Product Data Interfaces in CAD/CAM Applications

1 Introduction - Reference Models, Interfaces, Integration Issues.- 1.1 Goals in the Application of CAD Interfaces.- 1.1.1 Global Objectives.- 1.1.1.1 Introduction.- 1.1.1.2 Ranges of Application for the CAD Interfaces.- 1.1.1.3 Global Objectives for the Application of Computer Assisted Systems and of CAD Interfaces.- 1.1.2 Application of CAD Interfaces in Computer Assisted Processes.- 1.1.2.1 Product Concept.- 1.1.2.2 Construction, Calculation, Testing.- 1.1.2.3 Manufacturing Engineering.- 1.1.2.4 Assessment in Relation to Objectives.- 1.1.3 Current and Future Developments in CAD Interfaces from the Application Standpoint.- 1.1.4 References.- 1.2 Interfaces and Data Transfer Formats in Computer Graphics Systems.- 1.2.1 Introduction.- 1.2.2 Data Interfaces.- 1.2.3 The Standards for Graphics Programming (GKS,D-GKS, GKS Output Level 3, GSPC Core and PHIGS) 16.- 1.2.4 Graphics Metafiles (GKSM and VDM).- 1.2.5 Device and Workstation Interfaces (VDI and WSI).- 1.2.6 Videotex Files (NAPLPS and CEPT/VPLP).- 1.2.7 Product Data Transfer Formats (IGES, VDAFS, TAP, EDIF).- 1.2.8 Graphics in the Processing of Text Documents Which Include Graphics (CLPT).- 1.2.9 Presentation Graphics Layer on Top of GKS.- 1.2.10 GKS in a Network Environment.- 1.2.11 References.- 1.3 CAD/CAM: Integration in the Automobile Industry.- 1.3.1 Introduction.- 1.3.2 Demands on and Requirements of an Integrated Concept.- 1.3.3 The CAD/CAM Process Chain in Automobile Manufacturing.- 1.3.3.1 Product Model and Data Management.- 1.3.3.2 Information and Communication in the Process Chain.- 1.3.4 System Engineering Aspects of an Integrated CAD/CAM Concept.- 1.3.4.1 A Possible Hardware Architecture.- 1.3.4.2 Network Architecture.- 1.3.4.3 Software Architecture.- 1.4 Interfaces for CAD Applications.- 1.4.1 Introduction.- 1.4.2 CAD Systems.- 1.4.3 Interface Possibilities.- 1.4.4 Communication.- 1.4.5 Interface Requirements.- 1.4.6 Interface Standards.- 1.4.7 Data Base Interface.- 1.4.8 Interface Implementations.- 1.4.9 Conclusion.- 2 Graphics Systems - Graphical Standards - GKS.- 2.1 Graphical Standards.- 2.1.1 Introduction.- 2.1.2 The Graphical Kernel System - GKS.- 2.1.3 GKS and Other Graphics Standards.- 2.1.4 Language Bindings.- 2.1.5D-GKS 77.- 2.1.6 PHIGS.- 2.1.7 Metafiles and Device Interfaces.- 2.1.8 Certification, Formal Specification, Registration.- 2.1.9 Graphics and CAD.- 2.1.10 Graphics in Documents.- 2.1.11 Outlook.- 2.1.12 References.- 2.2 GKS and Intelligent Terminals.- 2.2.1 Introduction.- 2.2.2 Intelligence of Terminals.- 2.2.3 GKS Driver Interfaces.- 2.2.4 Utilization of Local Intelligence by GKS.- 2.2.5 Problems: GKS versus Intelligent Terminals.- 2.2.6 Minimal GKS.- 2.2.7 Distribution of GKS in Kernel, Driver, Device and Utilities.- 2.2.8 References.- 2.3 Tektronix PLOT 10 GKS - Tailored for Customer's Needs.- 2.3.1 Introduction.- 2.3.2 Dynamic Memory Management.- 2.3.3 A New View of Workstations.- 2.3.4 A Standards Solution to Graphics Problems.- 2.3.5 Standardization Means Device Independence.- 2.4 Common Graphics Manager - Design Concepts.- 2.4.1 Introduction.- 2.4.2 Concepts of GKS.- 2.4.3 Further Standards.- 2.4.4 Design Concepts.- 2.4.5 Design Realization.- 2.4.6 Conclusions.- 2.4.7 Appendix.- 2.4.8 References.