form from within this form. (Note that an outer loop must be specified, and

the inner loop being specified is not necessary.) Trimmed surfaces can be meshed by Paver.


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• Creating Chained Curves


Creating Trimmed Surfaces with the Surface Option

Creates Surface 3 using the Create/Surface/Trimmed/Surface option which is created from chained

Curve 22 for the outer loop, chained Curve 21 for the inner loop and Surface 2 for the parent surface.

Notice that Delete Outer and Inner Loop and Delete Constituent Surface are pressed in and Curves 21

and 22 and Surface 2 are deleted.


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Creating Trimmed Surfaces with the Planar Option

Creates Surface 2 using the Create/Surface/Trimmed/Planar option which is created from chained Curve

14 for the outer loop and chained Curve 13 for the inner loop. Notice that Delete Outer Loop and Delete

Inner Loop are pressed in and Curves 13 and 14 are deleted.


Auto Chain Subordinate Form

The Auto Chain form provides a more interactive, user-controllable way of creating Chain Curves. A

start curve is selected for the chain and then during the creation of the chain, if necessary, the user will

be prompted to make decisions on how to proceed by selecting the appropriate buttons. Toggles are

provided for additional control of the chain curve creation. This subordinate form is accessible from

either the Create/Curve/Chain or the Create/Surface/Trimmed forms.


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Creating Trimmed Surfaces with the Composite Option

The Create/Surface/Trimmed/Composite option provides a tool for combining surfaces into a single

trimmed surface, where the parent trimmed surfaces may have gaps or overlaps of a specified distance,

and are not required to be topologically congruent. Though the constituent surfaces are used for all

evaluations without any approximation, the resulting composite surface is seen as a single trimmed

surface by all operations that reference it, such as the Paver.

Shadow Surface Method

The method used to create a composite trimmed surface is called a Shadow Surface Method. The best

way to describe a shadow surface is to use a real life analogy. Consider a cloud in the sky to be a shadow

surface. Then the sun, being the light source behind the cloud, creates a shadow on the planet Earth, only

Next: Used to update the "Choose Curve to

Continue" databox when multiple

choices are possible, i.e. a branch.

OK: Used to finalize the selection on the

curve echoed in the "Choose Curve

to Continue" databox and continue

the auto chain process.

Previous: Used to update "Choose Curve to

Continue" databox when more than two

curves form a branch. Use in

conjunction with the Next button.

Quit: Used to end the auto chain process

without attempting to creating a

chain.

Backup: Used to backup one curve at a time in

the list of curves that have been

previously selected as constituents for

the resulting chain.

Stop: Used to end the auto chain process

and attempt to create a chain from

the constituent curves. (Only

necessary when pressing the Apply

button did not create a chain.)

Delete: Used to delete the curve in the "Choose

Curve to Continue" databox from the

database.

Break: Used to break the curve in the

"Choose Curve to Continue"

databox.


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in the area blocked by the cloud. The same is true of the shadow surface, except a view vector is used to

determine the light direction. The shadow itself is called an Under Surface, whose valid region is

defined by where the outlines of the shadow surface appear with respect to a given view.

The Shadow Surface itself is a collection of specified surfaces, which may have gaps or overlaps of a

specified distance, and may or may not be topologically congruent. It is bounded by outer and inner

loops, defined as closed chains of curves or surface edges.

During surface evaluations, the Under Surface is used to classify the point relative to which constituent

surface (amongst the Shadow Surface) contains it. The point is mapped to the parameter space of that

constituent surface, and the evaluation is done directly on that surface.

Creating Composite Surfaces

The steps in creating composite surfaces are, for the most part, the same as those for creating a normal

trimmed surface, with the following exceptions:

• More than one surface is specified to define the curvature (multiple parent surfaces).

• A Gap Distance parameter must be specified to define the maximum length for gaps or

overlaps.

• An appropriate view must be obtained, satisfying the following:

• Double Intersections between the Shadow Surface and the view vector must not occur. In other

words, the Shadow Surface must not wrap around on itself relative to the current view. This is

because the Under Surface is flat, and there is not necessarily a one-to-one mapping from the

Shadow Surface to the Under Surface. Surfaces that combine to create a cylinder, therefore,

cannot be used to create a single composite surface.

• No Dead Space. Unpredictable results will occur if any portion of the Shadow Surface does not

have an Under Surface counterpart. An example of dead space would be an area on the Shadow

Surface which runs parallel to the view vector. Since this portion has no area with respect to its

projection onto the Under Surface, it will not be represented properly in the resulting composite

surface. This can cause unwanted holes or spikes in the geometry.


Surface Trimmed Method - Composite Option Example

Creates Surface 5 using the Create/Surface/Trimmed/Composite option which is created from chained

Curve 5 for the outer loop, chained Curve 4 for the inner loop and Surface 1:4 for the parent surface.

Notice that Delete Outer and Inner Loop and Delete Constituent Surface are pressed in and Curves 1 and

2 and Surfaces 1:4 are deleted.


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Creating Surfaces From Vertices (Vertex Method)

The Vertex method creates four sided surfaces from four existing point locations that define the surface’s

vertices or corners. The point locations can be points, vertices, nodes or other point locations provided

on the Point select menu.


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Surface Vertex Method Example

Creates Surface 2 using the Create/Vertex method which is created from Points 12, 13, 14 and Node 1.

Notice that since Manifold is not on, the Manifold Surface databox is disabled.


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Extruding Surfaces and Solids

The Extrude method creates surfaces or solids by moving a curve or edge, or a surface or solid face,

respectively, through space along a defined axis with the option of scaling and rotating simultaneously.

This method is convenient for adding depth to a cross section, or for more complex constructions that

require the full capabilities of this form.


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Surface Extrude Method Example

Creates Surface 2 using the Create/Extrude method which is created from Curve 5. The surface is

extruded +10 units in the global Y direction.


Surface Extrude Method Example

This example is the same as the previous example, except that Surface 1 is extruded +10 units in the

global Y direction about an angle of 90 degrees and with a scale factor of 2. The origin of the scale and

rotation is at Point 14.


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Solid Extrude Method Example

Creates Solid 2 using the Create/Extrude method which is created from a face of Solid 1. The solid is

extruded +10 units in the global Y direction, with a scale factor of 2. The origin of the scale is at Point 21.


Gliding Surfaces

Gliding Surfaces with the 1 Director Curve Option

The Glide method creates biparametric surfaces by sweeping base curve along a path defined by a set of

director curves or edges.


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• Gliding Surfaces with the 2 Director Curve Option

Surface Glide Method - 1 Director Curve Example

Creates Surfaces 2 through 4 using the Create/Glide method which is created from Curve 10 for the

Director Curve and Curves 11, 13 and 14 for the Base Curves. The scale is set to 1.0 and Fixed Glide is

pressed in.


Gliding Surfaces with the 2 Director Curve Option

This option sweeps a base curve along a path defined by a pair of director curves. Automatic scaling is

optional.


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Surface Glide Method - 2 Director Curve Example

Creates Surface 1 by using Curves 1 and 2 as the director curves and Curve 3 as the base curve to glide

along.


Creating Surfaces and Solids Using the Normal Method

The Normal method creates parametric bi-cubic surfaces or solids which are defined by a set of base

curves or surfaces, respectively, and an offset distance from those curves or surfaces in the direction of

the curvature. The offset may be constant or have a varying thickness.


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Surface Normal Method Example

Creates Surface 2 using the Create/Normal method which is created from Curve 5. It has a varying

thickness of 0.75 at and x2=0 and a thickness of 2.0 at x1=0 and x2=1. Notice that the parametric

direction is on.

ξ1

0Z


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Surface Normal Method Example

Creates Surface 2 which is created from an edge of Surface 1. It has a constant thickness of 0.25 and the

normal direction is defined by a construction point, Point 9. Notice that the normal direction is measured

from the first vertex of the edge (Point 5) to Point 9.


Solid Normal Method Example

Creates Solid 1 using the Create/Normal method which is created from Surface 1 and has a thickness of

0.5. Notice that since PATRAN 2 Convention is not pressed in, the Solids per Surface databox is

disabled.


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This example is similar to the previous example, except that the thickness is -0.5 instead of +0.5.


Solid Normal Method From a Face Example

Creates Solid 2 using the Create/Normal method which is created from a face of Solid 1 and has a

thickness of 0.25.


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Creating Surfaces from a Surface Mesh (Mesh Method)

The Mesh method creates a surface from a congruent 2-D mesh. Vertices can be defined on the surface

boundary by selecting nodes in the Outer Corner Nodes or Additional Vertex Nodes listboxes.

Every edge of the surface will have at least one node. If no node is selected to identify a vertex, then one

will be selected automatically. The nodes entered in the Outer Corner Node listbox will define the

parametrization of the surface and will also be a vertex. If no nodes are selected, 4 appropriate nodes will

be selected automatically. Also the 4 nodes selected should be on the outer loop. Additional vertices can

be defined by selecting nodes in the Additional Vertex Nodes listbox.

The longest free edge loop will be the outer loop of the surface. The holes inside the mesh can be

preserved or closed by invoking the options in the Inner Loop Options pull-down menu. When few of the

inner holes need to be preserved Inner Loop Options is set to Select. Identify the holes by selecting at


least 1 node on the hole. If selected, nodes on the outer loop and those not on the free boundary, will be

ignored.

The parametrization of the surface can also be improved by setting Surface Creation Methods to Better

Parametrization. However, if speed were important and the mesh used to create the surface is of poor

quality, selecting the Fast option under the Surface Creation Methods pull-down menu would create a

better surface.

Tessellated Surface is a representation of the underlying mesh that is used to create it. Therefore the

surface is piecewise planar and the normals are not continuous. The surface is primarily generated to

facilitate the meshing operation on complex surface models. Though these surfaces support most of the

geometry operations, it has limitations due to the nature of the surface.

To create a tessellated surface the mesh should have the following characteristics:

• Congruent 2-D elements

• Should be one connected set of elements

• No more than 2 elements should share the same 2 nodes

• The outer or inner loop should not intersect.


306

Created Tessellated Surface from Geometry Form

Figure 4-2

Creating Midsurfaces

Creating Midsurfaces with the Automatic Option

This form is used to create a Midsurface using the Automatic Method.

Note: When the Inner Loop Options is set to Select, a node listbox opens. Here the holes to be

preserved can be identified by the nodes on its edge. Any nodes not on the hole edge or on

the outer boundary will be ignored.


Tip: More Help:


Create Midsurface Automatic Example

Create surfaces 1t6 by automatically computing the midsurfaces of solid 1 where the solid wall thickness

is less than 8.1.


308

Creating Midsurfaces with the Manual Option

This form is used to create a Midsurface using the Manual Method. The resulting midsurface will be

trimmed to the domain of the parent surface pairs.


More Help:


Create Midsurface Manual Example

Create surfaces 1t3 by manually selecting solid faces Solid 1.5 and Solid 1.9, Solid 1.4 and Solid 1.8,

Solid 1.7 and Solid 1.10 as face pairs to create the midsurfaces from.


310

311Chapter 4: Create ActionsCreating Solid Primitives

Creating Solid Primitives

Creating a Solid Block

This form is used to create a solid block with user input a point, length, width, height, and reference

coordinate frame. It also provides an option to perform boolean operation with the input target solid using

the created block as the tool solid.

Tip: More Help:


Geometry Modeling - Reference Manual Part 2Creating Solid Primitives

312

Creates solid blocks 1 and 2 at [0 0 0] and [2 0 0] with parameters of X=1.0, Y=1.0, Z=1.0 and X=2.0,

Y=2.0, Z=2.0 respectively.

Creates solid block 1 at [-1 .5 .5] with parameters of X=5.0, Y=1.0, Z=1.0 while performing a boolean

add operation with solid 1.


Creating Solid Cylinder

This form is used to create a solid cylinder with user input a point, height, radius, optional thickness, and

optional reference coordinate frame. It also provides an option to perform boolean operation with the

input target solid using the created cylinder as the tool solid.


314

Tip: More Help:


Creates solid cylinder 1 at point 1with parameters of Height=3.0, Radius=0.25, along X axis.


Creates Solid Cylinder 1 at point 1 with parameters Height=3.0, Radius=0.25, a wall thickness = 0.125

along X axis while performing a boolean add operation with solid 1.


316

Creating Solid Sphere

This form is used to create a solid sphere with user input a point, radius, and optional reference coordinate

frame. It also provides an option to perform boolean operation with the input target solid using the created

sphere as the tool solid.


Tip: More Help:


Creates Solid Sphere 1 at [0 0 0] with a Radius of 1.0 along the Z axis.


318

Creates Solid Sphere 1 at point 1with a Radius of 0.5 along the Y axis while performing a boolean add

operation with solid 1.


Creating Solid Cone

This form is used to create a solid cone with user input a point, base radius, top radius, height, optional

thickness, and optional reference coordinate frame. It also provides an option to perform boolean

operation with the input target solid using the created cone as the tool solid.


320

More Help:


Creates Solid Cone 1 at [0 0 0] and Cone 2 at [3 0 0] along the Z axis with parameters Height=2.0, Base

Radius=1.0, Top Radius=0.5 and Thickness for Cone 1=0.0 and Thickness for Cone 2=0.125


Creates Solid Cones 1 and 2 at [.5 1 .5] along the Y axis with parameters Height=-5.0, Base Radius=0.25,

Top Radius=0.0625 while performing a boolean add operation with Solid 1 and 2.


322

Creating Solid Torus

This form is used to create a solid torus with user input a point, major radius, minor radius, and optional

reference coordinate frame. It also provides an option to perform boolean operation with the input target

solid using the created torus as the tool solid.


Tip: More Help:


Creates Solid Torus 1 and 2 at [0 0 0] with parameters Major Radius=1.0, Minor Radius=0.5 and Torus

1 along the X axis and Torus 2 along the Y axis.


324

Creates Solid Torus 1 at [0 0 0] along the Z axis with parameters Major Radius=1.0, Minor Radius=0.25

while performing a boolean add operation with Solid 1.


Solid Boolean operation during primitive creation

This form is used to perform a Solid boolean operation on an existing solid during the creation of a new

primitive solid. This is a child form of the parent Create,Solid,Primitive form.


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More Help:

• Topology

• Connectivity






Creating Solids from Surfaces (Surface Method)

Creating Solids from Two Surfaces

The Surface method with the 2 Surface option, creates solids between two surfaces or solid faces.

Solid Surface Method With 2 Surface Option Example

Creates Solid 1 using the Create/Surface/2 Surface option. The solid is created between Surfaces 2 and 3.


328


Creates Solid 1 using the Create/Surface/2 Surface option. The solid is created between Surface 2 and a

surface defined by Curves 5 and 6, using the Surface select menu icon listed below.


Creating Solids from Three Surfaces (Surface Method)

The Surface method with the 3 Surface option creates solids that pass through three existing surfaces or

solid faces.


330


More Help:


• Topology






Creates Solid 2 using the Create/Surface/3 Surface option. The solid is created between a face of Solid

1, Surface 2 and a surface defined by Curves 5 and 6 by using the Surface select menu icon listed below.


332

Creating Solids from Four Surfaces (Surface Method)

The Surface method using the 4 Surface option creates solids that pass through four existing surfaces or

solid faces.


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• Topology






Creates Solid 2 using the Create/Surface/4 Surface option. The solid is created between a face of Solid

1, Surface 2, a surface defined by Curves 5 and 6 and Surface 3.


Creating Solids with the N Surface Option

The Surface method using the N-Surfaces option creates solids that pass through any number of existing

surfaces or solid faces.


336

More Help:


• Topology





Solid Surface Method with N-Surfaces Option Example

Creates Solid1 using the Create/Surface/N-Surfaces option. The solid is created between Surfaces 2, 7,

8, 9 and 10.


Creating a Boundary Representation (B-rep) Solid

The B-rep method creates boundary represented solids by specifying a list of surfaces or solid faces that

form a closed topologically congruent volume. B-rep solids can only be meshed with Patran’s TetMesh.

For more information, see Gliding Solids, 347.


338

Tip: More Help:


• Topology

• B-rep Solid

• Building B-rep Solids

Solid B-rep Method Example

Creates Solid 1 using the Create/Solid/B-rep method which is created from Surfaces 2, 3, 4, and 8 through

14. Notice that since Delete Original Surfaces is pressed in, the surfaces are deleted.


Creating a Decomposed Solid

The Decompose method creates solids from two opposing solid faces by choosing four vertex locations

on each face and then a solid is created from the two decomposed faces.


340

Tip: More Help:


• Topology




Solid Decompose Method with Face 1 Option Example

Creates Solid 2 by selecting four points on solid face Solid 1.6 and four points on solid face Solid 1.5.


Solid Decompose Method with Face 2 Option Example

Creates Solid 2 by selecting four points on solid face Solid 1.6 and four points on solid face Solid 1.5.


