A Realistic Virtual Assembly Training System Supporting Multi-person Collaborative Work

In recent years,virtual reality technology has developed rapidly and is widely used in military,education,medical,manufacturing,entertainment and so on.It has brought about great changes to our lives.As an important application of VR technology in intelligent manufacturing filed,virtual assembly technology has various advantages in many aspects.For example,in industrial production filed,the assembly training in the real environment has many restrictions,while virtual assembly system can create a virtual scene close to the real environment for the users,which helps users to realize the simulation of model assembly.In addition,the virtual assembly system can be used repeatedly and supports multiple users to cooperate,greatly improving training efficiency.Virtual assembly technology breaks the limitations of time,space and hardware conditions in the traditional assembly environment with its economy,safety,flexibility and high efficiency,which greatly facilitates the use of users.At the same time,because some assembly processes require multiple-users'collaboration,supporting multi-person interaction is necessary for the virtual assembly system.So how to provide a collaborative virtual environment for assembly systems has become one of the research priorities among scholarsAt present,there are many researches about virtual assembly system,but most of them still have limitations.For example,some systems use head-mounted VR display devices.Although it can enhance the user's sense of immersion,users cannot communicate well because of the complete isolation from real environment.Projection or desktop display systems cannot meet the needs of multi-screen simultaneous display in terms of multi-user collaboration,and user's sense of immersion declines.This paper developed a realistic virtual assembly training system supporting nulti-person collaborative work,which improves the above problems existing in the existing system and achieves the goal of assembly training simulation.According to the actual requirement of multi-user collaboration in the assembly process,this paper carried out demand analysis and overall system design.The system is based on VR projection stereoscopic displaying technology,and use Unity 3D engine and Visual Studio as the development platform.We also use Maya tool as a model tool,and MySQL database to store and modify users' data.This system is developed with a variety of technologies,including multi-vie'w stereoscopic display technology,view-dependent rendering technology,Kinect location and gesture recognition technology,which can provide users with richer and more authentic experience effects.This paper describes the system design and implementation process in detail.It fully considers the interactive experience of multi-user collaboration,and mainly achieves the following design:Firstly,it designs the tree diagram display of assembly model.Secondly,multi-view stereoscopic display based on view-dependent rendering is realized.Finally,it provides multi-user collaborative interaction.In addition,this system also provides users with users'information management and assembly process observe module.In general,this system has implemented the multi-user co-located collaboration and multi-view rendering.It strives to effectively save activity space for users in the mode of multi-user collaborative work,and at the same time,solves the problems of network communication delay with multi-user involvement,which has positive significance for co-located collaboration research.