Object-oriented Petri nets with changeable structure (OPNs-CS) for production system modeling

We propose object-oriented Petri nets with changeable structure (OPNs-CS) i n this paper for effective modelling of production systems with changing st ructures. Two mechanisms for carrying out the structural changes in OPNs-CS are defined One is for the modification of message passing relationships b etween distinct OPNs and the other is for adding of OPNs to, and the removi ng of OPNs from, a model. A case study is provided to show that OPNs-CS can cope with both the uncertainties which may exist during the model-building phase of a one-of-a-kind production (OKP) system and the structural change s of the system which often occur while the production system is in operati on.