342

Creating Solids from Faces

The Face method creates a solid from five or six surfaces or solid faces which define the solid’s exterior

faces. The surfaces or faces can be in any order and they can have any parametric orientation, but they

must define a valid exterior of a solid.


Tip: More Help:


• Topology




Solid Face Method With 6 Faces Example

Creates Solid 1 using the Create/Face method which is created from Surfaces 2 through 7. The option is

set to 6 Face.


344

Solid Face Method With 5 Faces Example

Creates Solid 1 using the Create/Face method which is created from Surfaces 1 through 5. The option is

set to 5 Face.


Creating Solids from Vertices (Vertex Method)

The Vertex method creates parametric tri-cubic solids by specifying a list of eight point locations that

represent the eight vertices of the new solid. The point locations can be points, vertices, nodes or other



346

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Solid Vertex Method Example

Creates Solid 2 using the Create/Vertex method which is created from Points 12 through 15 and Nodes

34, 44, 254 and 264.


Gliding Solids

The Glide method creates triparametric solids by sweeping a base surface curve along a path defined by

a set of director curves or edges.


348

Tip: More Help:


• Topology


Solid Glide Method Example

Creates Solid 1 using the Create/Glide method which is created from Curve 5 for the Director Curve and

Surface 2 for the Base Surface. The scale is set to 0.25 and Fixed Glide is pressed in.

Geometry Modeling - Reference Manual Part 2Feature Recognition (Pre-release)

350

Feature Recognition (Pre-release)

Feature Types

The Feature Recognition Tool support the following feature types:

• Circular Hole features.

• Transition features.

• Blends

• Chamfers

The Actions supported for features are: Recognize, Clear, Show, Delete, Edit

The Methods supported for features are: Automatic, Interactive

Feature Definition

The feature has the following attributes:

Name: string identifier, i.e., Hole 1

Parameters: the values defining the feature, i.e.,

• for holes the parameters are radius and depth

• for blends the parameters are radius1 and radius2

• for chamfers the parameters are height1 and height2

Id: the internal id used for storage

Label: the numeric value of the feature name; i.e., if the feature name is Hole 1, the label is 1.

Automatic Recognition

You select the solid list from which the features are to be recognized from the viewport and the

corresponding features for which recognition was called is recognized. In case of transition features

automatic recognition recognizes all the features with chaining.

Interactive Recognition

You can interactively pick the face (or edge for holes) list from the viewport and only those features

which contain the selected faces (or edges for holes) are recognized. Single or compound/chain features

can be recognized during interactive recognition.

Overview of the Feature Recognition Modules

The feature recognition technology integrated in Patran is centered around two modules:

351Chapter 4: Create ActionsFeature Recognition (Pre-release)

Hole module. This module provides recognition of hole features in the input model. It

recognizes circular features. It can recognize circular holes which may be blind or thru. Non-

circular features like the rectangular holes, cannot be recognized with this module. Every hole

feature has two associated attributes namely the radius, and depth. In case of blind holes both

these attributes can be modified/edited, but in case of a thru hole only its radius can be

modified/edited. During recognition phase the dependency relations between different hole

features are also recognized. Subsequent operations on these features require satisfying these

dependency relations. For example, if hole 2 is dependent upon hole 1 (parent child relation)

then deletion of hole 1 will automatically result in deletion of hole 2. Similar relations apply for

editing of dependent features.

Blend/Chamfer module. This module provides recognitions of transition features namely blend

features and chamfer features. Two types of blends are recognized – constant radius blends and

variable radius blends. Thus each blend has two attributes namely the maximum radius and

minimum radius. However in case of constant radius blends the values of these two attributes are

same. Similarly a chamfer feature has two attributes which are its slope heights. Transition

features such as blends and chamfers are rarely isolated, and are usually connected to other

blends/chamfers to form a blend/chamfer chain. Thus automatic recognition by default

recognizes blends and chamfers with chaining, whereas, interactive recognition allows features

to be recognized as a single feature or a compound or chain feature. Figure below shows a blend

chain.


352

Limitations

Only one feature type per solid can be recognized and worked on at a time. For example, if you

have recognized holes from one solid, then recognize blends on the same solid in the same

Patran session, the feature modeler will replace the hole features with the newly recognized

blend features for the solid. You can recognize holes for one solid and blends for another solid

and the holes and blends will be stored in the feature modeler. All previous edits to the model by

editing hole parameters or deleting holes will be saved however.

Solids whose geometry source is Parasolid is the only type supported for Feature Recognition.

Feature Recognition

Recognize Feature Hole Automatic

Recognizes circular features from the selected Solid. It can recognize circular holes that are blind or

through. The dependency relations between different holes are also recognized.


Recognize Feature Hole Interactive

Recognizes circular features from the selected Solid Face or Edge . It can recognize circular holes that

are blind or through. The dependency relations between different holes are also recognized.


354

Recognize Feature Blend Automatic

Recognizes transition features such as Blend features from the selected Solid. It can recognize constant

radius and variable radius blends. The dependency relations between different blends are also

recognized. Automatic recognition by default recognizes blends with chaining.


Recognize Feature Blend Interactive

Recognizes transition features such as Blend features from the selected Solid Face. It can recognize

constant radius and variable radius blends. The dependency relations between different blends are also

recognized.


356

Recognize Feature Chamfer Automatic

Recognizes transition features such as Chamfer features from the selected Solid. The dependency

relations between different chamfers are also recognized.


Recognize Feature Chamfer Interactive

Recognizes transition features such as Chamfer features from the selected Solid Face. The dependency

relations between different chamfers are also recognized.


358

Edit Hole Feature

Edit the Hole Feature Parameters. The radius and depth parameters for a blind hole or the radius of a

through hole can be edited.


Edit Hole Feature

Edit the four selected holes by changing the radius values from 4 and 5 to 8.


360

Edit Hole Feature

The four selected hole radii changed from values from 4 and 5 to 8.


Edit Hole Feature using Radius Constraint

Edit the Hole Feature Parameters using a Radius Constraint. The radius and depth parameters for a blind


362

hole or the radius of a through hole can be edited.edited.

Edit Hole Feature Using Radius Constraint

Edit the four selected holes by changing the radius values and depth from 3 and 15 to 5 and 5 respectively.


Edit Hole Feature Using Radius Constraint

The four selected holes radii and depths changed from 3 and 15 to 5 and 5 respectively.


364

Edit Blend Feature

Edit the Blend Feature Parameters. The radius R1 and radius R2 parameters for a Constant Radius or a


Variable Radius blend can be edited.

Edit Blend Feature

Edit the four selected blends by changing the R1 and R2 radii from 4 and 4 to 3 and 6 respectively.


366

Edit Blend Feature

The four selected blends R1 and R2 radii changed from 4 and 4 to 3 and 6 respectively.


Edit Blend Feature using Radius Constraint

Edit the Blend Feature Parameters using a Radius Constraint. The radius R1 and Radius R2 parameters

for a Constant Radius or Variable Radius Blend can be edited.


368

Edit Blend Feature Using Radius Constraint

Edit the four selected blends by changing the R1 and R2 radii from 5 and 5 to 10 and 10 respectively.


Edit Blend Feature Using Radius Constraint

The four selected blends R1 and R2 radii changed from 5 and 5 to 10 and 10 respectively.


370

Edit Chamfer Feature

Edit the Chamfer Feature Parameters. The height H1 and height H2 parameters for a chamfer can be

edited.



Edit the three selected Chamfers by changing the H1 and H2 heights from 3 and 3 to 5 and 5 respectively.


372


The three selected Chamfers H1 and H2 heights changed from 3 and 3 to 5 and 5 respectively.


Edit Chamfer Feature using Height Constraint


374

Edit the Chamfer Feature Parameters using a Height Constraint. The height H1 and height H2 parameters

for a chamfer can be edited.

Edit Chamfer Feature Using Height Constraint

Edit the three selected chamfers by changing the H1 and H2 heights from 2 and 2 to 4 and 4 respectively.


Edit Chamfer Feature Using Height Constraint

The three selected chamfers H1 and H2 heights changed from 2 and 2 to 4 and 4 respectively.


376

Edit Feature Parameters

The Edit Feature Parameters form allows the feature name and parameters to be displayed and modified

for alteration of a model.


When a column of the spreadsheet is selected, the value is copied to the input databox for editing. Once

the value is modified, press return to update the selected column with the new parameter definition. When

all the desired parameter values are modified, press the OK button to save the changes.

If the Feature Name is changed and the same name is used for multiple feature names, the feature label

will be appended to the input name. For example, if you entered “test” for the name of Hole 1 and Hole

2, then the resulting name for Hole 1 will be “test” and the name for Hole 2 will be test 2.

Show Hole Feature

Show the Hole Feature Parameters. The radius and depth parameters and the number of faces for each

hole is displayed.


378

Show Hole Feature using Radius Constraint

Show the Hole Feature Parameters using a Radius Constraint. The radius and depth parameters and the

number of faces for each hole is displayed.


Show Blend Feature

Show the Blend Feature Parameters. The radius R1 and radius R2 parameters and the number of faces

for each blend is displayed.


380

Show Blend Feature using Radius Constraint

Show the Blend Feature Parameters using a Radius Constraint. The radius R1 and Radius R2 parameters

and the number of faces for each blend is displayed.


Show Chamfer Feature

Show the Chamfer Feature Parameters. The height H1 and height H2 parameters and the number of faces

for each chamfer is displayed.


382

Show Chamfer Feature using Height Constraint

Show the Chamfer Feature Parameters using a Height Constraint. The height H1 and Height H2

parameters and the number of faces for each chamfer is displayed.


Show Feature Information

The Show Feature Information form allows the parameters of a feature to be displayed.

The spreadsheet shows the following information for each feature selected:

• Feature Name

• Parameter Name 1 and value

• Parameter Name 2 and value

• Number of Faces

Picking a spreadsheet cell will highlight the feature in the Patran secondary highlight color


384

Delete Hole Feature

Delete Hole Features.


Delete Hole Feature using Radius Constraint

Delete Hole Features using a Radius Constraint.


386

Delete Blend Feature

Delete Blend Features.


Delete Blend Feature using Radius Constraint

Delete Blend Features using a Radius Constraint.


388

Delete Chamfer Feature using Height Constraint

Delete Chamfer Features using a Height Constraint.


Delete Chamfer Feature

Delete Chamfer Features.


390

Delete Any Feature

Delete any features in the model.


Clear Feature

Clear features from the feature modeler derived from a solid without deleting the associated geometry.


392

393Chapter 4: Create ActionsCreating Coordinate Frames

Creating Coordinate Frames

Creating Coordinate Frames Using the 3Point Method

The 3Point method creates a rectangular, cylindrical or spherical coordinate frame by specifying three

point locations. The point locations can be points, vertices, nodes or other point locations provided on the

Point select menu. For more information, see Overview of Create Methods For Coordinate Frames.

More Help:


• Topology


Geometry Modeling - Reference Manual Part 2Creating Coordinate Frames

394

Coordinate Frame 3Point Method Example

Creates a cylindrical coordinate frame, Coord 100, using the Create/3Point method. Its origin is located

at [0,0,0]; a point on its Z axis is at [0,0,1]; and a point on the R-Z plane is at [0,0,1]. The coordinate

values are expressed within the global coordinate frame, Coord 0.

Coordinate Frame 3Point Method Example

Creates a cylindrical coordinate frame, Coord 200. Its origin is located at Point 8; a point on its Z axis is

at [x8 y8 2] (which is at the X and Y coordinates of Point 8 and at Z=2); and a point on the R-Z plane is

at Point 6.


Creating Coordinate Frames Using the Axis Method

The Axis method creates a rectangular, cylindrical or spherical coordinate frame by specifying three

point locations for the coordinate frame’s origin, at the first, second or third axis and on one of the

remaining two axes. The point locations can be points, vertices, nodes or other point locations provided

on the Point select menu. See Overview of Create Methods For Coordinate Frames.


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• Topology


Coordinate Frame Axis Method Example

Creates a rectangular coordinate frame, Coord 100, using the Create/Axis method. Its definition is

expressed within the rectangular coordinate frame, Coord 0; its origin is located at [0,0,0]; a point on its

X axis is at Point 20; and a point on its Y axis is at Point 12.


Creating Coordinate Frames Using the Euler Method

The Euler method creates a rectangular, cylindrical or spherical coordinate frame through three specified

rotations about the axes of an existing coordinate frame. See Overview of Create Methods For Coordinate

Frames.


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• Topology



Coordinate Frame Euler Method Example

Creates a spherical coordinate frame, Coord 200, using the Create/Euler method. Its definition is

expressed within the rectangular coordinate frame, Coord 100; its origin is located at Point 14 and it is

rotated 45 degrees about Coord 100’s X axis.


400

Rotation Parameters Subordinate Form Example

The Rotation Parameters subordinate form appears when the Rotation Parameters button is pressed on

the Geometry Application Create/Coord/Euler form. See Creating Coordinate Frames Using the Euler

Method.

This form allows you to define up to three rotations to be performed about the specified Reference

Coordinate Frame axes. The rotations are performed in sequence from top to bottom on the form.


Creating Coordinate Frames Using the Normal Method

The Normal method creates a rectangular, cylindrical or spherical coordinate frame with its origin at a

point location on a specified surface or solid face, and its axis 3 direction normal to the surface or face.

The coordinate frame’s axis 1 direction can be aligned with the surface’s or face’s parametric

direction, and its axis 2 direction will be aligned with the direction or visa versa. See Overview of

Create Methods For Coordinate Frames for more information.

You can plot the parametric and directions by pressing the Parametric Direction button on the

Geometric Properties form under the Display/Display Properties/Geometric menu.

ξ1

ξ2

ξ1

ξ2


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• Topology


• Display>Named Attributes (p. 392) in the Patran Reference Manual

Coordinate Frame Normal Method Example

Creates a rectangular coordinate frame, Coord 1, using the Create/Normal method whose Z axis is normal

to Surface 2 and its origin is at Point 16. Notice that Coord 1’s X and Y axis are aligned with Surface 2’s

and directions. ξ1

ξ2


Coordinate Frame Normal Method On a Face Example

Creates rectangular coordinate frame, Coord 2 at Point 17, whose Z axis is normal to the top face of Solid

1.


404

Creating Coordinate Frames Using the 2 Vector Method

The 2 Vector method creates a rectangular, cylindrical or spherical coordinate frame with its origin at the

designated location. Two of the through coordinate frame axes are defined using existing vectors; their

directions are imposed at the selected origin and the new coordinate frame is then created.


Creating Coordinate Frames Using the View Vector Method

The View Vector method creates a rectangular, cylindrical, or spherical coordinate frame at the

designated origin, using the Euler angles that define the current model orientation within the graphics

viewport.


406

407Chapter 4: Create ActionsCreating Planes

Creating Planes

Creating Planes with the Point-Vector Method

The Point-Vector method creates planes at a point and normal to a vector.

Tip: More Help:


• Topology


Point-Vector Method Example

Creates a plane at a point and normal to a vector.

Geometry Modeling - Reference Manual Part 2Creating Planes

408

Creating Planes with the Vector Normal Method

The Vector Normal method creates Planes whose normal is in the direction of the specified vector and

crosses the vector at a specified offset.


Tip: More Help:


• Topology


Vector Normal Option Example

Creates a plane from Vector 1. The normal of the plane is parallel to the Vector.


410

Creating Planes with the Curve Normal Method

Creating Planes with the Curve Normal Method - Point Option

The Point on Curve method using the Point option creates Planes normal to a tangent vector of a point

along a curve. The plane centroid will be the point location on the curve.


Tip: More Help:


• Topology


Point Option Example

Creates a plane whose normal is parallel to the tangent of Curve 1 on the location where Point 3 is

projected on the curve.


412

Creating Planes with the Curve Normal Method-Parametric Option

The Point on Curve method using the Parametric option creates Planes that are normal to a specified

curve at a parametric position along the curve. The plane centroid will be the parametric position along

the curve.


Tip: More Help:


• Topology


Parametric Option Example

Creates a plane on Curve 1 at the specified parametric location. Its normal is parallel to the tangent of

Curve 1 at that location.


414

Creating Planes with the Plane Normal Method

The Plane Normal method creates a plane normal to an existing plane. The line defined by the projection

of the new plane onto the existing plane is defined by selecting a vector; this vector is projected normally

onto the existing plane. The new plane’s normal direction is defined by the vector cross product of the

existing plane normal by the projected vector.


Creating Planes with the Interpolate Method

Creating Planes with the Interpolate Method - Uniform Option

The Interpolate method creates Planes whose normals are in the direction of the curve tangents at the

interpolating points on the curve. Uniform option will space the planes along the curve based on the equal

arc lengths or equal parametric values upon the user’s choice.


