Failure modeling and process monitoring for flexible manufacturing systems using colored timed Petri nets

The performance of a flexible manufacturing system (FMS) depends on the equipment efficiency and process control. In order to increase the equipment efficiency, the failure mode analysis and fault diagnosis can be used to reduce the frequency of unexpected breakdowns of machines. In addition, the statistical process control (SPC) can be used for adjusting the process parameters to eliminate process variations. In this paper, a colored timed Petri net (CTPN) is used to model the process behavior of an FMS. In addition, the CTPN-based SPC, fault diagnosis, and failure model and effect analysis are modeled and analyzed individually. Especially, all of the modular models are integrated and linked based on the CTPN. Due to the unified CTPN modeling, the information of each modular model in the entire system can be exchanged and integrated directly and efficiently. Finally, the entire CTPN FMS models are implemented using G2 real-time expert system. Consequently, the proposed CTPN-based simulator can be acted as a real-time FMS monitor and controller through the G2 standard interface.