HRM Essay Marketing Essay Accounting Assignment Media Management Finance Essay Law Essay & Assignment Economics EssayComputer Science Engineering Essay Leadership Essay Knowledge Managment Management Essay


A Virtual Environment for Collaborative Assembly
Xiaowu Chen, Nan Xu, Ying Li
The Key Laboratory of Virtual Reality Technology, Ministry of EducationSchool of Computer Science and Engneering, Beihang University
Beijing 100083, P.R. China)
To allow geographical dispersed engineers toperform an assembly task together, a VirtualEnvironment for Collaborative Assembly (VECA) hasbeen developed to build a typical collaborative virtualassembly system. This presents the key 留学生计算机论文定制parts of VECA,such as system architecture, HLA-based (High LevelArchitecture) communication and collaboration,motion guidance based on collision detection andassembly constraints recognition, data translationfrom CAD to virtual environment, reference resolutionin multimodal interaction.
1. Introduction
Virtual reality (VR) is a technology which is oftenregarded as a natural extension to 3D computergraphics with advanced input and output devices. NowVR has matured enough to warrant serious engineeringapplications [1]. As one of the important applicationdomains of VR, virtual assembly (VA) fulfills designflexibility by replacing physical objects with the virtualrepresentation of machinery parts and providing
advanced user interfaces for users to design andgenerate product prototypes [2]. VA can evaluate andanalyze product assembly and disassembly during theproduct design stage with the goal of reducingassembly costs, improving quality and shortening timeto market [3].With the distributed fashion of companies andresearch organizations, many design, assembly,manufacture, analysis works require the collaborationof geographical dispersed engineers. CollaborativeThis paper is supported by A.S.T. Fund (VEADAM ), NationalNatural Science Foundation of China (60503066), National ResearchFund (51404040305HK01015), China Education and Research Grid
(ChinaGrid) Program (CG2003-GA004), National 863 Program(2004AA104280) & (SIMBRIDGE).virtual environment (CVE) is a computer system thatallowsremote users to work together in a sharedvirtual reality space [4]. As an important category ofComputer-Supported Cooperative Work (CSCW) andVR, CVE systems have been applied to militarytraining, telepresence, collaborative design andengineering, distance training, entertainment, andmany other personal applications [5].Because of the advantages of CVE and the actualrequirement of industry, collaborative virtual assembly(CVA) is becoming one of research emphases of VA.
There have been many research efforts to developvirtual assembly systems [6][7][8]. A representativesystem is Virtual Assembly Design Environment(VADE) [9] which allows engineers to evaluate,analyze, and plan the assembly of mechanical systems.VADE simulates inter-part interaction for planar andaxisymmetric parts using constrained motions alongaxes/planes which are obtained from the parametricCAD system. In this system, direct interaction issupported through a CyberGlove.In the field of CVA, several systems have beencreated. For example, National Center forSupercomputing Applications (NCSA) and Germany’sNational Research Center for Information Technology(GMD) developed a collaborative virtual prototypingsystem over ATM network [10]. The system integratedreal-time video and audio transmissions let engineerssee other participants in a shared virtual environment ateach remote site’s viewpoint position and orientation.Jianzhong Mo et al. developed a virtual-reality-basedsoftware tool- Motive3D [11] that supportscollaborative assembly/disassembly over Internet andpresented systematic methodology for disassemblyrelation modeling, path/sequence automatic generationand evaluation independent of any commercial CADsystems. Shyamsundar et al. developed an internetbased

UK Thesis Base Contacts