On the hierarchical modeling analysis and simulation of flexible manufacturing systems with extended Petri nets

A class of Petri nets, called extended Petri nets, with multiple types of places, multiple classes of tokens and multiple arcs is proposed. It is utilized for the hierarchical modeling of flexible manufacturing systems, ensuring a priori that the extended Petri net system model obtained is live, bounded, consistent and error free. The proposed method views the operation of the flexible manufacturing system as a process that is decomposed into operations with specified precedence relations. For each operation the required resources are identified, and on the basis of these requirements the overall system is decomposed into a set of finite subsystems. The operation of each subsystem is modeled as an event graph representing a single resource activity cycle. The extended Petri net system model is synthesized from these component nets using certain synthesis rules. A software package has been developed to simulate the execution of the model obtained