Transcript of Introduction
Slide 1Using a computer to make vector-based drawings.
Using a computer controlled machine to produce actual parts from a
CAD drawing.
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2. Understand the various computer hardware devices
3. Understand the various software used in CAD and the functions of
a graphics package.
4. Understand geometric transformation.
6. Understand the various concepts and characteristics in geometric
modeling.
7. Understand various data exchange formats.
8. Apply CAD techniques to finite element mesh generation.
9. Understand the basic concepts of CAM
10. Analyze the components and systems of NC and CNC machine
tools.
11. Understand and apply various programming methods for specific
jobs.
12. Understand the concepts of DNC and adaptive control
13. Understand the fundamentals and advantages of group
technology.
14. Classify various CAPP systems.
15. Understand FMS and CIMS with reference to components,
advantages and applications
Course Objectives
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Internal Marks: 40 External Marks: 60 Total Marks: 100
1. Fundamentals of CAD;
Design process with and without computer; CAD/CAM system and its
evaluation criteria, brief treatment of input and output devices,
Display devices; Functions of a graphics package and Graphics
standard GKS, IGES and STEP; Modelling and viewing; Application
areas of CAD.
2. Geometric Transformations:
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surface modeling, concepts of hidden-line removal and shading:
Mechanical Assembly Kinematics analysis and simulation.
4. Representation of curves and surfaces:
Non-parametric and parametric representation of curves. Parametric
representation of Hermite
Cubic, Beizer and B-spline curves; Surface and its analysis.
Representation of Analytical and
synthetic surfaces.
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5. FEM
Overview of FEM, Advantages and applications, recent advance in
FEM, FEA software Basic
Principles and general procedure of FEM.
6. NC/CNC Machine Tools;
NC machine tools- basic components coordinate systems; features of
NC machine tools.
Computerized Numerical Control (CNC): Tooling for NC machines -
tool presetting equipment, flexible tooling, tool length
compensation, tool path graphics; NC motion control system;
Manual part programming, fixed/floating zero. Block format and
codes: Computer assisted part programming. DNC and Adaptive
Control: Direct numerical control: Adaptive control in machining
system; Combined DNC/CNC system.
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Part families; part classification and coding system: Group
technology machine cells:
Advantages of GT.
8. Computer Aided Process Planning:
Introduction and benefits of CAPP. Types of CAPP systems, mach
inability, data selection systems in CAPP.
9. Computer Integrated Manufacturing Systems:
Basic Concepts of CIM: CIM Definition, The meaning of
Manufacturing, Types of
Manufacturing systems; Need, Elements, Evolution of CIM; Benefits
of CIM; Flexible Manufacturing Systems: Physical Components of an
FMS. Types of Flexibility, Layout Considerations; FMS
benefits.
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CAD/CAM
CAD can be defined as the use of computer systems to perform
certain functions in the design process.
CAM is the use of computer systems to plan, manage and control the
operations of manufacturing plant through either direct or indirect
computer interface with the plant’s production resources.
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Geometry Creation
Toolpath Creation
Post Processing
The Product Cycle and CAD/CAM
In order to establish the scope and definition of CAD/CAM in an
engineering environment and identify existing and future related
tools, a study of a typical product cycle is necessary. The
following Figure shows a flowchart of such a cycle.
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Material to be cut
Rough and finish settings
Using the geometry to make a “road map” that the cutting tool will
follow in order to machine the part.
Several parameters must be set:
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- Verification
Most software will let you see a simulation of your part being cut
so you can verify that the toolpath information is correct.
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Translating the toolpath information into a programming language
called G-Code that controls the machine.
From toolpath…
…to G-Code.
CAD/CAM
The machine reads the G-Code and follows the toolpath to cut the
part.
4. Machining the Final Part
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Disadvantages of CAD / CAM
Can be very expensive to set up. A single industrial robot can cost
millions
It can take a long time to train people to use more complex
equipment.
Little need for poorly qualified workers.