Research On Virtual Environment And Process Management Technology For Virtual Manufacturing

Contemporary Manufacturing System is developing towards network, digitalization, intelligentization and virtualization. VM, as the continuous research focus since it is put forward in the field of CIMS, is regarded as one of the trends of advanced manufacturing in new century. By the research and application on the VM key technologies, enterprises will win market competition with shorter time, higher quality, lower cost and better service, which makes the study on VM has important theoretical and practical significance.The dissertation discusses the research strategies and key technologies of VM on the basis of analysis of the definition, developing background and research status of VM. By using the thought of technology integration, a new VMS architecture based on hierarchical opening network was proposed. It can provide guidance for application integration of VMAim at the characters of process management and related process model of VM, the project-task-active model is proposed and functions of model are described in detail. The multi-view task data model based on structure of relation is presented. With the double-node network planning methods, the collaborative process model is built on the layer of tasks. Based on critical task scheduling, resources and stuffs of project are monitored and adjusted. The engines, triggers and state monitors of tasks are all designed and the dynamic control methods are developed. The theory and method of process management provide guarantee for collaborative work of multidisciplinary teams in VM process.The research content of VM 3D virtual environment is analyzed. The technique of geometry modeling and the method of behavior modeling of entity in the virtual environment are studied. The system architecture of VME is proposed. To provide graph engine supporting VME, a reusable component, which supports 3D modeling and simulation, is established. On the view of object-oriented, the structure of virtual machining device is analyzed. The geometry modeling based on assembly hierarchy relation is proposed and behavior modeling based on kinematics is established. Based on character of different NC code parser, its structure and realized method are built. The vector computing method of collision detection for the process of cutter radius compensation is built up. Aim at the real-time of process simulation, a simulation algorithm of machining process based on discretized triangulation of work-piece is introduced. The prototype system based on these theories provides tools for analyses and evaluation of virtual part machinability.The strategies and method of plant layer description for virtual machining device based on network environment is discussed, in which VRML is one of the important tools. The system framework of multi-user shared virtual plant environment is put forwards. The system design of objectives, server and communication component, the description of multi-user scene and avatar, and running mechanism are described in detail. It can provide analyses for distributed collaborative work.