Web-based virtual reality in manufacturing applications

1. Web-based virtual reality in manufacturing applications Ramanan S. Tiruvannamalai 08/08/2002

2. Agenda • Virtual Reality (VR) • VR Types • Web-based VR-VRML • VRML • Manufacturing applications • Advantages • Limitations • Case study • Conclusions

3. Virtual Reality (VR) • Virtual + Reality • Virtual – “Real in effect although not in fact” • Reality – “can be considered capable of being considered fact for some purposes” • VR is an oxymoron Wilson, J. R. (1997)

4. Virtual reality (VR) Cont.. “Virtual reality is a highly interactive computer-based environment, where the user participates in a ‘virtually real’ world through multiple sensorial channels.” Mikropoulos, T. A. et al. (1998)

5. VR types Broadly categorized into three types • Immersive environment • CAVE system, Head Mounted Display (HMD) • Semi-immersive environment • Large screen projection system with or without stereo • Non-immersive environment • Monitor based viewing of 3D objects

6. Web-based VR VRML – Virtual Reality Modeling Language • Scene description language • Open and platform independent standard • Creates Three Dimensional (3D) interactive interface on the Internet • Scene is composed of list of nodes • Nodes describe things such as shapes, colors, viewpoints, and transformations • 3D analog to HTML • Currently VRML is being replaced by X3D (eXtensible 3D) www.web3d.org

7. VR manufacturing applications Virtual prototyping of a sailing yacht Procedure: • Provide designers with blueprints and lines plan • Create 3D CAD models using AutoCAD • Derive polygonal approximation for the virtual model • Use texture maps for realistic appearance • Develop passive virtual model • Place virtual model on the World Wide Web

8. Virtual prototyping of a sailing yacht Deck layout of virtual sailing yacht Interior view of virtual sailing yacht

9. Advantages – Virtual prototyping • Allows remote customers to inspect the design details • Improves decision making • Improves negotiation and customer approval • Reduces number of iterations • Reduces time and money

10. VR Applications Contd.. Simulation of ship production processes Procedure: • Design double bottom section for a PD 337 navy cargo ship using AutoCAD • Simulate the assembly sequence • Convert into virtual model (VRML) • Post the virtual model on the Internet

11. Simulation of ship production processes Location of section Interior structure with top plate removed

12. Advantages – Ship Prod. processes • Detects design errors in early stage • Communicates errors effectively over the web to other departments • Reduces costly time delays • Analyzes clearances and possible collisions • Supports concurrent engineering

13. Advantages of web-based VR • Improves decision making process • Supports collaborative environment • Improves communication • Supports concurrent engineering • Improves product quality • Supports study of design alternatives • Reduces time and cost

14. Limitations of web-based VR • Requires powerful computer system with improved graphics hardware • Requires more computational power • For complex models (higher polygon count) • Polygon count Vs Rendering speed • Requires high capacity networks • Like Internet2, powerful desktops

15. Case study – Boeing VR project • VRML created in Quest • Identifies the factors affecting VRML file size • Highlights critical factors • Addresses these limitations to reduce file size for faster rendering

16. Case study Cont…

17. Case study – Boeing VR project Basic Quest model With IGRIP workcell

18. Case study – Boeing VR project With catia parts With machine kinematics

19. Conclusions • Web-based VR • Supports collaborative environment • Improves decision making • Improves communication • Suitable for SLVR project (NSF) and Boeing VR project • Polygon count of virtual models should be kept as low as possible for higher rendering speed

20. References • Anonymous, Web3Dconsortium, VRML, [Online], Available:http://www.web3d.org/vrml/vrml.htm [2002, Aug 2]. • Beier, K. P.(2000, March). Web-based virtual reality in design and manufacturing applications. Proceedings of the 1st International Euro Conference on Computer Applications and Information Technology in the Maritime Industries, Potsdam, Germany. • Mikropoulos, T. A., Chalkidis, A., Katsikis, A., & Emvalotis, A. (1998). Students’ attitudes towards educational virtual environments, Education and Information Technologies, 3, 137-148. • Wilson, J. R. (1997). Virtual environments and ergonomics: needs and opportunities, Ergonomics, 40, 10, 1057-1077.