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Computer Aided Manufacturing

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Chapter 2

Neutral Data file

3Prepared by Dr. mohamed Ahmed

Awad

Prepared by Dr. Mohamed Ahmed awad

4

5Winter term 00/01

Neutral File Formats

• DXF - Drawing Exchange Format

• IGES - Initial Graphics Exchange Specification

• CADL- CADKEY Advanced Design Language

• STL - Sterolithography.

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IDA-STEP

An end-user

application

for viewing

and editing

of

STEP data

Lothar Klein, LKSoft

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Definition

IDA-STEP stands for:Integrating Distributed Applications on the Basis of STEP Data Models.

IDA-STEP

• is completely based on JavaTM technology

• runs on top of the STEP toolkit JSDAITM

• is a major result of the IDA-STEP project, partly funded by the European Comission

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IDA-STEPViewer

IDA-STEPViewer

IDA-STEPCenter

IDA-STEPCenter

Architecture

OracleTM / MySQLTM

STEP Database

IDA-STEP DB Bridge

IDA-STEPCenter

STEP-File

IDA-STEPViewer

Feature OverviewPDM viewing and editing• Organization, Person• Product Identification• Classification, - system• Versions, Design View• Properties• Approval, Effectivity• Contract, Security, Certification• Managed Document• Digital File• Assembly Tree• Project, Activity,

Work Request

Geometry

• 3D-Visualization

• 2D-Drawings & Linking

Process Plan andProcess Operation

Data Exchange and Integration

• Import & Export,Workspace concept

• Interactive Merging, Copy & Paste

• STEP Database

• Automatic Merging

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IGES

UG, Ideas, Pro/E - DCI

Floating License on A Network PC

PC-DMIS and CAD system on XP PC with correct DCI enabled on the Portlock

CAD File on Network PC

Or a standalone CAD license (dongle).

IGES

IGES

IGES

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What is an IGES file?

IGES (IGS) stands for Initial Graphics Exchange Specification, an ANSI graphics file format for three-dimensional wire frame models.

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IGES Sections

• The file is divided into 5 Sections, indicated by a character (S, G, D, P, or T) in column 72. The characteristics and geometric information for an entity is split between two sections; one in a two record, fixed-length format (the Directory Entry, or DE Section), the other in a multiple record, comma delimited format (the Parameter Data, or PD Section). Here is a more human-readable representation of the file.

• When displayed, the user should see two yellow points (hard to see on a white background, but most CAD systems use a black background), one located at the origin of model space [0,0,0], two red circular arcs, and two green lines.

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Geometric entities

• Circular Arc (IGES entity #100) • Composite Curve (IGES entity #102) • Conic Arc (IGES entity #104) • Copious Data (IGES Entity #106, forms 1, 2 & 3) • Line (IGES entity #110) • Point (IGES entity #116) • Rational B-Spline Curve (IGES entity #126) • Rational B-Spline Surface (IGES entity #128) • Boundary (IGES entity #141) • Bounded Surface (IGES entity #143) • Curve on a Parametric Surface (IGES entity #142)

20Prepared by Dr. mohamed Ahmed

Awad

21Prepared by Dr. mohamed Ahmed

Awad

22Prepared by Dr. mohamed Ahmed

Awad

23Prepared by Dr. mohamed Ahmed

Awad

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• What is CAM? Nominate then describe briefly the different applications of CAM?

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• Discuss the capabilities of current CAD/CAM systems?

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• Explain the methods of data transfer between dissimilar CAD systems; IGES and PDES?

• Explain the meaning of the different acronym?

• Differentiate among Wire frame, Surface and solid modeling

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Prepared by Dr. mohamed Ahmed Awad

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• (c) Explain the B-rep and CSG methodologies of solid modeling? Then explain their advantages and disadvantages?

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• (d) Show how can you decompose a product model consists of a block having a blind step and a through slot into their lower primitives using both B-rep and CSG?

Prepared by Dr. mohamed Ahmed Awad