- 2.5 GKSGRAL - Software and Hardware Realizations of the Graphical Kernel System.- 2.5.1 Introduction.- 2.5.2 The GKSGRAL System Structure.- 2.5.2.1 The GKSGRAL Kernel.- 2.5.2.2 The GKSGRAL Workstation Interface.- 2.5.2.3 The GKSGRAL Workstation Layer.- 2.5.2.4 The GKSGRAL Device Interface.- 2.5.2.5 The GKSGRAL Device Driver Layer.- 2.5.3 GKSGRAL Interfaces'.- 2.5.3.1 Language Interfaces.- 2.5.3.2 Metafile Interfaces.- 2.5.3.3 Graphical Device Interfaces.- 2.5.3.4 Symbol Interfaces.- 2.5.4 The GKSGRAL Workstation Handler.- 2.5.5 The GKSGRAL Metafile Handler.- 2.5.6 The GKSGRAL Segment Storage Handler.- 2.5.6.1 Purpose.- 2.5.6.2 The Storage Module Interface.- 2.5.6.3 Storage Module Structure.- 2.5.6.4 Integration of the WISS into GKSGRAL.- 2.5.7 GKSGRAL Input.- 2.5.8 GKSGRAL Configuration Possibilities.- 2.5.9 GKSGRAL Installations.- 2.5.10 GKSGRAL Device Drivers.- 2.5.11 The GKSGRAL Engine.- 2.5.11.1 Functionality.- 2.5.11.2 Advantages.- 2.5.11.3 Software/Firmware.- 2.5.11.4 Hardware.- 2.5.11.5 Extensions.- 2.5.12 References.- 3 Initial Graphics Exchange Specifications - Implementation, Experience.- 3.1 Product Data Exchange; Design and Implementation of IGES Processors.- 3.1.1 Abstract.- 3.1.2 Introduction.- 3.1.3 IGES: Overview.- 3.1.4 IGES: Intrinsic Problems.- 3.1.4.1 IGES Entity Set.- 3.1.4.2 IGES Format.- 3.1.4.3 IGES Translators.- 3.1.5 Design of an IGES Translator.- 3.1.5.1 Internal IGES Files (IIF).- 3.1.5.2 IIF Interface.- 3.1.5.3 Functions of the EDIT Phase.- 3.1.5.4 Functions of the EXCHANGE Phase.- 3.1.6 Summary.- 3.1.7 References.- 3.2 Experience Gained Using the IGES Interface for CAD/CAM Data Transfer.- 3.2.1 Introduction.- 3.2.1.1 CAE Use in Product Development.- 3.2.2 Areas of Applications of the IGES Interface at BMW.- 3.2.2.1 Data Exchange Between CAD Systems.- 3.2.2.2 Data Exchange Between CAD and CAM Systems.- 3.2.2.3 Data Exchange Between CAD and Calculation Systems.- 3.2.3 Basic Problems in the Field of CAD Data Transfer.- 3.2.3.1 CAD System Variety.- 3.2.3.2 IGES Interface Definitions.- 3.2.3.3 IGES Processors.- 3.2.3.4 Transfer Media.- 3.2.4 Example of Practical Use.- 3.2.5 Verification of IGES Processors from the User's Point of View.- 3.2.6 Summary.- 3.2.7 References.- 4 VDAFS - Functionalities, Approximation Methods, Implementation, Experience.- 4.1 VDAFS - A Pragmatic Interface for the Exchange of Sculptured Surface Data.- 4.1.1 History.- 4.1.2 Pragmatic Goals.- 4.1.2.1 Geometrical Elements.- 4.1.2.2 General Properties.- 4.1.2.3 Remarks.- 4.1.3 Example.- 4.1.4 Syntax and Rules.- 4.1.4.1 General Rules.- 4.1.4.2 Geometrical Elements.- 4.1.4.3 Non-Geometrical Elements.- 4.1.5 Really Pragmatic?.- 4.1.5.1 Why Not IGES?.- 4.1.5.2 VDAFS-State of the Art.- 4.1.6 Further Developments.- 4.1.7 References.- 4.2 Approximation Methods Used in the Exchange of Geometric Information via the VDA/VDMA Surface Interface 150.- 4.2.1 Introduction.- 4.2.2 The VDA-VDMA Surface Interface.- 4.2.3 Approximation Methods.- 4.2.3.1 Goals.- 4.2.3.2 Degree Reduction.- 4.2.3.3 Degree Elevation.- 4.2.3.4 Results.- 4.2.4 Conclusions.- 4.2.5 References.- 4.3 A Tentative Implementation of VDAFS.- 4.3.1 A Short Description of VDAFS.- 4.3.2 Implementation.- 4.3.3 Usage.- 4.3.4 Problems.- 4.3.5 References.- 4.4 Implementation of a VDA Interface in the CAD System STRIM 100.- 4.4.1 Abstract.- 4.4.2 Introduction.