Development of a virtual factory emulator based on three-tier architecture

The virtual factory can provide a total solution for shortening manufacturing cycle time and achieving customer satisfactions. Hence, many world-class companies dedicate themselves to establish their own virtual factories. However, it is difficult to implement a virtual factory because of the lack of assistant tools. A three-tier architecture based colored timed Petri net emulator is developed in the paper to provide such kind of tool. The three-tier architecture based emulator is easy to maintain and extend. This paper adopts UML and Microsoft COM/DCOM techniques to design and implement the emulator, respectively. The emulator is suitable to model complex systems, especially those with concurrent and asynchronous behaviours. In addition, this emulator provides distributed simulation ability. Each emulator can communicate with each other to achieve the concurrence among subnets. In particular, the proposed emulator can be integrated with the WWW and a voice system. Finally, the emulator is used to construct a flexible manufacturing system, and demonstrate its feasibility for virtual factory applications