A Virtual Assembly System Based on Petri Net Technology

This paper presents a virtual assembly system which supports both assembly and disassembly operation. We give first attempt to construct a systematically interaction framework based on KHOOTPN, short for Knowledge-based Hierarchical Object oriented Timed Petri Net, defined by extending the known Hierarchical Petri Nets (HOONets). As the important module of proposed framework, a Petri net based model is presented and implemented. This model, as a supplement of scenegraph, is used to execute the application information and function corresponding to virtual assembly activities. With the input of dataglove and object behavior information during assembly task, the model output simple events for updating scenegraph to realize the action of virtual assembly. Thus the requestment of real-time and concurrent of VAE is satisfied, the treatment of larger number of discrete events and capture of assembly operation intend is also realized. Finally, the prototype system is established and a case study is presented.