www.sixdindia.com

SIX D INDIA

Design Team Mr. Sangiba Longchar: Head Design (Reverse Engineering) Mr. Joginder Saini: Sr. Design Engineer (Rendering and Texturing) Mr. Yogendra Kumar: Sr. Design Engineer (CAD Modeling Expert)

Project Members Mr. Pawan Panchpal : Project Director(Technical) Mr. Akash Rana : Project Manager (Business) Mr. Rajnish Ojha : Manager (Technical Services)

www.sixdindia.com

Terminology (Abstract ) 3D Scanning and Laser Scanning

3D CAD Modeling (Reverse Engineering)

www.sixdindia.com

3D Scanning - Abstract

3D Scanning and data capture encompasses a number of similar technologies, all of which can be considered optical 3D measurement techniques (or 3D imaging systems), which describes an optical instrument that captures physical data from the environment, either by speed/coherence of light or triangulation (not addressed in this document). Data captured by 3D scanners are usually referenced with known Cartesian (XYZ) coordinate systems, such as Global Navigation Satellite Systems (GNSS), Ordnance Survey (OS), or local project coordinates. A number of industry terms are used to differentiate the ways that data can be captured, processed and delivered.

3D Laser Scanning is a broadly applicable technology for a number of industries adopted in the architecture, engineering, and construction (AEC).3D Laser scanning-terrestrial, mobile or aerial 3D range imaging device that uses a laser (light) to measure distance via time-of-flight, phase-based, or light-based detection. Common terms used in the AEC industry include:

1. LIDAR (Light detection and ranging)- a term commonly used for aerial scanners

2. LADAR (Laser detection and ranging)- commonly used for terrestrial scanners

3. Flash LADAR/LIDAR- emission and detection of light using light arrays and an electro-optical device

www.sixdindia.com

3D CAD Modeling (Reverse Engineering) - Abstract

Reverse Engineering is the practice of analyzing an object or system with the intent of replicating it or understanding how it functions. Reverse engineer can be Applied in the architecture, engineering, and construction (AEC), Organic compound, software program, or a process. Reverse engineering is the opposite of forward engineering. It takes an existing object or system and creates a CAD Model. Reverse engineering is usually undertaken in order to redesign the system for better maintainability or to produce a copy of a system without access to the design from which it was originally produced.

Reverse Design finds wide Applications in:

Duplicating a Physical Product for which no Technical Drawings or CAD data exists

Developing a new product with enhanced functions based on an existing product

Designing a Product from a Mock-up Model or Clay Model in the Automotive Industry, where Aesthetic Design factors are critical

Reconstructing, Preserving and Analyzing Cultural and Historical Assets

Mass Customization of Products associated with the Living bodies (Human , Animals and Organic)

Using Digitized Information for Animation

Manufacturing a products in the Medical and Dental fields

Analyzing The Design Intent from Competitors' Products

www.sixdindia.com

Reverse Modeling Process is the process of creating an optimal 3D model from 3D scan data (Point Cloud or Mesh), that is generated during the Scan Data Processing phase. This process is the core of Reverse Design, where optimized mesh and 3D features, such as 3D curves, 3D surfaces, and 3D solid bodies, are created by using various modeling methods. The Mesh Modeling method creates an optimized mesh that contains important information by applying various geometric and mathematical operations. The Feature Modeling method creates 3D geometric feature shapes based on extracted design intent and elements from 3D scan data The Fitting Surface Modeling method creates fitted freeform surfaces on complex freeform feature shapes. The Hybrid Modeling method creates a complex feature model from 3D scan data by using the Feature Modeling method in conjunction with the Fitting Surface Modeling method.

www.sixdindia.com

The Design Process - Abstract

1. Patch PTS (PointCloud) to Patch STL (SteroLithography)Data Processing:

2. Patch STL to Final Merged STL Data Processing:

3. Merged STL Data to CAD Model Processing:

Structure Based CAD Modeling

Feature Based CAD Modeling

4. Final Assembly of CAD Models

Important Pre Requisite Before The Design Process:

Positioning and Aligning of the Taj Mahal wrt The Mosque(West), The Guest House(East) and The Great Gate (South).

Positioning and Aligning wrt The Geographical Co-ordinates.

www.sixdindia.com

Post registration Data of 3D Laser Scanning in pts (PointCloud) file extension

is Processed and converted into STL (SteroLithography) file extension.

Processing is done in patch by patch as shown in picture below. Resulting in a Single

STL Patch.

This is an automatic Algorithmic Process which results in Useable and Editable STL file extension.

Patch STL No 1 Patch STL No 2 Patch STL No 3

Patch STL No 4

Patch PTS (PointCloud) to Patch STL (SteroLithography) Processing:

Patch STL (SteroLithography) after Processing:

www.sixdindia.com

All Useable and Editable STL Patches (Picture on

Left side are Merged into a Single Water Tight

STL Data (Picture on the Right Picture ).

This Process Executes

Hole Filling.

Noise Removal.

Feature Editing.

Polygonal Mesh Repair.

Decimates no of triangles .

Data Merging

Final Output Data is Exported in STL File

format for Further Processing in CAD

Environment.

Final Merged STL (Front View)

Final Merged STL (Isometric View)

Patch STL to Final Merged STL Data Processing

STL Patches To Merged STL

STL Patches To Merged STL

www.sixdindia.com

Structure Based CAD Modeling

Feature Based CAD Modeling

Structure Based CAD Modeling

Major and Minor Structures are identified.

Final Merged STL is Imported into CAD Environment for Design Intent.

Sections of the STL Data are generated and Transferred to Sketch Mode.

2D Sketch are generated and Transferred into CAD Mode.

Using Appropriate Tools and Commands 3D CAD is developed as per the STL Data.

Merged STL Data to CAD Model Processing:

www.sixdindia.com

STL Cross Section 2D Sketch Drawings 3D CAD Model

STL Cross Section 2D Sketch Drawings 3D CAD Model

Structure Based CAD Modeling of Minarets:

Structure Based CAD Modeling of Main Dome:

STL Section

To

2D Sketch

2D Sketch

To

3D CAD

STL Section

To

2D Sketch

2D Sketch

To

3D CAD

www.sixdindia.com

Feature Based CAD Modeling

Major and Minor Features are identified.

Final Merged STL is Imported into CAD Environment for Design Intent.

Sections of the STL Data are generated and Transferred to Sketch Mode.

2D Sketch are generated and Transferred into CAD Mode.

Using Appropriate Tools and Commands 3D CAD is developed as per the STL Data.

Merged STL Data to CAD Model Processing:

Feature Based CAD Modeling of Wall Carvings:

STL Cross Section 2D Sketch Drawings 3D CAD Model

2D Sketch

To

3D CAD

STL Section

To

2D Sketch

www.sixdindia.com

Final Assembly of CAD Models

Assembly of Structured based 3D CAD

and Featured based 3D CAD are Merged

together to Develop The Final 3D CAD

Model.

Structured based 3D CAD Merged to Final CAD

Featured based 3D CAD to Final CAD

Final 3D CAD Model (Front View) Final 3D CAD Model (Isometric View)

www.sixdindia.com

THANK YOU

www.sixdindia.com