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• Topology


Plane Interpolate Example

Creates planes on curve 1 at the interpolating points. The plane’s normals are parallel to the tangents of

Curve 1 at each location.


Creating Planes with the Interpolate Method - Nonuniform Option

The Interpolate method creates Planes whose normals are in the direction of the curve tangents at the

interpolating points on the curve. Nonuniform option will space the planes along the curve based on the

space ratio applied on the arc length or the parametric values upon the user’s choice.


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Creating Planes with the Least Squares Method

Creating Planes with the Least Squares Method - Point Option

The Least Squares method using the Point option creates Planes that are a least squares fit to a set of

points that are not co-linear.


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• Topology



Creates a plane based on the least squares calculated from Point 1:4.


420

Creating Planes with the Least Squares Method - Curve Option

The Least Squares method using the Curve option creates Planes that are a least squares fit to a non-linear

curve.


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• Topology


Curve Option Example

Creates a plane based on the least squares calculated from Curve 1.


422

Creating Planes with the Least Squares Method - Surface Option

The Least Squares method using the Surface option creates Planes that are a least squares fit to a surface.


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• Topology


Surface Option Example

Creates a plane based on the least squares calculated from Surface 1.


424

Creating Planes with the Offset Method

The Vector Normal method creates Planes whose normal is in the direction of the specified vector and

crosses the vector at a specified offset.


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• Topology


Offset Method Example

Creates planes, which are parallel to Plane 1 but have a offset of 1.0 from each other.


426

Creating Planes with the Surface Tangent Method

Creating Planes with the Surface Tangent Method - Point Option

The Tangent method using the Point option creates Planes that are tangent to a specified surface at a

specified point on the surface. The plane centroid will be the point location on the surface.


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• Topology



Creates a plane which is tangent to Surface 1 at Point 5.


428

Creating Planes with the Surface Tangent Method - Parametric Option

The Tangent method using the Parametric option creates Planes that are tangent to a specified surface at

a parametric position on the surface. The plane centroid will be the tangent point on the surface.


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• Topology


Parametric Option Example

Creates a plane which is tangent to Surface 1 at the specified parametric locations.


430

Creating Planes with the 3 Points Method

The 3 Point method creates Planes which pass through three specified points that are not co-linear. The

plane centroid will be average of the first point.


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• Topology


3 Points Method Example

Creates a plane from Point 1:3.


432

433Chapter 4: Create ActionsCreating Vectors

Creating Vectors

Creating Vectors with the Magnitude Method

The Magnitude method creates Vectors from a specified vector magnitude, direction and base point. The

base point can be expressed by cartesian coordinates or by an existing vertex, node or other point location

provided by the Point select menu.

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Geometry Modeling - Reference Manual Part 2Creating Vectors

434

Magnitude Example

Creates a vector based at point 1 and directing along the X axis. The vector has a magnitude of 1.0.

Creating Vectors with the Interpolate Method

Between Two Points

The Interpolate method using the Point option will create n points of uniform or nonuniform spacing

between a specified pair of point locations, where n is the number of interior points to be created. The

point location pairs can be existing points, vertices, nodes or other point location provided by the Point

select menu.


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• Topology

Vector Interpolate Method Example

Creates.


436

Creating Vectors with the Intersect Method

The Intersect method creates Vectors from the intersections of pairs of Planes. The origins of the two

planes will be projected onto the intersection line to determine the base and tip of the resulting vector. If

the base and tip are not unique, the tip will be assumed.


Tip: More Help:


• Topology


Intersect Example

Creates a vector along the intersection of Plane 1 and Plane 2.


438

Creating Vectors with the Normal Method

Creating Vectors with the Normal Method - Plane Option

The Normal method using the Plane option creates Vectors from normal vectors to a Plane; originating

at the plane and passing through a point. The tip point can be expressed by cartesian coordinates or by an

existing vertex, node or other point location provided by the Point select menu.


Tip: More Help:


• Topology


Plane Option Example

Creates a vector which is directing along the normal of Plane 1.


440

Creating Vectors with the Normal Method - Surface Option

The Normal method using the Plane option creates Vectors from normal vectors to a Plane. The base

point can be expressed by cartesian coordinates or by an existing vertex, node or other point location

provided by the Point select menu.


Tip: More Help:


• Topology


Surface Option Example

Creates a vector which is directing along the normal of Surface 1 at Point 5.


442

Creating Vectors with the Normal Method - Element Face Option

The Normal method using the Element Face option creates Vectors from normal vectors to an Element

Face. The base point of the vector will be the element face centroid by default, but a node on the element

face may also be specified.


Tip: More Help:


• Topology


Element Face 2D Option Example

Creates a vector along the normal of the element face at Node 6.


444

Element Face 3D Option Example

Creates a vector along the normal of the element face at Node 2.


Creating Vectors with the Product Method

The Product method creates vectors of the cross products of two existing vectors. The base point of the

created vector will be the base point of the first vector.


446

Tip: More Help:


• Topology


Product Example

Creates Vector 3, which is the cross product of Vector 1 and Vector 2.


Creating Vectors with the 2 Point Method

The 2 Point method creates vectors between two existing point locations. The point locations can be

existing points, vertices, nodes, or other point locations provided on the Point select menu.


448

Tip: More Help:


• Topology


2 Point Option Example

Creates a vector starting from Point 1 and ending at Point 2.

Geometry Modeling - Reference Manual Part 2Creating P-Shapes

450

Creating P-Shapes

Rectangle

The rectangle is defined by an origin point p1, a corner point p2 along direction-1 or the u-direction, and

a corner point p3 along direction-2 or the v-direction. All points are given with respect to the Reference

Coordinate Frame. The point p3 is constrained to be orthogonal to the vector p1-p2 and will be corrected

as necessary.

Quadrilateral

A Quadrilateral is defined by an origin point p1, and corner points p2 in direction-1 (u-direction), and p3

in direction-2 (v-direction), and an opposite corner p4 in the Reference Coordinate Frame.

451Chapter 4: Create ActionsCreating P-Shapes

Triangle

A triangle is defined by an origin point p1, and corner points p2 in direction-1 (u-direction) and p3 in

direction-2 (v-direction). In Patran, the triangle is created as a bi-parametric surface and has one

degenerate side at the origin point p1.


452

Disc

A disc is defined by an external and internal diameter. It is defined in a Reference Coordinate Frame

with an Axis of Revolution shown as the vector p1-p2. The Angle Origin Vector is shown as vector p1-

p3 and the start and end angle are measured in degrees circumferentially from that vector.


Cylinder

A cylinder is defined by a diameter in a Reference Coordinate Frame with an Axis of Revolution shown

as the vector p1-p2. This vector also gives the height of the cylinder. The Angle Origin Vector is shown

as vector p1-p3 and the start and end angle are measured in degrees circumferentially from that vector.


454

Cone

A cone is defined by diameters at the base and apex in a Reference Coordinate Frame with an Axis of

Revolution shown as the vector p1-p2. This vector also gives the height of the cone. The Angle Origin

Vector is shown as vector p1-p3 and the start and end angle are measured in degrees circumferentially

from that vector.


Sphere

A sphere is defined by a diameter in a Reference Coordinate Frame with an Axis of Revolution shown

as the vector p1-p2. The Angle Origin Vector is shown as vector p1-p3 and the start and end angle are

measured in degrees circumferentially from that vector.

The sphere may be truncated at the poles. The base truncation gives the height of the sphere from the

equator to the “bottom” of the sphere. If the negative truncation distance is equal to the radius, then the

sphere is not truncated. The same applies to the apex truncation. Note that a negative truncation distance

measures “below” the equator while a positive truncation measures “above” the equator.


456

Paraboloid

A paraboloid is defined by a diameter in a Reference Coordinate Frame with an Axis of Revolution

shown as the vector p1-p2. This vector also gives the un-truncated height of the paraboloid. The Angle

Origin Vector is shown as vector p1-p3 and the start and end angle are measured in degrees

circumferentially from that vector.

The paraboloid may be at the apex and also at the base. Both truncations are measured from the apex of

the paraboloid.


Five-Sided Box

A Five-sided box is defined as a solid, but is an open-shell meaning that it is a connected set of five

surfaces which is not closed. The five-sided box is defined with dimensions dx, dy, and dz in the x, y,

and z directions at the global origin. The face that is "missing" from the 5-sided box is the z+ face. At

the time of creation, a local coordinate frame is used to create the solid at a user-prescribed location. The

local coordinate frame is represented by an axis which defines the local origin of the solid at the axis

begin point and the x-direction of the solid. The y-direction is defined by a vector. The z-direction is

defined ortho-normal to the x-y plane.


458

Six-Sided Box

A Six-sided Box is a parameterized solid defined with dimensions dx, dy, and dz in the x, y, and z

directions at the global origin. At the time of creation, a local coordinate frame is used to create the solid

at a user-prescribed location. The local coordinate frame is represented by an axis which defines the local

origin of the solid at the axis begin point and the x-direction of the solid. The y-direction is defined by

a vector. The z-direction is defined ortho-normal to the x-y plane.

Geometry Modeling - Reference Manual Part 2Edit P-Shapes

460

Edit P-Shapes

This form is used to edit P-Shapes by their parameters. One or more P-Shapes of the same type may be

modified. A P-Shape may be selected by its label. The P-Shapes listed in the listbox may be filtered by

name or by type, e.g., Rectangle, Triangle, etc. P-Shapes which are listed in the listbox may be displayed

on the screen using the “Show P-Shape” button and the display is reset using the “Reset” button.

P-Shapes can also be selected off the screen using the “Select P-Shape(s)” select data box . Since

different types of P-Shapes may be selected in either the listbox or in the select data box, the “Filter for

P-Shape(s)” button is used to isolate one type of P-Shape.

If only entity is selected for edit, then you can edit the P-Shape Label. The parameters to edit are identical

to the Create P-Shape forms for each geometry type. If multiple entities are selected, certain parameters

may not be editable such as the Axis of Revolution for cones (spheres, paraboloids) since modifying that

parameter to be the same will transform all cones edited to be in the same location.

Chapter 5: Delete Actions


5 Delete Actions

� Overview of the Geometry Delete Action 462

� Deleting Any Geometric Entity 463

� Deleting Points, Curves, Surfaces, Solids, Planes or Vectors 464

� Deleting Coordinate Frames 466

Geometry Modeling - Reference Manual Part 2Overview of the Geometry Delete Action

462

Overview of the Geometry Delete Action

The Geometry Application Delete action can remove any or all geometric entities from the database.

Objects that are available for deletion are listed in Table 5-1.

Auto Execute Is Off By Default

By default, the Auto Execute toggle is OFF. For more information, see Auto Execute (p. 26) in the

Patran Reference Manual.

Using the Abort and Undo Buttons

When the Delete action form starts to execute, you may press the Abort key at any time to halt the delete

process. You may also press the Undo button immediately after the Delete action completes to restore

the deleted entities back to the database. See System Tool Palette (p. 14) in the Patran Reference Manual

for more information.

Table 5-1 Geometry Delete Action Objects and Descriptions

Object Description

Any Deletes different types of geometric entities at the same time.

Point Deletes any number of points.

Curve Deletes any number of curves.

Surface Deletes any number of surfaces.

Solid Deletes any number of solids.

Coord Deletes any number of user defined coordinate frames.

463Chapter 5: Delete ActionsDeleting Any Geometric Entity

Deleting Any Geometric Entity

Setting the Object menu to Any deletes any number of points, curves, surfaces, solids or coordinate

frames (except the global coordinate frame, Coord 0) from the database. You can also delete geometric

entities by using the Group/Delete menu.

Tip: More Help:


• Group>Delete (p. 289) in the Patran Reference Manual

Geometry Modeling - Reference Manual Part 2Deleting Points, Curves, Surfaces, Solids, Planes or Vectors

464

Deleting Points, Curves, Surfaces, Solids, Planes or Vectors

Setting the Object menu to Point, Curve, Surface, Solid, Plane or Vector removes any number of

specified points, curves, surfaces, solids, planes or vectors from the database.

465Chapter 5: Delete ActionsDeleting Points, Curves, Surfaces, Solids, Planes or Vectors

Tip: More Help:

• The List Processor (p. 43) in the Patran Reference Manual

• Group>Delete (p. 289) in the Patran Reference Manual

Geometry Modeling - Reference Manual Part 2Deleting Coordinate Frames

466

Deleting Coordinate Frames

Setting the Object menu to Coord removes any number of specified user defined coordinate frames from

the database The global rectangular coordinate frame, Coord 0, cannot be deleted. Also, a coordinate

frame will not be deleted if it is being referenced as a Nodal Reference Coordinate Frame or Analysis

Coordinate Frame, elsewhere in the model.

Tip: More Help:

• The List Processor (p. 43) in the Patran Reference Manual


• Node Coordinate Frames (p. 47) in the Reference Manual - Part III

Chapter 6: Edit Actions


6 Edit Actions

� Overview of the Edit Action Methods 470

� Editing Points 472

� Editing Curves 474

� Editing Surfaces 520

� Editing Solids 591

� Editing Features 634

Geometry Modeling - Reference Manual Part 2Overview of the Edit Action Methods

470

Overview of the Edit Action Methods


Point • Equivalence • Finds groups of points which are within global model tolerances

of each other and for each group, equivalences the points into

one point.

Curve • Break • Breaks curves into n+1 curves at either a point location or at a

parametric coordinate location.

• Blend • Creates curves from two or more curves or edges by forcing a

first derivative continuity across the boundaries.

• Disassemble • Creates curves that represent a specified chained curve.

• Extend • Extends or lengthens one curve or edge or a pair of curves or

edges, either through a straight line extension, or through a

continuous curvature.

• Merge • Creates one or more curves from an existing set of curves or

edges. Some of the original curvature may be lost.

• Refit • Creates Uniformly parameterized Piecewise Cubic curves from

existing curves.

• Reverse • Redefines the connectivity of a curve or edge by reversing the

curve’s or edge’s positive parametric direction.

• Trim • Shortens the length of a curve or edge at either a point location or

a parametric coordinate location on the curve.

Surface • Break • Breaks a surface or a solid face into two or four smaller surfaces

at either a point, curve or surface location, or at a parametric

coordinate location on the surface.

• Blend • Creates surfaces from two or more surfaces or solid faces by

forcing a first derivative continuity across its boundaries. A

parametric green surface is required for this operation to work.

• Disassemble • Creates surfaces that represent the specified B-rep solid.

• Edge Match • Recreates a specified surface either by closing a gap between it

and another adjacent surface; or by creating an additional vertex

and converting the surface into a trimmed surface.

• Extend • Extends or lengthens a surface: by a percentage in the U and/or V

parametric directions, to its intersection with a curve, plane,

point or another surface, or by a fixed length. Also extends a pair

of surfaces to their intersection.

• Refit • Creates a non-uniformly parameterized network of bicubic

patches from existing surfaces.

• Reverse • Redefines the connectivity of a surface or solid face by reversing

the surface’s or face’s positive parametric directions.

471Chapter 6: Edit ActionsOverview of the Edit Action Methods

• Sew • Combines Edit, Point, Equivalence and Edit, Surface, Edge

Match functionality to equivalence surface vertices and merge

edges.

Solid • Break • Breaks a solid into two, four or eight smaller solids either at a

point, curve or surface location, or at a parametric coordinate

location.

• Blend • Creates solids from two or more solids by forcing a first

derivative continuity across its boundaries.

• Disassemble • Creates surfaces that represent a specified B-rep solid.

• Refit • Creates uniformly parameterized Piecewise Cubic solids from

existing solids.

• Reverse • Redefines the connectivity of a solid by reversing the solid’s

positive parametric directions.and moving the location of the

parametric origin.

Feature • Suppress • Displays the list of CAD features associated with the geometry

that can be suppressed from the geometric model

• Unsuppress • Displays the list of CAD features associated with the geometry

that can be unsuppressed from the geometric model.

• Parameters • Displays the list of CAD features associated with the geometry

whose parameters can be edited to be used to regenerate the

geometric model based on the new parameter values.


Geometry Modeling - Reference Manual Part 2Editing Points

472

Editing Points

Equivalencing Points

The Point Equivalence method finds groups of points which are within global model tolerance of each

other and for each group and equivalences the points into one point.

Editing Point Equivalence Method Example

Equivalences points 5 and 6 resulting in point 5 at the mid-point between points 5 and 6.

473Chapter 6: Edit ActionsEditing Points

Geometry Modeling - Reference Manual Part 2Editing Curves

474

Editing Curves

Breaking Curves

Breaking a Curve at a Point

The Break method with the Point option creates n+1 curves by breaking an existing curve or edge at one

or more point locations. The point locations can be defined by either existing points, nodes, vertices,

curve/curve intersections, or curve/surface intersections. Also, the break point location does not have to

lie on the curve or edge.

