On Petri Net Modeling of Automated Manufacturing Systems

Since the 1980´s, Petri nets (PN) have been widely used to model automated manufacturing systems (AMS) for analysis, performance evaluation, simulation, and control. They are mostly based on process-oriented modeling methods and thus termed as process-oriented PN (POPN) in this paper. The recent study of deadlock avoidance problems in AMS led to another type of PN called resource-oriented PN (ROPN). This paper, for the first time, compares these two modeling methods and resultant models. POPN models the part production processes straightforwardly, while ROPN is more compact. The relations between these two models are investigated. Several AMS examples are used to illustrate them.