- 4.4.3 STRIM: the Product 167.- 4.4.4 Basic Concepts of the Interface.- 4.4.5 VDA Output.- 4.4.6 VDA Input.- 4.4.6.1 Check.- 4.4.6.2 Contents.- 4.4.6.3 Transfer.- 4.4.7 Preliminary Experience.- 4.4.8 Conclusion.- 4.4.9 References.- 4.5 The Implementation of the VDAFS Geometric Data Interface on Computervision's CDS 4000 CAD/CAM System.- 4.5.1 Introduction.- 4.5.2 "What is the VDAFS Interface?".- 4.5.2.1 Geometric Data Interfaces.- 4.5.2.2 General Description of VDAFS.- 4.5.2.3 Objectives of VDAFS.- 4.5.2.4 Comparison with Other Geometric Data Interfaces.- 4.5.3 Implementation of the VDAFS Interface on the CDS 4000.- 4.5.3.1 PUT VDAFS-Creation of the VDAFS File.- 4.5.3.2 GET VDAFS - Creation of the CADDS 4X Part from the VDAFS File.- 4.5.3.3 Correspondence between CADDS 4 X Entities and VDAFS Records.- 4.5.3.4 Implementation Philosophy.- 4.5.4 Future Developments.- 4.6 Experience with VDAFS.- 4.6.1 Introduction.- 4.6.2 VDA-Working Group "Test".- 4.6.3 VDA-Interface Test.- 4.6.4 VDAFS-Interface Problems Resulting from CAD/CAM Systems.- 4.6.5 VDAFS - Disadvantages.- 4.6.6 VDAFS - Extensions.- 4.6.7 Outlook.- 4.6.8 References.- 5 Specification and Validation.- 5.1 Specification of Interfaces: A Case Study of Data Exchange Languages.- 5.1.1 Introduction.- 5.1.2 The First Part of the Case Study.- 5.1.3 The Types of CADE.- 5.1.4 The Types of CADA.- 5.1.5 The Semantics of the Data Transfer.- 5.1.6 The Second Part of the Case Study.- 5.1.7 A Concrete Interface Language.- 5.1.8 A Glance at the Development of Programs.- 5.1.9 References.- 5.1.10 Appendix: Pascal Implementations.- 5.2 Validation of Graphics Systems.- 5.2.1 Introduction.- 5.2.2 Goals of Certification.- 5.2.3 Software Validation Techniques.- 5.2.4 The Interfaces for Testing.- 5.2.4.1 Testing at the Application Interface.- 5.2.4.2 Testing at the Operator Interface.- 5.2.4.3 Testing at the Device Interface.- 5.2.4.4 Configuring a Reference System.- 5.2.5 Conclusions and Further Planning.- 5.2.6 References.- 5.3 Testing and Validation of IGES Processors.- 5.3.1 Introduction.- 5.3.2 Basic IGES Concepts.- 5.3.3 General Test Criteria.- 5.3.3.1 Entity Set.- 5.3.3.2 Exchangeability.- 5.3.3.3 Functionality.- 5.3.3.4 Graphical Representation.- 5.3.3.5 Accuracy.- 5.3.3.6 Syntactical Correctness.- 5.3.3.7 Software Quality.- 5.3.4 Test of IGES Processors.- 5.3.4.1 Test Methods.- 5.3.4.2 IGES Test Library.- 5.3.4.3 Test Data.- 5.3.5 Validation of Test Results.- 5.3.5.1 Comparing Pictures.- 5.3.5.2 Comparing Data Bases.- 5.3.5.3 Comparing Operations.- 5.3.5.4 Handchecking.- 5.3.5.5 Software Tools.- 5.3.6 IGES File Analysis System.- 5.3.7 Test Concept and Future Outlook.- 5.3.8 References.- 6 Outlook.- 6.1 Progress in the Development of CAD/CAM Interfaces for Transfer of Product Definition Data.- 6.1.1 Transfer of Product Definition Data.- 6.1.1.1 The Necessity for Transfer of Product Definition Data.- 6.1.1.2 Product Definition Data as an Internal Computer Model.- 6.1.1.3 Principle of Operation and Status of Implementation of CAD/CAM Interfaces.- 6.1.2 CAD/CAM Interface Development.- 6.1.2.1 Requirements of a CAD/CAM Interface from the Application Viewpoint.- 6.1.2.2 General Requirements for a CAD/CAM Interface Concept.- 6.1.3 Status of Standardization of an Interface for Transfer of Product Definition Data in Germany.- 6.1.4 References.- Contributors.