475Chapter 6: Edit ActionsEditing Curves

Tip: More Help:

• Select Menu (p. 33) in the Patran Reference Manual, Part 1: Basic Functions

• Topology (p. 10)

Curve Break Method At a Point Example

Creates Curves 2 and 3 by breaking Curve 1 at Point 2. Notice that Delete Original Curves is pressed in

and Curve 1 is deleted.


476

Curve Break Method Between Two Points Example

Creates Curves 1 and 2 by breaking a curve defined by Points 1 and 2 (by using the Curve select menu

icon listed below) at the break location of Node 1. Notice that Node 1 does not have to be colinear with

Points 1 and 2.


Curve Break Method At An Edge Example

Creates Curves 1 and 2 by breaking an edge of Surface 1 (using the Curve select menu icon listed below)

at the break location defined by Node 1.


478

Breaking a Curve at a Parametric Location

The Break method with the Parametric option creates two curves from an existing curve or edge, at the

curve’s parametric coordinate location, where has a range of .ξ1u( ) ξ

10 ξ

11≤ ≤


More Help:


• Topology

• Connectivity


480


Curve Break Method At a Parametric Location Example

Creates Curves 2 and 3 by breaking Curve 1 at . Notice that Delete Original Curves is pressed

in and the Parametric Direction is turned ON.

ξ1

0.25Z


Curve Break Method At a Parametric Location On An Edge Example

Creates Curves 1 and 2 by breaking an edge of Surface 1 (by using the Curve select menu icon listed

below) at .ξ1

0.25Z


482

Breaking a Curve at a Plane Location

The method breaks a curve with a plane. The curve will be broken at each intersection point with the

plane.


Tip: More Help:


• Topology

• Connectivity



484

Blending a Curve

The Blend method creates a set of parametric cubic curves from an existing set of two or more curves or

edges by enforcing a first derivative continuity across its boundaries. The set of existing curves or edges

must be connected.

Tip: More Help:



• Topology



Curve Blend Method At Weighting Factor = 1.0 Example

Creates Curves 6 through 10 by equally blending Curves 1 through 5. Notice that Delete Original Curves

is pressed in.


486

Curve Blend Method At Weighting Factors Other Than 1.0 Example

This example is the same as the previous example, except that four weighting factors are used for the four

curve pairs: 1e-6, 1.0, 1.0, 1e6.


Disassembling a Chained Curve

The Disassemble method operates on one or more chains (composite curves) and breaks them into the

original curves that composed the chain. A chained curve can be created by using Geometry

Application’s Create/Curve/Chain form. Chained curves are usually used in Patran for creating trimmed

surfaces.


488

Tip: More Help:

• Select Menu (p. 33) in the Patran Reference Manual, Part 1: Basic Functions

• Trimmed Surfaces (p. 20)

• Creating Chained Curves (p. 131)

• Creating Trimmed Surfaces (p. 277)


Curve Disassemble Method Example

Creates Curves 8 through 13 from chained Curve 7. Notice that Delete Original Curves is pressed in and

Curve 7 is deleted.


490

Extending Curves

Extending a Curve With the 1 Curve Option

The Extend method with the 1 Curve option extends one or more curves which start at either the

beginning or the end of an existing curve or edge, and moves in the tangent direction for a defined length.


You can either extend curves in a straight line or maintain the same curvature as the existing curve or

edge.


492


Tip: More Help:


• Topology

• Understanding the List Processor (p. 766) in the Patran Reference Manual

Curve Extend Method For One Curve Example

Extends curve 1 in a straight line by an actual length of 1.0.


494

Curve Extend Method For One Curve Example

This example is the same as the previous example, except Continuous Curvature is pressed in, instead of

Straight Line, and Fraction of Original is pressed in based on a value of 1.5.


Curve Extend Method For One Edge Example

Creates Curve 1 by extending it from an edge of Surface 1 (by using the Curve select menu icon listed

below). Both Straight Line and Actual are pressed in, with a length of 1.0 entered.


496

Extending a Curve Using the Through Points Type

The Extend method with the 1 Curve option using the Through Points switch modifies one curve by

extending the curve through N-points.


Tip: More Help:


• Topology



498

Curve Extend Method For Through Points Example

Extends Curve 1 by passing through the selected screen points.


Extending a Curve Using the Full Circle Type

The Extend method with the 1 Curve option using the Full Circle switch creates one curve by extending

the curve to a full circle, given the start, end, or interior point of the curve. If the curve has zero radius of

curvature, a circle will not be created.


500

Tip: More Help:


• Topology



Curve Extend Method For Full Circle Example

Extends Curve 1 to a full circle by selecting Curve 1 and then Point 1.

Extending a Curve With the 2 Curve Option

The Extend method with the 2 Curve option extends a set of curves in a straight line by extending them

from two existing curves or edges. Patran will extend the specified endpoints to where the two curves


502

will intersect. If the distance from the intersection to the endpoint of one of the existing curves, is within

a distance of the Global Model Tolerance, then Patran will extend only one curve instead of two. (The

Global Model Tolerance is defined on the Global Preferences form under the Preferences/Global menu).

Tip: More Help:


• Topology



Curve Extend Method For Two Curves Example

Extends Curves 1 and 2 to their point of intersection.

Curve Extend Method For A Curve and An Edge Example

Creates Curve 3 and extends Curve 1 by extending them from Curve 1 and an edge of Surface 1 by using

the Curve select menu icon listed below.


504

Merging Existing Curves

The Merge method creates one or more curves from an existing set of curves or edges. The shape of the

new curves, relative to the existing curves or edges, will be preserved to the extent possible, but, in

general, some detail will be lost. The existing curves or edges must be connected.


Tip: More Help:


• Parameterization

• Topology




506

Curve Merge Method Example

Creates Curve 6 by merging Curves 1 through 5. Notice that Delete Original Curves is pressed and

Curves 1 through 5 are deleted.


This example is the same as the previous example, except that the merge tolerance is 0.00001.



Creates Curves 6 through 8 from merging Curves 1 through 5.


508

Refitting Existing Curves

The Refit method using the Uniform option creates uniformly parameterized Piecewise Cubic curves

from existing curves. The number of piecewise cubic segments per curve is input as the refit parameter.


Tip: More Help:



• Topology



510


Reversing a Curve

The Reverse method redefines the connectivity of an existing set of curves or edges by reversing the

positive direction of the curves or edges. You can plot the curve’s direction by selecting the

Parametric Direction toggle on the Geometric Properties form found under the menus Display/Display

Properties/Geometric.

ξ1

ξ1


Tip: More Help:


• Topology

• Connectivity



512

Curve Reverse Method Example

This example reverses Curves 6, 7 and 8. Notice that the parametric direction is displayed for the curves.

Curve Reverse Method With Associated Elements Example

This example is the same as the previous example, except Curves 7, 8 and 9 have associated bar elements.

Although the node IDs are not reversed, Patran internally reverses the bar elements’ connectivities. For

example, for Bar 1 the nodes are stored as Nodes 2 and 1, instead of 1 and 2.


Trimming Curves

Trimming a Curve With the Point Option

The Trim method with the Point option modifies an existing set of curves by trimming them at a specified

point location along each curve. The trim point can be defined by either existing points, nodes,

curve/curve intersections, or curve/surface intersections. You cannot trim existing edges.


514

Tip: More Help:


• Topology

Curve Trim Method At a Point Example

Trims Curve 9 at Point 9, with Point 9 cursor selected in the Curve/Point List as end of the curve to

discard or trim off.


Curve Trim Method At a Point Example

Trims Curve 9 at the intersection of Curves 9 and 10 by using the Point select menu icon listed below for

the Trim Point List. Point 8 is cursor selected for the Curve/Point List as the end of the curve to trim.


516

Trimming a Curve Using the Parametric Option

The Trim method using the Parametric option modifies an existing set of curves by trimming them at a

specified parametric coordinate location, where has a range of . You cannot trim existing

edges.

ξ1

ξ1

0 ξ1

1≤ ≤


Tip: More Help:


• Topology

• Connectivity



518

Curve Trim Method At a Parametric Location Example

Trims Curve 9 at , where Point 8 is cursor selected as the end of the curve to trim.

Curve Trim Method At a Parametric Location Example

This example is the same as the previous example, except Point 1 instead of Point 8 is cursor selected as

the end of the curve to trim in the Curve/Point List box.

ξ1u( ) 0.75Z

Geometry Modeling - Reference Manual Part 2Editing Surfaces

520

Editing Surfaces

Surface Break Options

Breaking a Surface With the Curve Option

The Break method with the Curve option creates two surfaces by breaking a surface or solid face at a

curve location.The curve location does not have to lie on the surface, but it must intersect on opposite

edges of the surface or face. The curve location can be a curve, an edge or other curve locations provided

on the Curve select menu.

521Chapter 6: Edit ActionsEditing Surfaces

Tip: More Help:


• Topology

Surface Break Method At a Curve Example

Breaks Surface 1 at Curve 3. Notice that Curve 3 does not lie on Surface 1. Instead, Patran projects the

curve break location on the surface. Also, Delete Original Surfaces is pressed in and Surface 1 is deleted.


522

Surface Break Method At Two Points Example

This example is the same as the previous example, except the curve break location is defined by Points

8 and 9 using the Curve select menu icon listed below.


Surface Break Method At a Curve on a Face Example

Breaks a face of Solid 1 using the Surface select menu icon listed below, at the break location of Curve 1.


524

Breaking a Surface With the Surface Option

The Break method with the Surface option creates two surfaces by breaking a surface or solid face at a

surface location.The surface break location must intersect the surface or face on opposite edges. The

surface break location can be a surface or a solid face.


Tip: More Help:


• Topology

Surface Break Method At a Surface Example

Creates Surface 4 and 5 by breaking Surface 1 in half with the break location of Surface 3.


526

Breaking a Surface With the Plane Option

This method breaks a surface with a plane. The surface will be broken along its intersection with the

plane.


Tip: More Help:


• Topology

Breaking a Surface With the Plane Option Example

Creates Surfaces 3 and 4 by breaking Surface 2 in half with the break location of Plane 1.


528

Breaking a Surface With the Point Option

The Break method with the Point option creates two or four surfaces by breaking an existing surface or

solid face defined at a point location. If the point is on an edge, then two surfaces are created. If the point

is located on the interior, then four surfaces are created. The point location can be a point, a node, a

vertex, a curve/curve intersection or a curve/surface intersection.


Tip: More Help:


• Topology

Surface Break Method At a Point Example

Breaks Surface 1 into four Surfaces at Point 5. Notice that Delete Original Surfaces is pressed and

Surface 1 is deleted.


530

Surface Break Method At a Point Example

This example is the same as the previous example, except that the break location is at Point 4 instead of

Point 5, and Surfaces 2 and 3 are created instead of four surfaces.


Surface Break Method At a Vertex Example

Breaks Surface 1 along the diagonal into Surfaces 2 and 3 at Point 1 which is located at the vertex of

Surface 1.


532

Breaking a Surface Using the 2 Point Option

The Break method using the 2 Point option creates two surfaces by breaking an existing surface or solid

face defined by two point locations. The point locations must lie on opposite edges of the surface or face.

The point locations can be points, nodes, vertices, curve/curve intersections, or curve/surface

intersections.


Tip: More Help:


• Topology

Surface Break Method At 2 Points Example

Breaks Surface 1 into Surfaces 2 and 3 defined by Point 5 and Node 1. Notice that Delete Original

Surfaces is pressed in and Surface 1 is deleted.


534

Breaking a Surface With the Parametric Option

The Break method with the Parametric option creates two surfaces from an existing surface or solid face.

The break location is defined at the surface’s or face’s parametric or coordinate location, where

has a range of and has a range of .

ξ1

ξ2

ξ1

0 ξ1

1≤ ≤ ξ2

0 ξ2

1≤ ≤


Tip: More Help:


• Topology

• Connectivity



536

Surface Break Method At Parametric Location u=0.25 Example

Breaks Surface 1 into Surfaces 2 and 3 at . Notice that Delete Original Surfaces is pressed

and Surface 1 is deleted and that the parametric direction is displayed.

Surface Break Method At Parametric Location v=0.25 Example

This example is the same as the previous example, except that the break location is at .

ξ1u( ) 0.25Z

ξ2v( ) 0.25Z


Surface Break Method On a Face At Parametric Location v=0.25 Example

Breaks a face of Solid 1 by using the Surface select menu icon listed below at .ξ2v( ) 0.25Z


538

Blending Surfaces

The Blend method creates a set of parametric bi-cubic surfaces from an existing set of two or more

surfaces or solid faces by enforcing a first derivative continuity across its boundaries. The set of existing

surfaces or faces must share at least one edge with another surface or face in the set.


Tip: More Help:


• Topology


Note: A parametric green surface is required for this operation to work.


540

Surface Blend Method Example

Blends Surfaces 1, 5, 3 and 4 with a default weight factor of 0.5 applied to all surface edges.

Surface Blend Method Example

Blends Surfaces 1 through 4 with a weighting factor of 1.0 applied to two edges (highlighted in the

“Before” picture).


Disassembling Trimmed Surfaces

The Disassemble method operates on one or more trimmed surfaces and creates the parent surface that

has the same curvature as the trimmed surface. A trimmed surface can be created either by using the

Geometry Application’s Create/Surface/Trim form or by using the Create/Surface/Planar Trim form.


542

Tip: More Help:



• Creating Trimmed Surfaces


Surface Disassemble Method Example

Operates on Surface 2 which is a general trimmed surface. Surface 3 is the new parent surface. Notice

that new curves associated with Surface 2 are also created.

Surface Disassemble Method Example

Operates on Surface 1 which is a planar trimmed surface. Notice that the new parent surface, Surface 2,

is also planar and that new curves associated with Surface 1 are created.


544

Editing Edges from Surfaces

Removing Edges from Surfaces with Edge Option

With this form you can remove a given edge of a trimmed surface. This process differs from the vertex

removal function which was topological in nature. This operation is both topological and geometrical in

that the shape of the trimmed surface will be altered as well as the topology. The edges adjacent to the


removed edge will be extended until they intersect. This intersection must take place within the domain

of the parent surface.

Removing Edges from Surfaces with Edge Length Option

With this form you can automatically remove all edges whose length is less than a specified value.


546

Adding Edges from Surfaces

With this form you can automatically add edges to a surface.


Replacing Edges from Surfaces

With this form you can automatically replace edges on a specified surface with an existing curve.


548

Matching Surface Edges

Matching Surface Edges with the 2 Surface Option

The Edge Match method with the 2 Surface option recreates the second surface of a specified pair that


share two common vertices but has a gap or unmatched edges. The gap must be less than 10 times the

Global Model Tolerance or else Patran will not close the gap. The existing pair of surfaces or faces do

not need to have matching parametric and orientations. This method is useful for correcting

topologically incongruent surface pairs so that they are congruent before you mesh. Also see Matching

Adjacent Surfaces, 269.

Tip: More Help:


• Topology

• Topological Congruency and Meshing

ξ1

ξ2


550

Surface Edge Match Method Example

Edits Surface 2 which is specified as the second surface of the pair and closes the gap between Surfaces

1 and 2.

Surface Edge Match Method Example

This example is the same as the previous example, except Surface 1 is specified as the second surface of

the surface pair.


Matching Surface Edges with the Surface-Point Option

The Edge Match method with the Surface-Point option recreates a specified surface as a trimmed surface

that includes an additional cursor defined vertex point. This method is useful for correcting topologically

incongruent pairs of surfaces so that they are congruent before you mesh.


552

Tip: More Help:


• Topology


Surface Edge Match Method With Surface-Point Example

Recreates Surface 1 which was a parametric bi-cubic surface, into a trimmed surface which has the

vertices Points 1, 2, 3, 4 and 5 so that Surface 1 is congruent with Surfaces 2 and 3. The additional vertex


specified in the Point List was cursor selected at Point 5 by using the Vertex select menu icon listed

below.

Extending Surfaces

Extending Surfaces with the 2 Surface Option

This form is used to extend two surfaces to their line of intersection.


554

Tip: More Help:


Extending a Surface With the 2 Surface Option Example

Extend surface 1 to the line of intersection of surface 2.


Extending Surfaces to a Curve

This form is used to extend a surface to an intersecting curve.


556

Tip: More Help:


Extending a Surface to a Curve Example

Extend Surface 1 to the edge of Surface 2.


Tip: More Help:


Extending Surfaces to a Plane

This form is used to extend a surface to an intersecting plane.


558

Tip: More Help:


Extending a Surface to a Plane Example

Extend Surface 1 to Plane 1.


Extending Surfaces to a Point

This form is used to extend a surface to an intersecting point.


560

Extending a Surface to a Point Example

Extend Surface 1 to Point 1.


Extending Surfaces to a Surface

This form is used to extend a surface to an intersecting surface.


