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Semester Dis08 ~ April 09

KJM 573 KJM 573

CAD CAM CAECAD CAM CAE

Introduction to CAD CAE CAM Introduction to CAD CAE CAM

A design drawing for an engine.

What is Computer-aided design (CAD)

The use of computer technology to aid in the

design of a product. Current packages range

from 2D vector base drafting systems to 3D

solid and surface modelers.

Vector graphics (also called geometric modeling or object-

oriented graphics) is the use of geometrical primitives such

as points, lines, curves, and polygons, etc..

Origins and terminology

CAD originally meant Computer-Aided Drafting because of its original use as a replacement for traditional drafting.

Now, CAD usually means Computer Aided Design to reflect the fact that modern CAD tools do more than just drafting.

CAD is sometimes translated as "computer-assisted"

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Computer-aided design (CAD)

CAD is used to design, develop and optimize products, which can be fulfill consumers requirement

CAD is extensively used in the design of tools and machinery, and even in the drafting and design of all types of buildings.

CAD is mainly used for detailed engineering of 3D models and/or 2D drawings of physical components,

CAD also used throughout the engineering process from conceptual design and layout of products, through strength and dynamic analysis of assemblies to definition of manufacturing methods of components.

The CAD process. .

Computer-aided design (CAD)

CAD benefits such as lower product development costs and a greatly shortened design cycle.

CAD enables designers to lay out and develop work on screen, print it out and save it for future editing, saving time on their drawings.

Commercial Floor Plan

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Fully editable digital multi-CAD mockup

Fields of use

The Architecture, Engineering, and Construction (AEC) Industry

Architecture

Architectural engineering

Interior Design

Interior Architecture

Building engineering

Civil Engineering and Infrastructure

Construction

Roads and Highways

Railroads and Tunnels

Water Supply and Hydraulic Engineering

Storm Drain, Wastewater and Sewer systems

Mapping and Surveying

(Chemical) Plant Design

Factory Layout

Heating, Ventilation and air-conditioning (HVAC)

Mechanical (MCAD) Engineering

Automotive - vehicles

Aerospace

Consumer Goods

Machinery

Shipbuilding

Bio-mechanical systems

Electronic design automation (EDA)

Electronic and Electrical (ECAD)

Digital circuit design

Electrical Engineering

Power Engineering or Power Systems Engineering

Power Systems CAD

Power analytics

Manufacturing process planning

Industrial Design

Software applications

Apparel and Textile CAD

Fashion Design

Garden design

Lighting Design

Sketchpad

History

A turning point was the development of SKETCHPADsystem in MIT in 1963 by Ivan Sutherland

The distinctive feature of SKETCHPAD was that it allowed the designer to interact with his computer graphically: the design can be fed into the computer by drawing on a CRT monitor with a light pen. Effectively, it was a prototype of graphical user interface, an indispensable feature of modern CAD.

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History

• First commercial applications of CAD -large companies (automotive, aerospace, electronics industries)

1. 1964 GM with DAC-1 (Design Augmented by Computer); ; Bell GRAPHIC 1

2. 1971 Renault (Bezier) – UNISURF car body design and tooling.

• 1971 Dr. P. J. Hanratty, wrote ADAM (Automated Drafting And Machining) code and supplied to companies McDonnell Douglas (Unigraphics), Computervision (CADDS)

• 1960s and 1970s foundation of CAD systems United Computing, Intergraph, IBM, Intergraph IGDS in 1974 (which led to Bentley MicroStation in 1984)

• CAD implementations have evolved dramatically since then.

• 2D in the 1970s, it was typically limited to producing drawings similar to hand-drafted drawings.

• Solid modeling in the 1980s, have allowed more versatile applications of computers in design activities.

History

• 1981 Key products of solid modelling packages launched -Romulus(ShapeData) and Uni-Solid (Unigraphics) based on PADL-2 and the release of the surface modeler CATIA (Dassault Systemes).

• Autodesk was founded 1982 by John Walker, which led to the 2D system AutoCAD.

• The next milestone was the release of Pro/ENGINEER in 1988, which heralded greater usage of feature-based modeling methods and parametric linking of the parameters of features.

• End 80s~early 90s. Ian Braid development the B-rep solid modeling kernels (engines for manipulating geometrically and topologically consistent 3D objects) Parasolid (ShapeData) and ACIS (Spatial Technology Inc.)

• Release of mid-range packages; SolidWorks in 1995, SolidEdge (Intergraph) in 1996, IronCAD in 1998.

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Major Software Provider

Company NameAnnual recenue (US&)

Product Name Product Type Origin

Autodesk $1,840M

AutoCAD and Architectural Desktop

CAD

California USAMechanical Desktop CAD

Autodesk Inventor CAD

Dassault System $1,100MCATIA CAD/CAM/CAE

FranceSolidworks CAD

Parametric Technology Corporation

$700M Pro/ENGINEER CAD USA

Siemens PLM Solutions (Formerly UGS Corp. Unigraphics Solutions)

$1,100MNX CAD/CAID/CAM/CAE USA -UGS

Siemens-GermanSolid Edge CAD

CAD Capabilities

1. Wireframe geometry creation

• A wire frame model is a visual presentation of an electronic representation of a three dimensional or physical object used in 3D computer graphics

• The wire frame format is also well suited and widely used in programming tool paths for DNC (Direct Numerical Control) machine tools.

wireframe cube, icosahedron, and approximate sphere

A wireframe image using hidden line removal

A surface shaded object (not wireframe)

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CAD Capabilities

2. 3D parametric feature based modelling, Solid modelling (link)

3. Freeform surface modeling

4. Automated design of assemblies, which are collections of parts and/or other assemblies

CAD Capabilities

5. Create Engineering drawings from the solid models

Isometric projection of the object

Sectional views are indicated by the

direction of arrows

Multiple views and projections

1st Angle and 3rd angle projection

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An example of a CAD engineering drawing.