562

Tip: More Help:



Extending a Surface to a Surface Example

Extend Surface 1 to the line of intersection of Surface 2 and break Surface 2 at the line of intersection to

create Surface 3 and 4, then delete Surface 2.


564

Extending Surfaces with the Percentage Option

This form is used to extend a surface by a percentage in the U and/or V parametric directions.


Tip: More Help:


Extending a Surface With the Percentage Option Example

Extend Surface 1 by 100% in the U direction starting at U-Max = 1 and shrink Surface 1 by 50% in the

V direction starting at V-Max=1.


566

Extending Surfaces with the Fixed Length Option

This form is used to extend a surface by a fixed length.


Tip: More Help:


Extending a Surface With the Fixed Length Option Example

Extend Surface 1 by a fixed length of 5.0 units in the X direction.


568

Refitting Surfaces

The Refit method creates a non-uniformly parameterized network of bicubic patches from existing

surfaces. The Refit Tolerance is input as the refit parameter.


Tip: More Help:


• Topology



570

Reversing Surfaces

The Reverse method redefines the connectivity of an existing set of surfaces or solid faces by exchanging

the positive and directions of the surfaces or faces. You can plot the and directions for the

surfaces by pressing the Show Parametric Direction toggle on the Geometric Attributes form found under

the menu Display/Geometry.

Tip: More Help:


• Topology

ξ1

ξ2

ξ1

ξ2


• Connectivity


• Showing Surface Attributes

Surface Reverse Method Example

Reverses the parametric and directions for Surface 1. Notice that the parametric directions are

displayed on the surfaces. Also, notice that Auto Execute is not on so that you can press the Draw Normal

Vectors button without executing the form.

ξ1

ξ2


572

Sewing Surfaces

The Sew method sequentially combines the actions of the Edit/ Point/ Equivalence method to

equivalence surface vertices and the Edit/ Surface/Edge Match method to merge edges. The composite

action is a "sewing" of the surfaces. Vertices and edges are both equivalenced according to the

restrictions of the previously mentioned methods; however, since the operation is sequential, vertices will

already be equivalenced before doing the edge merging.


Surface Sew Method Example

Edits surfaces 1 and 2 by closing the gap between edges which share common vertices.


574

Subtracting Surfaces

The Subtract method .


Trimming Surfaces to an Edge

This form is used to trim a Surface with one of its edges and optionally delete the surface with the

smallest surface area after the trim.


576

Tip: More Help:


Trim Surface To Edge Example

Trim the sliver from surface 5 by selecting the surface edge surface 5.4.


Adding a Fillet to a Surface

This form facilitates the creation of a fillet edge between two existing edges sharing a given vertex. This

operation, when successful will replace the input vertex with a new edge.


578

Adding a Hole to Surfaces

Adding a Hole to Surfaces with the Center Point Option

The Add Hole method using the Center Point option adds a circular hole to a Surface. The circular hole

is defined in the tangent plane of the supplied, manifolded center point.


Tip: More Help:


Adding a Hole to a Surface with the Center Point Option Example

This will add nine circular holes to surface 1 using points 52:60. Warning messages will be generated for

the other points due to interference of holes at these points with surface edges.


580

Adding a Hole to Surfaces with the Project Vector Option

The Add Hole method using the Projection Vector option adds a circular hole to a Surface. The circular

hole is defined in the plane of the supplied vector and vector-projected onto the surface.


Tip: More Help:


Adding a Hole to a Surface with the Project Vector Option codeindent10

This will add two holes to surface 6 using points 78 and 82 and the projection vector defined by the x

axis of Coordinate Frame 0.


582

Adding a Hole to Surfaces with the Inner Loop Option

The Add Hole method using the Inner Loop option adds a hole to a Surface. The hole is defined by the

supplied closed, chained curves which will define inner loops for the creation of a Trimmed Surface.


Tip: More Help:


Adding a Hole to a Surface with the Inner Loop Option Example

This will add 5 new holes to surface 6 using curves 14, 15, 16, 29, and 30.


584

Removing a Hole from Trimmed Surfaces

The Remove Hole method removes a hole from a Trimmed Surface. The hole to remove can be any edge-

curves which are inner loops of a Trimmed Surface.


Tip: More Help:


Removing a Hole from a Trimmed Surface Example

This will remove all the small inner loops from surface 4.


586

Adding a Vertex to Surfaces

The Add Vertex method adds a vertex to a surface. The point used to create a vertex can be any point

which is on the edge of the selected surface. If a hardpoint is converted to a surface vertex in the process

of adding a vertex to a surface, then this point(vertex) cannot be reassociated to the surface as a hardpoint.


Tip: More Help:


Adding a Vertex to a Surface Example

This will add a vertex to surface 2 using point 3. The result is surface 2 becomes a trimmed surface with

five vertices.


588

Removing a Vertex from Trimmed Surfaces

The Remove Vertex method removes a vertex from a Trimmed Surface. The vertex to remove can be any

vertex of a Trimmed Surface with the exception that one vertex per loop must remain.


Tip: More Help:


Removing a Vertex from a Trimmed Surface Example

This will remove vertex 3.4.2 from trimmed surface 3. The result is a parametric bicubic surface.


590

591Chapter 6: Edit ActionsEditing Solids

Editing Solids

Breaking Solids

Breaking Solids with the Point Option

The Break method with the Point option breaks an existing solid into two or four smaller solids at a point

location. The point location can be on or within the solid.

More Help:


Geometry Modeling - Reference Manual Part 2Editing Solids

592


• Topology

Solid Break Method with the Point Option Example

Breaks Solid 1 into eight solids by referencing Point 9. Notice that Delete Original Surfaces is pressed

and Solid 1 is deleted.



This example is similar to the previous example, except that the break point is on a face instead of inside

of Solid 1, and four solids are created instead of eight.


594


This example is similar to the previous example, except that the break point is on an edge instead of on

a face of Solid 1, and two solids are created instead of four.


Breaking Solids with the Parametric Option

The Break method with the Parametric option creates two, four or eight solids from an existing solid. The

break location is defined at the solid’s parametric , , and coordinate locations where has a

range of , has a range of and has a range of .

ξ1

ξ2

ξ3

ξ1

0 ξ1

1≤ ≤ ξ2

0 ξ2

1≤ ≤ ξ3

0 ξ3

1≤ ≤


596


Tip: More Help:


• Topology

• Connectivity


Solid Break Method with the Parametric Option Example

Breaks Solid 1 into eight smaller solids at , , and . Notice that Delete Original

Surfaces is pressed and Surface 1 is deleted and that the parametric direction is displayed.

ξ1

0.5Z ξ2

0.5Z ξ3

0.5Z


598


This example is similar to the previous example, except instead of , and Surface 1 is

broken into four solids instead of eight.

ξ1

0Z ξ1

0.5Z



This example is similar to the first example, except and instead of and ,

and Surface 1 is broken into two solids instead of eight.

ξ1

0Z ξ2

0Z ξ1

0.5Z ξ2

0.5Z


600

Breaking Solids with the Curve Option

The Break method with the Curve option breaks an existing solid into two solids at a curve break location.

The curve location must completely lie on and bisect a face of the solid.


Tip: More Help:



• Topology

Solid Break Method with the Curve Option Example

Breaks Solids 2 and 3 into two solids each at Curve 1. Notice that Delete Original Solids is pressed and

Solid 1 is deleted.


602

Breaking Solids with the Plane Option

The method breaks a solid with a plane. The solid will be broken along its intersection with the plane.


Tip: More Help:



• Topology


604

Breaking a Solid with the Plane Option Example

Creates Solids 2 and 3 by breaking Solid 1 along its intersection with Plane 1. Notice that Delete Original

Solids is pressed and Solid 1 is deleted.

Breaking Solids with the Surface Option

The Break method with the Surface option breaks an existing solid into two smaller solids at a surface

break location. The surface break location must completely pass through the solid.


Tip: More Help:



• Topology

Solid Break Method with the Surface Option Example

Breaks Solid 1 into two solids at Surface 1. Notice that Delete Original Solids is pressed and Solid 1 is

deleted.


606

Solid Break Method with the Surface Option Between Two Surfaces Example

This example is the same as the previous example, except that the solid is defined by Surfaces 2 and 3 by

using the Solid select menu icon listed below.


Blending Solids

The Blend method creates a set of parametric tri-cubic solids from an existing set of two or more solids,

such that the first derivative continuity is maintained across the surface boundaries between adjacent

solids. The existing solids can have any parametrization, but they must share common faces.


608

Tip: More Help:



• Topology


Solid Blend Method Example

Creates Solids 4, 5 and 6 by blending Solids 1, 2 and 3. Notice that Delete Original Solids is pressed and

Solids 1, 2 and 3 are deleted.


Solid Blend Method Example

This example is similar to the previous example, except that weighting factors, 1e6 and 1e-6, are used so

that Solids 1 and 3 dominate the slope.


610

Disassembling B-rep Solids

The Disassemble method operates on one or more boundary represented (B-rep) solids and breaks them

into the original surfaces that composed each B-rep solid. A B-rep solid can be created by the Geometry

Application’s Create/Solid/B-rep form.


Tip: More Help:



612

Disassemble a B-rep Solid Example

Disassemble solid 1 into its constituent surfaces and convert all possible surfaces into Simply Trimmed

surfaces (green). If “Conver to Simply Trimmed” toggle was OFF, the resulting surfaces would maintain

their original type; (magenta).


Refitting Solids

Refitting Solids with the To TriCubicNet Option

This form is used to refit a solid to alternative mathematical solid representations. The form provides

three Options; To TriCubicNet, To TriParametric, and To Parasolid.


614

Tip: More Help:


• Solids


• Creating a Boundary Representation (B-rep) Solid


Refitting Solids with the To TriParametric Option



Tip: More Help:


• Solids


616



Refitting Solids with the To Parasolid Option




Tip: More Help:


• Solids




618

Reversing Solids

The Reverse method redefines the connectivity of an existing set of solids by exchanging the positive

and directions of the solids. Then, to maintain a positive parametric frame, Patran translates the

parametric origin up the original axis and then reverses the direction. You can plot the , and

directions for the solids by pressing the Show Parametric Direction toggle on the Geometric Attributes

form found under the menu Display/Geometry.

Solid Reverse Method Example

Reverses the parametric directions for Solid 1 (only the top half of Solid 1 is shown). Notice that the

parametric origin is relocated.

ξ1

ξ2

ξ3

ξ3

ξ1

ξ2

ξ3


Solid Boolean Operation Add

This form is used to perform a Solid boolean of “Add”.


620

Tip: More Help:


Solid Boolean Operation Add Example

Add Solids 2 and 3 to Solid 1.


Solid Boolean Operation Subtract

This form is used to perform a Solid boolean operation of “Subtract”.


622

Tip: More Help:


Solid Boolean Operation Subtract Example

Subtract solids 2 and 3 from solid 1.


Solid Boolean Operation Intersect

This form is used to perform a Solid boolean operation of “Intersect”.


624

Tip: More Help:


Solid Boolean Operation Intersect Example

Intersect solids 2 and 3 with solid


Creating Solid Edge Blends

Creating Constant Radius Edge Blends from Solid Edges

This form is used to create a constant radius edge blend on an edge(s) of a solid.


626

Tip: More Help:


Creating Constant Radius Edge Blend from Solid Edges Example

Create an Edge Blend of Radius 0.25 on Solid 7 edges Solid 7.1.5 7.3.6 7.11.1 and 7.3.1.


Creating Chamfer Edge Blend from Solid Edges

This form is used to create a constant angle chamfer on an edge(s) of a solid.


628

Tip: More Help:


Creating Chamfer Edge Blend from Solid Edges Example

Create Chamfers with offset of 0.02 and angle of 45 degrees on Solid 1 edges Solid 1.1.3 1.1.12 1.1.6

1.1.4 1.2.4 and 1.4.4.


Imprinting Solid on Solid

This form is used to imprint solid bodies on solid bodies.


630

Tip: More Help:


Imprint Solid on Solid Example

Imprint Solid Cylinders 2 and 3 onto the faces of Solid Block 1. The Cylinders have been deleted to show

the results of the imprint.


Solid Shell Operation

This form is used to create a void in a solid by shelling the selected faces.


632

Tip: More Help:


Solid Shell Operation Example

Shell solids 1t4 with a wall thickness=0.25 using faces solid 4.1 4.2 3.6 2.1 2.4 2.5 1.4 and 1.2.

Geometry Modeling - Reference Manual Part 2Editing Features

634

Editing Features

Suppressing a Feature

The Edit,Feature,Suppress method displays the list of CAD features associated with the geometry that

can be suppressed from the geometric model.

635Chapter 6: Edit ActionsEditing Features

Unsuppressing a Feature

The Edit,Feature,Unsuppress method displays the list of CAD features associated with the geometry that

can be unsuppressed from the geometric model.


636

Editing Feature Parameters

The Edit,Feature,Parameters method displays the list of CAD features associated with the geometry

whose parameters can be edited to be used to regenerate the geometric model based on the new parameter

values.

637Chapter 6: Edit ActionsEditing Features

Feature Parameter Definition

The Feature Parameter Definition form allows the parameters of a CAD feature to be displayed and

modified for regeneration of a CAD model.


638

Chapter 7: Show Actions


7 Show Actions

� Overview of the Geometry Show Action Methods 640

� Showing Points 642

� Showing Point Distance 644

� Showing Surfaces 669

� Showing Surface Normals 63

� Showing Solids 677

� Showing Coordinate Frames 679

� Showing Planes 681

� Showing Vectors 686

Geometry Modeling - Reference Manual Part 2Overview of the Geometry Show Action Methods

640

Overview of the Geometry Show Action Methods

Figure 7-1


Point • Location • Shows the coordinate value locations for a list of specified

points or vertices. You may enter a reference coordinate system

ID to express the coordinate values within.

• Distance • Shows the distance and the x, y and z offsets between one or

more pairs of points and/or vertices.

• Node • Lists the IDs of the nodes that are located on a specified point

or vertex that is within the Global Model Tolerance value.

Curve • Attributes • Lists the geometric type, length, and starting and ending points

for a list of specified curves or edges.

• Arc • Shows the total number of Arcs in the model, total number of

Arcs in the current group and the geometric modeling

tolerance.

• Angle • Shows the angle between two curves for a list of specified

curves or edges.

• Length Range • Shows the Start and End Point, Length, and Type for a list of

specified curves or edges which are in the Minimum and

Maximum Curve Length Range specified.

• Node • Lists the IDs of the nodes that are located on a specified curve

or edge that is within the Global Model Tolerance value.

Surface • Attributes • Lists the number of vertices and edges associated with each

specified surface or solid face, as well as the area and geometric

type.

• Area Range • Shows the Vertices, Edges, Area, and Type for a list of

specified surfaces or faces which are in the Minimum and

Maximum Surface Area Range specified.

• Node • Lists the IDs of the nodes that are located on a specified surface

or solid face that is within the Global Model Tolerance value.

Solid • Attributes • Lists the number of vertices, surfaces (or faces) associated with

each specified solid, as well as the solid’s volume and

geometric type.

Coord • Attributes • Shows the ID, the xyz coordinate location of the origin and the

type for each specified coordinate frame.

Plane • Attributes

Vector • Attributes

641Chapter 7: Show ActionsOverview of the Geometry Show Action Methods

The Show Action Information Form

When a Show action is executed, Patran will display a spreadsheet form at the bottom of the screen. This

form displays information on the geometric entities that were specified on the Show action form.

Cells on the form that have a dot (.), means there is additional information associated with that cell. If a

cell with the dot is pressed with the cursor, associated information is displayed in the textbox at the

bottom of the form.

Tip: More Help:

• Show Point Distance Information Spreadsheet

• Show Point/Curve Distance Information Spreadsheet

• Show Point/Surface Distance Information Spreadsheet

• Show Curve Angle Information Spreadsheet

Geometry Modeling - Reference Manual Part 2Showing Points

642

Showing Points

Showing Point Locations

Setting Object to Point and Info to Location will show for a list of specified point locations, the

coordinate value locations that are expressed within a specified reference coordinate frame. Also shown

is the element property set assigned to the points. Point locations can be points, vertices, nodes or other


643Chapter 7: Show ActionsShowing Points

Tip: More Help:


• Topology

• Global Model Tolerance & Geometry


• The Show Action Information Form

Geometry Modeling - Reference Manual Part 2Showing Point Distance

644

Showing Point Distance

Showing Point Distance with the Point Option

Show the distance between two points. A multi-page spreadsheet is used to display the distance, direction

cosine and point location data for each point pair.

Tip: More Help:

645Chapter 7: Show ActionsShowing Point Distance


• Topology



Show Point Distance Information Spreadsheet


646

Cell Callback Actions

Showing Point Distance with the Curve Option

Show the distance between point/curve pairs. A multi-page spreadsheet is used to display the distance,

direction cosine and minimum point location data for each point/curve pair.

From Point ID Highlights the point using the secondary highlight color; displays general

information about the point (type, location, etc.) in the textbox.

To Point ID Highlights the point using the secondary highlight color; displays general


Reference CID Highlights both points using the secondary highlight color; displays general

information about the reference frame (type, origin, etc.) in the textbox.

Other columns Highlights both points using the secondary highlight color; displays the long

(un-abbreviated) form of the data in the textbox.


Tip: More Help:


• Topology




648

Show Point/Curve Distance Information Spreadsheet



Showing Point Distance with the Surface Option

Show the distance between point/surface pairs. A multi-page spreadsheet is used to display the distance,

direction cosine and minimum point location data for each point/surface pair.

From Point ID Highlights the point using the secondary highlight color; displays general


From Curve ID Highlights the curve using the secondary highlight color; displays general

information about the curve (type, etc.) in the textbox.

Reference CID Highlights both entities using the secondary highlight color; displays general


Other Columns Highlights both entities using the secondary highlight color; displays the long

(un-abbreviated) form of the data in the textbox; and displays a marker on the

curve where the minimum distance occurs.


650

Tip: More Help:


• Topology




Show Point/Surface Distance Information Spreadsheet


652


Showing Point Distance with the Plane Option

Show the distance between point/Plane pairs. A multi-page spreadsheet is used to display the distance,

direction cosine and minimum point location data for each point/plane pair.

To Point ID Highlights the point using the secondary Highlight color; displays general


From Surface ID Highlights the surface using the secondary Highlight color; displays general

information about the surface (type, etc.) in the textbox.

Reference CID Highlights both entities in the secondary Highlight color; displays general


Other columns Highlights both entities in the secondary highlight color; displays the long (un-

abbreviated) form of the data in the textbox; and displays a marker on the surface

where the minimum distance occurs.


Tip: More Help:


• Topology




654

Show Point/Curve Vector Information Spreadsheet



Showing Point Distance with the Vector Option

Show the distance between point/vector pairs. A multi-page spreadsheet is used to display the distance,

direction cosine and minimum point location data for each point/vector pair.



From Vector ID Highlights the plane using the secondary Highlight color; displays general

information about the vector (type, etc.) in the textbox.



Other columns Highlights both entities in the secondary highlight color; displays the long

(unabbreviated) form of the data in the textbox; and displays a marker on the

surface where the minimum distance occurs.


656

Tip: More Help:


• Topology




Show Point/Curve Distance Information Spreadsheet


658


Showing the Nodes on a Point

Setting Object to Point and Info to Node will show the IDs of the nodes that lie on at specified point

locations that are within the Global Model Tolerance. Point locations can be points, vertices, nodes or

other point locations provided on the Point select menu.



From Plane ID Highlights the plane using the secondary Highlight color; displays general

information about the plane (type, etc.) in the textbox.



Other columns Highlights both entities in the secondary highlight color; displays the long

(unabbreviated) form of the data in the textbox; and displays a marker on the

surface where the minimum distance occurs.


Tip: More Help:


• Topology



Geometry Modeling - Reference Manual Part 2Showing Curves

660

Showing Curves

Showing Curve Attributes

Setting Object to Curve and Info to Attributes will show the geometric type, length, the starting and

ending points, and material and element properties for a list of specified curves or edges.

Tip: More Help:

661Chapter 7: Show ActionsShowing Curves

• Topology


• Types of Geometry in Patran


Showing Curve Arc

Setting Object to Curve and Info to Arc will show the total number of Arcs in the model, total number of

Arcs in the current group and the geometric modeling tolerance.


662

Tip: More Help:

• Topology





Showing Curve Angle

Setting Object to Curve and Info to Angle will show the angle between pairs of curves. The point on each

curve where the angle is calculated from is shown via a primary graphics marker in the graphics marker

color. This is useful if the two curves do not intersect.

Tip: More Help:

• Topology


664



Show Curve Angle Information Spreadsheet



Showing Curve Length Range

Setting Object to Curve and Info to Length Range will show the Start and End Point, Length, and Type

for a list of specified curves or edges which are in the Minimum and Maximum Curve Length Range

specified.

First Curve ID Highlights the curve using the secondary highlight color; displays general


Second Curve ID Highlights the curve using the secondary highlight color; displays general

information about the curve (type, etc.) in the textbox.

Other Columns Highlights both curves in the secondary highlight color; displays the long (un-

abbreviated) form of the data in the textbox; and displays a marker on each curve

at the respective locations where the minimum distance occurs.


666

Tip: More Help:

• Topology





Showing the Nodes on a Curve

Setting the Object to Curve and Info to Node will show the IDs of the nodes that lie on the specified

curves or edges that are within the Global Model Tolerance.

Tip: More Help:

• Topology



668

• Types of Geometry in Patran (p. 19)


669Chapter 7: Show ActionsShowing Surfaces

Showing Surfaces

Showing Surface Attributes

Setting the Object to Surface and Info to Attributes will list the number of vertices and edges associated

with each specified surface or solid face, as well as the its area, geometry type and material and element

properties .

Geometry Modeling - Reference Manual Part 2Showing Surfaces

670

Tip: More Help:


• Topology





Showing Surface Area Range

Setting Object to Surface and Info to Area Range will show the Vertices, Edges, Area, and Type for a list

of specified surfaces or faces which are in the Minimum and Maximum Surface Area Range specified.

Tip: More Help:


• Topology


672

• Global Model Tolerance & Geometry (p. 18)

• Types of Geometry in Patran (p. 19)


Showing the Nodes on a Surface

Setting the Object to Surface and Info to Node will show the IDs of the nodes that lie on the specified

surfaces or solid faces that are within the Global Model Tolerance.


Tip: More Help:

• Topology





674

Showing Surface Normals

Setting the Object to Surface and Info to Normals enables the user to display surface normals of varying

densities on the surface.


676

Tip: More Help:

• Topology




677Chapter 7: Show ActionsShowing Solids

Showing Solids

Showing Solid Attributes

Setting the Object to Solid and Info to Attributes will list the number of vertices and faces associated with

each specified solid, as well as the volume, geometry type and material and element properties .

Tip: More Help:


Geometry Modeling - Reference Manual Part 2Showing Solids

678

• Solids


679Chapter 7: Show ActionsShowing Coordinate Frames

Showing Coordinate Frames

Showing Coordinate Frame Attributes

Setting the Object to Coord and Info to Attributes will list the ID, the coordinate value location of the

coordinate frame’s origin and the coordinate frame type for each specified coordinate frame.

Tip: More Help:


Geometry Modeling - Reference Manual Part 2Showing Coordinate Frames

680

• Coordinate Frame Definitions, 60

• The Show Action Information Form, 641

681Chapter 7: Show ActionsShowing Planes

Showing Planes

Showing Plane Attributes

Setting Object to Plane and Info to Attributes will show for a list of specified plane, displaying the plane

origins and the plane normal that are expressed within a specified reference coordinate frame.

Tip: More Help:

• Showing Point Locations

Geometry Modeling - Reference Manual Part 2Showing Planes

682

Showing Plane Angle

Setting Object to Plane and Info to Angle will show the angle between pairs of planes.


Show Plane Angle/Distance Information Spreadsheet

Geometry Modeling - Reference Manual Part 2Showing Planes

684

Showing Plane Distance

Setting Object to Plane and Info to Distance will show the distance between pairs of planes.

Geometry Modeling - Reference Manual Part 2Showing Vectors

686

Showing Vectors

Showing Vector Attributes

Setting Object to Vector and Info to Attributes will show a list for a specified vector displaying the vector

origins and the vector directions that are expressed within a specified reference coordinate frame.

Tip: More Help:

• Showing Point Locations

Chapter 8: Transform Actions


8 Transform Actions

� Overview of the Transform Methods 688

� Transforming Points, Curves, Surfaces, Solids, Planes and Vectors

691

� Transforming Coordinate Frames 779

Geometry Modeling - Reference Manual Part 2Overview of the Transform Methods

688

Overview of the Transform Methods


Point • Translate • Create points by successively offsetting them through a translation

vector from an existing set of points, nodes or vertices.

• Rotate • Create points by performing a rigid body rotation about a defined

axis from an existing set of points, nodes or vertices.

• Scale • Create points by scaling an existing set of points, nodes or vertices.

• Mirror • Create points by a defined mirror plane of an existing set of points,

nodes or vertices.

• MCoord • Creates points by translating and rotating them from an existing set

of points, nodes, or vertices by referencing coordinate frames.

• Pivot • Creates points from existing points, nodes or vertices by using a

planar rotation defined by three point locations.

• Position • Creates points by translating and rotating existing points, nodes or

vertices, using a transformation defined by three original and three

destination point locations.

• Vsum • Creates points by performing a vector sum of the coordinate

locations of two sets of existing points, nodes or vertices.

• MScale • Creates points by simultaneously moving, scaling, rotating and/or

warping an existing set of points, nodes or vertices.

Curve • Translate • Create curves by successively offsetting them through a translation

vector from an existing set of curves or edges.

• Rotate • Create curves by performing a rigid body rotation about a defined

axis from an existing set of curves or edges.

• Scale • Create curves by scaling an existing set of curves or edges.

• Mirror • Create curves by a defined mirror plane of an existing set of curves

or edges.

• MCoord • Creates curves by translating and rotating them from an existing set

of curves or edges by referencing coordinate frames.

• Pivot • Creates curves from existing curves or edges by using a planar

rotation defined by three point locations.

• Position • Creates curves by translating and rotating existing curves or edges,

using a transformation defined by three original and three

destination point locations.

• Vsum • Creates curves by performing a vector sum of the coordinate

locations of two sets of existing curves or edges.

• MScale • Creates curves by simultaneously moving, scaling, rotating and/or

warping an existing set of curves or edges.

689Chapter 8: Transform ActionsOverview of the Transform Methods

Surface • Translate • Create surfaces by successively offsetting them through a

translation vector from an existing set of surfaces or solid faces.

• Rotate • Create surfaces by performing a rigid body rotation about a defined

axis from an existing set of surfaces or solid faces.

• Scale • Create a set of curves by scaling an existing set of curves or edges.

• Mirror • Create surfaces by a defined mirror plane of an existing set of

surfaces or solid faces.

• MCoord • Creates surfaces by translating and rotating them from an existing

set of surfaces or solid faces by referencing coordinate frames.

• Pivot • Creates surfaces from existing surfaces or solid faces by using a

planar rotation defined by three point locations.

• Position • Creates surfaces by translating and rotating existing surfaces or

solid faces, using a transformation defined by three original and

three destination point locations.

• Vsum • Creates surfaces by performing a vector sum of the coordinate

locations of two sets of existing surfaces or solid faces.

• MScale • Creates surfaces by simultaneously moving, scaling, rotating

and/or warping an existing set of surfaces or solid faces.

Solid • Translate • Create solids by successively offsetting them through a translation

vector from an existing set of solids.

• Rotate • Create solids by performing a rigid body rotation about a defined

axis from an existing set of solids.

• Scale • Create solids by scaling an existing set of solids.

• Mirror • Create solids by a defined mirror plane of an existing set of solids.

• MCoord • Creates solids by translating and rotating them from an existing set

of solids by referencing coordinate frames.

• Pivot • Creates solids from existing solids by using a planar rotation

defined by three point locations.

• Position • Creates solids by translating and rotating existing solids, using a

transformation defined by three original and three destination point

locations.

• Vsum • Creates solids by performing a vector sum of the coordinate

locations of two sets of existing solids.

• MScale • Creates solids by simultaneously moving, scaling, rotating and/or

warping an existing set of solids.


Geometry Modeling - Reference Manual Part 2Overview of the Transform Methods

690

Coord • Translate • Create rectangular, cylindrical or spherical coordinate frames by

successively offsetting them through a translation vector from an

existing set of coordinate frames.

• Rotate • Create rectangular, cylindrical or spherical coordinate frames by

performing a rigid body rotation about a defined axis from an

existing set of coordinate frames.

Plane • Translate • Create solids by successively offsetting them through a translation











locations.

Vector • Translate • Create solids by successively offsetting them through a translation











locations.

• Scale • Create solids by scaling an existing set of solids.


691Chapter 8: Transform ActionsTransforming Points, Curves, Surfaces, Solids, Planes and Vectors

Transforming Points, Curves, Surfaces, Solids, Planes and Vectors

Translating Points, Curves, Surfaces, Solids, Planes and Vectors

The Translate method creates a set of points, curves, surfaces, solids planes or vectors which are

successively offset from each other by a defined Translation Vector <dx dy dz>. Points can be translated

from points, vertices or nodes. Curves can be translated from curves or edges. Surfaces can be translated

from surfaces or solid faces. Solids are translated from solids.

Geometry Modeling - Reference Manual Part 2Transforming Points, Curves, Surfaces, Solids, Planes and Vectors

692


Tip: More Help:



• Translating or Scaling Geometry Using Curvilinear Coordinate Frames

Translating Points Radially

Creates Points 8 through 14 by translating Points 1 through 7, three units radially outward within the

cylindrical coordinate frame, Coord 100. Notice that Curvilinear in Refer. CF is pressed.


694

Translating Points

This example is the same as the previous example, except Cartesian in Refer. CF is pressed instead of

Curvilinear in Refer. CF.


Translating Curves

Creates Curves 2 through 6 by translating Curves 1 three times - two units in the X direction and one unit

in the Y direction within the global rectangular coordinate frame, Coord 0.


696

Translating Curves Radially

Translates Curve 1 three times and radially one unit outward within the cylindrical coordinate frame,

Coord 100. Notice that Curvilinear in Refer. CF is pressed.


Translating Edges

Creates Curve 2 by translating the outside edge of Surface 1, two units radially outward within cylindrical

coordinate frame, Coord 100.


698

Translating Surfaces

Creates Surfaces 2 and 3 by translating Surface 1 two times - one unit in the X direction and two units in

the Y direction within the rectangular coordinate frame, Coord 10.


Translating Surfaces Radially

Creates Surfaces 2 through 4 by translating Surface 1 three times and one unit radially outward within

the cylindrical coordinate frame, Coord 100.


700

Translating Solid Faces

Creates Surfaces 1 through 4 by translating the top faces of Solids 1 through 4, 0.5 units radially outward

within the spherical coordinate frame, Coord 20. Notice that Curvilinear in Refer. CF is pressed.


Translating Solids

Translates Solids 1 through 4, 1.5 units in the X direction and 1.5 units in the Y direction, within the

global rectangular coordinate frame, Coord 0. Notice that Delete Original Solids is pressed and Solids

1:4 are deleted.


702

Translating Solids

Creates Solid 2 by translating Solid 1, 90 degrees within the cylindrical coordinate frame, Coord 1.

Notice that Curvilinear in Refer. CF is pressed.


Translating Planes

Translates Plane 1 2 units in the Z direction with the global rectangular coordinate frame, Coord 0. Note

that Delete Original Plane is not pressed and Plane 1 is kept.


704

Translating Vectors

Translates Vector 1 2 units in the X direction with the global rectangular coordinate frame, Coord 0.

Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Rotating Points, Curves, Surfaces, Solids, Planes and Vectors

Creates a set of points, curves, surfaces, solids, planes or vectors by a rigid body rotation about a defined

axis from an existing set of entities. Points can be rotated from other points, vertices or nodes. Curves

can be rotated from other curves or edges. Surfaces can be rotated from other surfaces or solid faces.

Solids are rotated from other solids.


706


Tip: More Help:



Rotating Points and Nodes

Creates Points 7 through 14 from Point 1 and Node 10 by rotating them six times, 30 degrees about the

global rectangular coordinate frame’s Z axis, Coord 0.3, with an offset angle of 60 degrees. (Coord 0.3

can be cursor defined by using the Axis select menu icon listed below and cursor selecting Coord 0.)


708

Rotating Curves

Creates Curves 2 through 7 by rotating Curve 1 six times, 30 degrees about the axis defined by {[0 0 0][0

0 1]}. Notice that the axis definition is equivalent to Coord 0.3 from the previous example.


Rotating From An Edge

This example is the same as the previous example, except that Curves 1 through 6 are rotated from an

edge of Surface 1.


710

Rotating Surfaces

Creates Surfaces 4 through 18 by rotating from Surfaces 1, 2 and 3, five times, 30 degrees each about the

axis defined by Points 4 and 1. The axis is defined by cursor selecting the points using the Axis select

menu icon listed below.


Rotating From Solid Faces

This example is the same as the previous example, except that Surfaces 1 through 16 are rotated from the

outside faces of Solid 1.


712

Rotating Solids

Creates Solids 2 through 4 by rotating from Solid 1, three times, 90 degrees each about the global Z axis,

Coord 0.3. Coord 0.3 is cursor defined by using the Axis select menu icon listed below.


Rotating Planes

Rotates Plane 1 90 degrees around the Y Axis in the global rectangular coordinate frame, Coord 0. Notice

that Delete Original Plane is not pressed and Plane 1 is kept.