CAD Capabilities

6. Import/Export routines to exchange data with other software packages

There are basically three methods of transferring data from one CAD system to another.• Direct CAD system export/import • Direct 3rd party translators. • Intermediate data exchange formats

1. IGES

2. STEP

3. VDA-FS

4. DXF

5. Parasolid

6. JT

7. DRG

CAD Capabilities

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7. Output directly to a Rapid Prototyping or Rapid Manufacture Machine for

industrial prototypes

8. Reuse of design components

9. Ease of modification of design of model and the production of multiple

versions

10. Automatic generation of standard components of the design

11. Validation/verification of designs against specifications and design rules

12. Simulation of designs without building a physical prototype

13. Output of engineering documentation, such as manufacturing drawings,

and Bills of Materials to reflect the BOM required to build the product

14. Output of design data directly to manufacturing facilities

15. maintain libraries of parts and assemblies

16. calculate mass properties of parts and assemblies

17. aid visualization with shading, rotating, hidden line removal, etc...

CAD Capabilities

The Effects of CAD

Starting in the late 1980s, the development of readily affordable CAD programs that could be run on personal computers

One CAD operator could readily replace at least three or five drafters using traditional methods.

Engineers began to do their own drafting work, further eliminating the need for traditional drafting departments.

This trend mirrored that of the elimination of many office jobs traditionally performed by a secretary as word processors, spreadsheets, databases, etc. became standard software packages that "everyone" was expected to learn.

.

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Today, hardware and software costs have come down. Even high-end packages work on less expensive platforms and some even support multiple platforms.

The adoption of CAD in engineering schools was not without resistance, however. • sketching on a computer screen did not replicate the skills associated

with practice of sketching in a sketchbook.• students would be hired for their computer skills rather than their

design skill, as was indeed common in the 1990s.

Today, education in CAD is now accepted across the world in schools of engineering.

The Effects of CAD

� CAD - Computer Aided Design

� CADD - Computer Aided Design and Drafting

� CAE - Computer Aided Engineering

� CAM - Computer Aided Manufacturing

� CAPP - Computer Aided Process Planning

� CATD - Computer Aided Tool Design

� CAP - Computer Aided Planning

COMPUTER AIDED PROCESSCOMPUTER AIDED PROCESS

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COMPUTER AIDED ENVIRONMENTCOMPUTER AIDED ENVIRONMENT

Product Cycle in computerized manufacturing Product Cycle in computerized manufacturing environmentenvironment

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COMPUTER AIDED DESIGN (CAD)COMPUTER AIDED DESIGN (CAD)

� A technology which incorporates computer based tools to create and store product design information.

� Design is an activity which needs to be organized and consider all aspect in product development.

� Complexity of design process increases with number and diversity of components present in final part.

� Example of software: AutoCAD, CATIA,Solidworks

Stages in Design ProcessStages in Design Process

Design Phase Required CAD tools

Conceptualization Geometric modeling techniqueGraphic aidsManipulationVisualization and RPT

Modelling and simulation All aboveAnimationAssemblies

Analysis Analysis packagesCustomized programs and packages

Optimization Customized applicationsStructural optimzation (eg FEA)

Evalution DimensioningTolerancesBill of materialsRPT and CNC

Communication and documentation

Drafting and detailing

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CAD advantagesCAD advantages

COMPUTER AIDED MANUFACTURING (CAM)COMPUTER AIDED MANUFACTURING (CAM)

� Technology which translates product design into information required for overall process planning of its production-the manufacturing process.

� This involves factory management and control with aid of computerized systems and may include numerical machine tools and robotics

� Example of software: Mastercam, SPC software

� Types of production: Mass production, Batch production, Job shop production

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CAM in Manufacturing Activity

Industrial manufacturing can be categorized into:

Mass Production

• Very high volume justifying the used of special purpose machine

and transfer lines

• Very flexible

Batch Production

• Making of job in medium lots

• Transfer lines may not be used but special purpose machines

which can be easily modified through jigs and fixtures can be used

Job shop production

• Manufacture of very small lots, often of single jobs

• No special purpose machines or tooling are economically justified

• Normally uses general purposed machines and tooling and can be

a lengthy and error prone process

Types of Computer Controlled Machines

• CAM can be applied in all three

types of manufacturing activities

• Application is more important in

batch and job shop production

due to the amount of data and

flexibility required.

• Numerical control (NC) can

provide flexibility in

manufacturing.

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Manufacturing phases Manufacturing phases

Manufacturing Phase Required CAM tools

Process planning CAPP techniquesCost analysisMaterial and tooling specification

Part programming CNC, Robot and CMMProgramming

Analysis Analysis packagesCustomized programs and packages

Inspection Inspection software

Assembly Robotic simulation and programming

CAM advantagesCAM advantages

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COMPUTER AIDED ENGINEERING (CAE)COMPUTER AIDED ENGINEERING (CAE)

� Category of software that helps in the design, assessment, and manufacture of engineering products.

� CAE covers a wide spectrum of engineering disciplines such as: structural,thermal,fluid flow(eg gases and liquids), Electromagnetics, Optimzation.

� Example of software: ABAQUS,ANSYS etc.

� In general, there are three phases in any computer-aided engineering task:

• Pre-processing – defining the model and environmental factors to be applied to it. (typically a finite element model)

• Analysis solver (usually performed on high powered computers)

• Post-processing of results (using visualization tools)

Example:Example:

FEA of random vibration in a beam. Colors

or gray scales are often used to show

degrees

of stress and deflection (Courtesy of

Algor, Inc.)