714

Rotating Vectors

Rotates Vector 1 90 degrees around the Z Axis in the global rectangular coordinate frame, Coord 0.

Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Scaling Points, Curves, Surfaces, Solids and Vectors

The Scale method creates a set of points, curves, surfaces, solids or vectors by scaling an existing set of

entities. Points can be scaled from other points, vertices or nodes. Curves can be scaled from other curves

or edges. Surfaces can be scaled from other surfaces or solid faces. Solids are scaled from other solids.


716


Tip: More Help:



• Translating or Scaling Geometry Using Curvilinear Coordinate Frames

Scaling Points and Nodes

Creates Points 6 through 9 by scaling them from Points 1, 2, 5 and Node 100 two times along the global

X and Y axes, with Point 4 as the origin of scaling.


718

Scaling Points Radially

Creates Points 25 through 44 by scaling them from the points on the outside edge of Surfaces 1 through

4, two times radially within the cylindrical coordinate frame, Coord 100. Notice that Curvilinear in Refer.

CF and Delete Original Points are pressed.


Scaling Curves

Creates Curve 2 by scaling them from Curve 1, 1.5 times along the X axis of rectangular coordinate

frame, Coord 20. Notice that Delete Original Curves is pressed and Curve 1 is deleted.


720

Scaling From An Edge

Creates Curves 1 through 4 by scaling them from the outside edges of Surfaces 1 through 4, 1.5 times

radially outward within the cylindrical coordinate frame, Coord 20. Notice that Curvilinear in Refer. CF

is pressed.


Scaling Surfaces

Creates Surfaces 5 through 8 by scaling Surfaces 1 through 4 1.5 times along the radial axis of cylindrical

coordinate frame, Coord 20. Notice that Cartesian in Refer. CF and Delete Original Surfaces are pressed.


722

Scaling Surfaces Radially

This example is the same as the previous example, except that Curvilinear in Refer. CF is selected instead

of Cartesian in Refer. CF.


Scaling From Solid Faces

Creates Surface 1 by scaling it from the top face of Solid 1, 1.5 times in the X, Y and Z directions of the

global rectangular coordinate frame, Coord 0.


724

Scaling From Solids

Creates Solids 5 through 8 by scaling them from Solids 1 through 4, two times in the X and Y directions

of the global rectangular coordinate frame, Coord 0.


Scaling From Vectors

Scales Vector 1 with a scale factor of 2 in the X direction in the global rectangular coordinate frame,

Coord 0. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


726

Mirroring Points, Curves, Surfaces, Solids, Planes and Vectors

Creates a set of points, curves, surfaces, solids, planes or vectors by a defined mirror plane of an existing

set of entities. Points can be mirrored from other points, nodes or vertices. Curves can be mirrored from

other curves or edges. Surfaces can be mirrored from other surfaces or solid faces. Solids are mirrored

from other solids.


Tip: More Help:



Mirroring Points and Nodes

Creates Points 7 through 12 by mirroring them from Points 1 through 6 and Node 100, about the mirror

plane whose normal is the global X axis, Coord 0.1. Coord 0.1 can be cursor defined by using the Axis

select menu icon listed below.


728

Mirroring Curves

Creates Curves 3 and 4 by mirroring them from Curves 1 and 2 about the plane whose normal is the

global Y axis, Coord 0.2, and with an offset of Y=-1.


Mirroring From Edges

Creates Curves 1 through 8 by mirroring them from the inner and outer edges of Surfaces 5 through 8

about the plane whose normal is rectangular coordinate frame 1’s Y axis, Coord 1.2.


730

Mirroring Surfaces

This example is similar to the previous example, except that Surfaces 1 through 4 are mirrored from

Surfaces 5 through 8.


Mirroring Solids

Creates Solid 2 by mirroring Solid 1 about the plane whose normal is defined by {[0 0 0][1 0 0]}. Notice

that the mirror plane normal definition is the same as entering the global X axis, Coord 0.1.


732

Mirroring Planes

Mirrors Plane 1 against the X-Y plane and with an offset of 1 unit in the Z direction in the global

rectangular coordinate frame, Coord 0. Notice that Delete Original Plane is not pressed and Plane 1 is

kept. Also, the Reverse Plane is not pressed and Plane 2 is not reversed.


Mirroring Vectors

Mirrors Vector 1 against the X-Y plane and with an offset of 1 unit in the Z direction in the global

rectangular coordinate frame, Coord 0. Notice that Delete Original Vector is not pressed and Vector 1 is

kept. Also, the Reverse Vector is not pressed and Vector 2 is not reversed.


734

Moving Points, Curves, Surfaces, Solids, Planes and Vectors by Coordinate Frame Reference (MCoord Method)

Translates and rotates a new set of points, curves, surfaces, solids, planes or vectors from an existing set

of entities by referencing coordinate frames. The new entities’ local position with respect to the To

Coordinate Frame is the same as the local position of the original entities with respect to the From

Coordinate Frame. Points can be moved from other points, nodes or vertices. Curves can be moved from

other curves or edges. Surfaces can be moved from other surfaces or solid faces. Solids are moved from

other solids.


Tip: More Help:



Moving Points and Nodes

Creates Points 7 through 12 from Points 1, 3, 4, 5, 6 and Node 100 by moving them from the global

rectangular coordinate frame, Coord 0, to the rectangular coordinate frame, Coord 100.


736

Moving Curves

Creates Curves 7 through 12 by moving Curves 1 through 6 from cylindrical coordinate frame, Coord

200 to cylindrical coordinate frame, Coord 300.


Moving From Edges

This example is similar to the previous example, except that Curves 1 through 8 are moved from the

outside edges of Surfaces 1 through 4, from Coord 200 to Coord 300.


738

Moving Surfaces

Creates Surfaces 5 through 8 by moving from Surfaces 1 through 4 from cylindrical coordinate frame,

Coord 200, to cylindrical coordinate frame, Coord 300.


Moving Solids

Creates Solids 5 through 8 by moving Solids 1 through 4 from the global coordinate frame, Coord 0, to

the rectangular coordinate frame, Coord 1.


740

Moving Planes

Moves Plane 1 from the rectangular coordinate frame, Coord 0, to the rectangular coordinate frame,

Coord 1. Notice that Delete Original Plane is not pressed and Plane 1 is kept.


Moving Vectors

Moves Vector 1 from the rectangular coordinate frame, Coord 0, to the rectangular coordinate frame,

Coord 1. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


742

Pivoting Points, Curves, Surfaces, Solids, Planes and Vectors

Creates points, curves, surfaces, solids, planes and vectors by using a planar rotation defined by a

specified Pivot Point about which the entity will be rotated, and a Starting Point and Ending Point for

the rotation. Points can be pivoted from other points, nodes or vertices. Curves can be pivoted from other

curves or edges. Surfaces can be pivoted from other surfaces or solid faces. Solids are pivoted from other

solids.


Tip: More Help:



744


Pivoting Points

Creates Point 4 from Point 3 by pivoting at the global origin, [0 0 0], from Node 100 to Point 2.


Pivoting Curves

Creates Curves 9 through 15 from Curves 1 through 6 by pivoting them at Point 12, from Point 14 to

Point 13. (Curves 7 and 8 are for illustration and are not used for the pivot.)


746

Pivoting From Edges

Creates Curves 9 through 16 by pivoting from the outside edges of Surfaces 1 through 4, at Point 12, from

Point 14 to Point 13. Curves 7 and 8 are for illustration and are not used for the pivot.


Pivoting Surfaces

This example is similar to the previous example, except that Surfaces 1 through 4 are pivoted to create

Surfaces 5 through 8. Curves 7 and 8 are for illustration and are not used for the pivot.


748

Pivoting Solids

Creates Solid 2 by pivoting from Solid 1 at Point 1, from Point 2 to Point 3. Curves 1 and 2 are for

illustration and are not used for the pivot.


Pivoting Planes

Pivots Plane 1 using the 3 pivoting points, Point 1 through 3. Notice that Delete Original Plane is not

pressed and Plane 1 is kept.


750

Pivoting Vectors

Pivots Vector 1 using the 3 pivoting points, Point 1 through 3. Notice that Delete Original Vector is not

pressed and Vector 1 is kept.


Positioning Points, Curves, Surfaces, Solids, Planes and Vectors

Creates points, curves, surfaces, solids, planes and vectors by translating and rotating an existing set of

entities using a transformation defined by three original point locations to three destination point

locations.


752

The original points and destination points need not match exactly; however, if either the original point

locations or the destination point locations lie in a straight line, the transformation cannot be performed.

Points can be repositioned from other points, nodes or vertices. Curves can be repositioned from other

curves or edges. Surfaces can be repositioned from other surfaces or solid faces. Solids are repositioned

from other solids.


754

Tip: More Help:

• Select Menu (p. 33) in the MD Patran Reference Manual, Part 1: Basic Functions

• Coordinate Frame Definitions (p. 60)

Positioning Points

Creates Points 9 through 12 from Points 1through 4 by repositioning them based on the original and

destination point locations listed on the form.


Positioning Curves

Creates Curves 25 through 32 by repositioning Curves 13 through 24 from Points 9, 13 and 12, to

destination Points 2, 6 and 3. Notice that Delete Original Curves is pressed and Curves 13 through 24 are

deleted.


756

Positioning From Edges

This example is similar to the previous example, except that the edges of Solid 1 are repositioned to the

new location to create Curves 13 through 20.


Positioning Surfaces

Creates Surface 5 from Surface 4 by positioning it from Points 8, 9 and 11 to the destination Points 7, 2

and 3.


758

Positioning Solids

Creates Solid 3 by repositioning it from Solid 2, based on the original and destination points listed on the

form. Notice that Delete Original Solids is pressed and Solid 2 is deleted.


Positioning Planes

Positions Plane 1 from where defined by the position Point 1 through 3, to where defined by the position

Point 4 through 6. Notice that Delete Original Plane is not pressed and Plane 1 is kept.


760

Positioning Vectors

Positions Vector 1 from where defined by the position Point 1 through 3, to where defined by the position

Point 4 through 6. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Vector Summing (VSum) Points, Curves, Surfaces and Solids

Creates points, curves, surfaces or solids by performing a vector sum of the coordinate locations of two

sets of existing entities to form one set of new entities. Points can be created from the summation of other

points, nodes or vertices. Curves can be created from the summation of other curves or edges. Surfaces

can be created from the summation of other surfaces or solid faces. Solids are created from the

summation of other solids.


762


Tip: More Help:



Vector Summing Points

Creates Points 7, 8 and 9 by summing the vectors drawn from the origin, [0 0 0], to Points 1 and 4, 2 and

5 and 3 and 6. The “After” picture below has the vectors drawn to Points 2 and 5 to show how Point 8

was created.


764

Vector Summing Points

This example is the same as the previous example, except that a Multiplication Factor 2 is increased from

“1 1 1” to “2 2 2”.


Vector Summing Curves

Creates Curves 20 through 27 which are summed between Curves 12 through 19 and Curves 1 through

4. Notice that in order to create the spiral, Curve 1:4 must be entered twice in the Curve 2 List to match

the eight curves listed in the Curve 1 List.


766

Vector Summing Curves

Creates Curve 3 by summing Curves 1 and 2. Notice that the multiplication factors of “.5 .5 .5” are

entered for both Multiplication Factors 1 and 2 and Curve 3 becomes the “average” of Curves 1 and 2 in

length and in curvature.


Vector Summing Surfaces

This example creates Surface 4 from vector summing the coordinate locations of Surfaces 1 and 3.


768

Vector Summing With Solid Faces

This example is similar to the previous example, except that Surface 4 is created by vector summing the

coordinate locations of the outside face of Solid 1 and Surface 3.


Vector Summing Solids

Creates Solid 3 by vector summing the coordinate locations of Solids 1 and 2.


770

Moving and Scaling (MScale) Points, Curves, Surfaces and Solids

Creates a set of points, curves, surfaces and solids by simultaneously moving, scaling, rotating and/or

warping an existing set of entities. Points can be moved and scaled from other points, nodes or vertices.


Curves can be moved and scaled from other curves or edges. Surfaces can be moved and scaled from

other surfaces or solid faces. Solids are moved and scaled from other solids.


772


Tip: More Help:



Translating and Mirroring Points

Creates Points 8 through 13 by simultaneously translating and mirroring Points 1 though 7, two units in

the global X direction and mirroring about the global YZ plane.


774

Mirroring and Scaling Curves

Creates Curves 7 through 12 by simultaneously scaling and mirroring Curves 1 through 6. The curves are

scaled two times in the global Y direction and they are mirrored about the global XZ plane.


Mirroring and Scaling Curves

This example is similar to the previous example, except that the curves are mirrored and scaled within

the rectangular coordinate frame, Coord 100.


776

Translating and Rotating Surfaces

Creates Surfaces 5 through 8 from Surfaces 1 through 4 by translating them 10 units in the global Z

direction and rotating them -120 degrees about the global X axis.


Translating, Mirroring and Scaling Solids

This example simultaneously translates, mirrors and scales Solids 5 through 8 from Solids 1 through 4,

by translating them 1.57 units in the global X direction and 1.0 unit in the global Y direction; mirroring

them about the global XZ plane; and scaling them .5 in the X direction and .5 in the Y direction.


778

779Chapter 8: Transform ActionsTransforming Coordinate Frames

Transforming Coordinate Frames

Translating Coordinate Frames

Creates coordinate frames which are successively offset from each other by the Translation Vector <dx

dy dz>, starting from an existing set of specified coordinate frames.

Tip: More Help:

Geometry Modeling - Reference Manual Part 2Transforming Coordinate Frames

780




Creates the rectangular coordinate frame, Coord 2, from coordinate frame, Coord 1, by translating it two

units in the global X direction.



Creates the rectangular coordinate frame, Coord 2, from coordinate frame, Coord 1, by translating it

through a translation vector defined by Points 1 and 2, using the Vector select menu icon listed below.


782

Rotating Coordinate Frames

Creates a set of coordinate frames which are formed from a specified set of existing coordinate frames

by a rigid body rotation about a defined axis.


784

Tip: More Help:




Creates the rectangular coordinate frame, Coord 2, from coordinate frame, Coord 1, by rotating it 45

degrees about the axis listed on the form.



Creates the cylindrical coordinate frame, Coord 200, from cylindrical coordinate frame, Coord 100, by

rotating it 90 degrees about Coord 100’s Z axis, Coord 100.3, using the Axis select menu icon listed

below. Notice that Delete Original Coords is pressed and Coord 100 is deleted.


786

Chapter 9: Verify Actions


9 Verify Actions

� Verify Actions 787

Geometry Modeling - Reference Manual Part 2Verify Action

788

Verify Action

Verifying Surface Boundaries

The Boundary method for surfaces will allow you to plot the free or non-manifold edges for a list of

specified surfaces or solid faces. A free edge is any edge that is not shared by at least one other surface

or solid face. A non-manifold edge is shared by more than two surfaces or solid faces. Non-manifold

often indicates a geometry which is not manufacturable; it may be alright for surface models or on shared

solid faces, but is illegal in a B-rep solid.This method is recommended for verifying cracks in the model,

or more specifically in a surface set to be used in creating a B-rep solid.

789Chapter 9: Verify ActionsVerify Action


790

Verifying Surfaces for B-reps

The B-rep method for surfaces will allow you to plot the free or non-manifold edges for a list of specified

surfaces or solid faces. A free edge is any edge that is not shared by at least one other surface or solid

face. A non-manifold edge is shared by more than two surfaces or solid faces. Non-manifold often

indicates a geometry which is not manufacturable; it may be alright for surface models or on shared solid

faces, but is illegal in a B-rep solid.This method is recommended for verifying cracks in the model, or

more specifically in a surface set to be used in creating a B-rep solid.


Update Graphics Subordinate Form

The Update Graphics subordinate form is displayed when the Update Graphics button is pressed on the

Verify/Surface/Boundaries form. This subordinate form allows you to erase or plot in the current

viewport, groups of congruent or incongruent surfaces.

This form is useful for checking for surface cracks, topologically incongruent surfaces, or non-manifold

edges shared by more than two surfaces. MSC.Software Corporation suggests you use either the

Edit/Surface/Edge Match form (see Matching Surface Edges) or the Create/Surface/Match form (see

Matching Adjacent Surfaces) to correct any incongruent surfaces that have a gap between them.


792

Tip: More Help:


• Building a Congruent Model

• Group>Create (p. 263) in the Patran Reference Manual

Verify - Surface (Duplicates)

Surfaces in the entire model are checked for being duplicate.


794

Chapter 10: Associate Actions


10 Associate Actions

� Overview of the Associate Action 796

Geometry Modeling - Reference Manual Part 2Overview of the Associate Action

796

Overview of the Associate Action

The Associate action causes a geometric entity to become embedded on another geometric entity.

Surfaces with associated geometry will not get trimmed (i.e., a four sided iso parametric patch will

remain so even after associations are made to the patch).

Associations allow the mesher to create nodes on or along the associated geometry.

Loads or boundary conditions may be applied to associated geometries.

Mesh seeds can be placed on the associated geometry.

The nodes lying on the associated geometry have the associated geometry as topological associations

(i.e., nodes that lie on a curve associated to a surface will have their topological associations to the curve

rather than with the surface).

Associations are marked by filled blue triangles for points and filled yellow triangles for curves.

Table 10-1 Geometry Associate Action Objects and Descriptions


• Point Curve Associate point to a curve.

Surface Associate point to a surface.

• Curve Curve Associate curve to a curve.

Surface Associate curve to a surface.

Important:The iso-mesher will not generate meshes that conform to hard geometries, if the hard

geometries lie interior to the surface. The iso-mesher ignores the interior hard geometries

to mesh the surface.

797Chapter 10: Associate ActionsOverview of the Associate Action

Associating Point Object

Figure 10-1


798

Figure 10-2

799Chapter 10: Associate ActionsOverview of the Associate Action

Associating Curve Object

Figure 10-3


800

Figure 10-4

Chapter 11: Disassociate Actions


11 Disassociate Actions

� Overview of the Disassociate Action Methods 802

Geometry Modeling - Reference Manual Part 2Overview of the Disassociate Action Methods

802

Overview of the Disassociate Action Methods

The disassociate action causes the association records to be deleted. All other information such as mesh

seed and loads and boundary conditions will be preserved on the disassociated entity, if there are any.

The disassociate action causes the filled blue triangles and yellow triangles that mark the association of

points and curves respectively, to be removed.

803Chapter 11: Disassociate ActionsOverview of the Disassociate Action Methods

Disassociating Points

Figure 11-1

Object Description

• Point • Remove all point associations.

• Curve • Remove all curve associations.

• Surface • Remove all surface associations.


804

Disassociating Curves

Disassociating Surfaces

805Chapter 11: Disassociate ActionsOverview of the Disassociate Action Methods

Figure 11-2


806

Chapter 12: The Renumber Action... Renumbering Geometry


12 The Renumber Action...

Renumbering Geometry

� Renumber Forms 809

Geometry Modeling - Reference Manual Part 2Introduction

808

Introduction

Most often, ID numbers (IDs) for geometric entities are chosen and assigned automatically. The

Renumber Action permits the IDs of points, curves, surfaces, solids, planes, or vectors to be changed.

This capability is useful to:

• Offset the IDs of a specific list of entities.

• Renumber the IDs of all existing entities within a specified range.

• Compact the IDs of an entity type sequentially from 1 to N.

IDs must be positive integers. Duplicate IDs are not permitted in the List of New IDs, or in the selected

Entity List (old IDs). A Starting ID or a List of New IDs may be entered in the input databox. If a

geometric entity outside the list of entities being renumbered is using the new ID, the renumber process

will print a warning message stating which ID is already in use and proceed to use the next highest

avaliable ID since each entity must have a unique ID. The default is to renumber all the existing entities

beginning with the minimum ID through the maximum ID consecutively starting with 1.

If only one ID is entered, it is assumed to be the starting ID. The entities will be renumbered

consecutively beginning with the starting ID.

If more than one ID is entered and there are fewer IDs in the List of New IDs than there are valid entities

in the selected Entity List, renumbering will use the IDs provided and when the list is exhausted, the next

highest available ID will be used thereafter to complete the renumbering. The List of New IDs may

contain a # signifying to use the maximum ID + 1 as the Starting ID. However, the list may have more

IDs than needed.

The IDs in the selected Entity List may contain a #. The value of the maximum existing ID is

automatically substituted for the #. There may be gaps of nonexisting entities in the list but there must be

at least one valid entity ID in order for renumbering to take place.

A percent complete form shows the status of the renumber process. When renumbering is complete, a

report appears in the command line indicating the number of entities renumbered and their new IDs. The

renumber process may be halted at any time by pressing the Abort button and the old IDs will be restored.

809Chapter 12: The Renumber Action... Renumbering GeometryRenumber Forms

Renumber Forms

When Renumber is the selected Action the following options are available.

Object Description

• Point • The point menu selection provides the capability to renumber or

change the IDS of points.

• Curve • The curve menu selection provides the capability to renumber or

change the IDs of curves.

• Surface • The surface menu selection provides the capability to renumber or

change the IDs of surfaces.

• Solid • The solid menu selection provides the capability to renumber or

change the IDs of solids.

• Plane • The plane menu selection provides the capability to renumber or

change the IDs of planes.

• Vector • The vector menu selection provides the capability to renumber or

change the IDs of vectors.

Geometry Modeling - Reference Manual Part 2Renumber Forms

810

Renumber Geometry

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Index

Numerics3 point method

overview, 64

Aaccuracy, 2

any geometry entity

delete action, 463

arc center

point, 82

arc3point method

curve, 130

axis method

overview, 64

Bbi-parametric surface, 20

blend method

curve, 484

solid, 607

surface, 538

body, 11

break method

curve, 474, 478, 482

example, 32

solid, 591, 595, 600, 602, 604

surface, 520, 524, 528, 532, 534

B-rep method, 41

B-rep solid, 8, 20, 24, 41

exterior shell, 41

shell, 24

building a B-rep solid, 41

building a congruent model, 31

example, 32

building a degenerate solid, 43

building a degenerate surface, 42

building optimal surfaces, 33

CCAD access modules, 47

CAD user file, 2, 20, 46, 47

capabilities, 2

Cartesian in Refer. CF button, 67

CATIA, 2, 47

chain method

curve, 133

chained curve, 21, 22

conic method

curve, 135

connectivity

curve, 16

definition, 16

modifying, 18

solid, 17

surface, 17

coordinate frame

attributes

show action, 679

create method overview, 64

definitions, 60

delete action, 466

rotate method, 782

translate method, 779

create action, 27

overview, 72


812

curve

arc3point method, 130

blend method, 484

break method, 474, 478, 482

chain method, 133

conic method, 135

delete action, 464

disasemble method, 487

extend method, 490, 496, 499, 501

extract method, 139, 143

fillet method, 145

fit method, 149

intersect method, 151, 155

manifold method, 161

mcoord method, 734

merge method, 504

mirror method, 726

mscale method, 770

offset method constant, 171

offset method variable, 173

pivot method, 742

point method, 120, 122, 125

position method, 751

refit method, 508

reverse method, 510

rotate method, 705

scale method, 715


trim method, 513, 516

vsum method, 761

XYZ method, 199

curve 4 point parametric positions subordinate

form, 129

curve angle

show action, 663

curve arc

show action, 661

curve attributes

show action, 660

curve length range

show action, 665

curve method, 42

curvilinear coordinate frame, 67

examples using translate and scale, 67

scale method, 67


Curvilinear in Refer. CF button, 67

cylindrical coordinate frame

definition, 61

DDassault Systemes, 2, 47

Decompose method, 38

decomposing trimmed surfaces, 38

example, 39

default colors, 20, 21, 22, 24

degenerate surfaces and solids, 42

delete action

any geometry entity, 463

coordinate frame, 466

curve, 464

overview, 462

plane, 464

point, 464

solid, 464

surface, 464

vector, 464

DGA, 2, 47

Direct Geometry Access, 2, 47

disasemble method

curve, 487

surface, 541

disassemble method

solid, 610

display lines, 34, 41

Eedge, 11

edge match method, 32

closing gaps, 15

surface, 548, 551

edge method, 42

edge refit method

surface, 568

edit action, 27

overview, 470

EDS/Unigraphics, 2, 47

element connectivity, 35

element properties, 2

equivalence method

point, 472

813INDEX

euler method

overview, 65

examples

arc3point curve, 131, 132

ArcCenter point, 83

blend

curve, 485, 486

solid, 608, 609

surface, 540

break

curve, 475, 476, 477, 480, 481

solid, 592, 593, 594, 597, 598, 599,

601, 605, 606

surface, 521, 522, 523, 525, 529, 530,

531, 533, 536, 537

chain curve, 134

conic curve, 137, 138

disassemble

curve, 489

surface, 543

edge match surface, 550, 552

equivalencene point, 472

extend curve, 493, 494, 495, 498, 501, 503

extend surface, 554, 556, 558, 560, 563,

565, 567

extract

curve, 140, 141, 142, 144

point, 85, 86

point from surface, 88

point from surface diagonal, 90

point from surface parametric, 92

fillet curve, 147, 148

fit curve, 150

interpolate point, 95, 96, 99

interpolate vector, 435

intersect

curve, 152, 153, 154, 156, 157

point at edge, 101

point with curve and plane, 105

point with two curves, 102, 103, 104

point with vector and curve, 106, 107

point with vector and plane, 109

point with vector and surface, 108

manifold curve, 163

mcoord

curve, 736, 737

plane, 740

point, 735

solid, 739

surface, 738

vector, 741

merge curve, 506, 507, 512, 515, 518

mirror

curve, 728, 729

plane, 732

point, 727

solid, 731, 733

surface, 730

mscale


814

curve, 774, 775

point, 773

solid, 777

surface, 776

offset curve, 172, 175

offset point, 111

offset surface, 272

pierce point, 113, 114

pivot

curve, 745, 746

plane, 749

point, 744

solid, 748

surface, 747

vector, 750

point curve, 121, 123, 124, 127, 128

position

curve, 755, 756

point, 754

solid, 758, 759, 760

surface, 757

project point, 117, 118, 119

reverse

curve, 512

solid, 618

surface, 571

rotate

coordinate frame, 784, 785

curve, 708, 709

plane, 713

point, 707

solid, 712

surface, 710, 711

vectors, 714

scale

curve, 719, 720

point, 717, 718

solid, 724

surface, 721, 722, 723

vector, 725

sew surface, 573

translate

coordinate frame, 780, 781

curve, 695, 696, 697

plane, 703

point, 693, 694

solid, 701, 702

surface, 698, 699, 700

vector, 704

trim curve, 514

vsum

curve, 765, 766

point, 763, 764

solid, 769

surface, 767, 768

XYZ

curve, 200

point, 79, 80, 81

solid, 202

surface, 201

extend method

curve, 490, 496, 499, 501

surface, 553, 555, 557, 559, 561, 564, 566

extract method

curve, 139, 143

multiple points, 89, 91

point, 84

single point, 87

Fface, 11

face method, 43

field function, 4, 18

fillet method

curve, 145

fit method

curve, 149

Ggeneral trimmed surface, 21

geometry types, 20

global coordinate frame, 60

global model tolerance, 19

surface gaps, 14

grid, 25

Hhyperpatch, 25

IIGES, 3, 20, 25, 46

815INDEX

interpolate method

point, 94, 97

vector, 434

intersect method

curve, 151, 155

intersect parameters subordinate form, 158

point, 100

intersect parameters subordinate form, 158

IsoMesh, 19, 24, 38

Lline, 25

load/BC, 2

loads/BC, 2

Mmanifold method

curve, 161

match method

closing gaps, 15

mathematical representation, 2

mcoord method

curve, 734

plane, 734

point, 734

solid, 734

surface, 734

vector, 734

merge method

curve, 504

refit, 508

meshing, 13

mirror method

curve, 726

plane, 726

point, 726

solid, 726

surface, 726

vector, 726

MSC.Patran CATIA, 47

MSC.Patran ProENGINEER, 47, 54

.geo intermediate file, 56

executing from MSC.Patran, 55

executing from Pro/ENGINEER, 55

MSC.Patran Unigraphics, 47

features, 47

global model tolerance, 48

user tips, 48

mscale method

curve, 770

point, 770

solid, 770

surface, 770

multiple points

extract method, 89, 91

Nnative geometry, 3

neutral file, 3, 25, 46, 57

nodes, 810

renumber, 810

nodes on curve

show action, 667

nodes on point

show action, 658

nodes on surface

show action, 672

normal method

overview, 65

Ooffset method

constant curve, 171

point, 110

surface, 271

variable curve, 173

Pp3_proe, 55

parameterization

B-rep solid, 8

curve, 5

definition, 4

point, 4

solid, 8

surface, 6

trimmed surface, 7

parameterized geometry, 3


816

parametric axes, 16

plotting, 18

parametric cubic equation, 25

parametric cubic geometry, 57

definition, 25

limitations, 26

recommendations, 25, 26

subtended arcs, 26

parametric curve, 20

Parametric Technology, 2, 47

Parasolid

tips for accessing, 49

patch, 25

PATRAN 2 Convention, 28, 29

PATRAN 2 Convention button, 25, 28

Paver, 38

pentahedron, 43

pierce method

point, 112

pivot method

curve, 742

plane, 742

point, 742

solid, 742

surface, 742

vector, 742

plane

mcoord method, 734

mirror method, 726

pivot method, 742


rotate method, 705


plane angle

show action, 682

plane distance

show action, 684

point, 20

delete action, 464

equivalence method, 472

extract method, 84

interpolate method, 94, 97

intersect method, 100

mcoord method, 734

mirror method, 726

mscale method, 770

offset method, 110

pierce method, 112

pivot method, 742


project method, 115

rotate method, 705

scale method, 715


vsum method, 761

XYZ method, 78

point distance

show action, 644

point location

show action, 642

point method

curve, 120, 122, 125

curve 4 point parametric positions

subordinate form, 129

position method

curve, 751

plane, 751

point, 751

solid, 751

surface, 751

vector, 751

pressure load, 4, 18, 35

Pro/ENGINEER, 2, 47

project method

point, 115

Rrectangular coordinate frame

definition, 60

refit method

solid, 613

renumber

action, 809

817INDEX

reverse method, 18, 34

curve, 510

solid, 352, 353, 618

surface, 570

rotate method


curve, 705

point, 705

solid, 705

surface, 705

Sscale method

curve, 715

point, 715

solid, 715

surface, 715

vector, 715

sew method

surface, 572

show action

coordinate frame attributes, 679

curve angle, 663

curve arc, 661

curve attributes, 660

length range, 665

nodes on curve, 667

nodes on point, 658

nodes on surface, 672

overview, 640

plane angle, 682

plane distance, 684

point distance, 644

point location, 642

showing plane attributes, 681

showing vector attributes, 686

solid attributes, 677

surface area range, 671

surface attributes, 669

surface normals, 674

show action information form, 641

simply trimmed surface, 22

single point

extract method, 87

solid

blend method, 607

break method, 591, 595, 600, 602, 604

delete action, 464

disassemble method, 610

mcoord method, 734

mirror method, 726

mscale method, 770

pivot method, 742


refit method, 613

reverse method, 352, 353, 618

rotate method, 705

scale method, 715


vsum method, 761

XYZ method, 199

solid attributes

show action, 677

solids

type of, 24

spherical coordinate frame

definition, 62

subtract method

surface, 574

suface normals

show action, 674


818

surface

blend method, 538

break method, 520, 524, 528, 532, 534

delete action, 464

disassemble method, 541

edge match method, 548, 551

extend method, 553, 555, 557, 559, 561,

564, 566

mcoord method, 734

mirror method, 726

mscale method, 770

offset method, 271

pivot method, 742


refit method, 568

reverse method, 570

rotate method, 705

scale method, 715

sew method, 572

sharp corners, 34

subtract method, 574

top and bottom locations, 35


vsum method, 761

XYZ method, 199

surface area range

show action, 671

surface attributes

show action, 669

surface boundaries

verify action, 788

surface method, 43

surface normals, 18, 34, 41

example of aligning, 35

TTetMesh, 24, 25, 41

tetrahedron, 43

topologic entities

edge, 11

face, 11

vertex, 11

topological congruency, 31

definition, 13

gaps, 14

topology

definition, 10

ID assignment, 12, 13, 18

transform action

overview, 688

translate method


curve, 691

plane, 691

point, 691

solid, 691

surface, 691

vector, 691

trim method

curve, 513, 516

trimmed surface, 20

decomposing, 38

default colors, 20

definition, 20

general trimmed, 21

parent surface, 20

simply trimmed, 22

tri-parametric solid, 8, 20, 24

types of geometry, 27

curves, 28

solids, 29

surfaces, 29

Uupdate graphics subordinate form, 791

Vvector

interpolate method, 434

mcoord method, 734

mirror method, 726

pivot method, 742


rotate method, 705

scale method, 715


verify action

surface boundaries, 788

update graphics subordinate form, 791

vertex, 11

819INDEX

volume solid, 20

vsum method

curve, 761

point, 761

solid, 761

surface, 761

Wwedge solid, 43

XXYZ method

curve, 199

point, 78

solid, 199

surface, 199


820

Patran 2008 r1 Reference Manual Part 2: Geometry Modeling

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Transcript of Patran 2008 r1 Reference Manual Part 2: Geometry Modeling