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

Abstract

We propose object-oriented Petri nets with changeable structure (OPNs-CS) in this paper for effective modelling of production systems with changing structures. Two mechanisms for carrying out the structural changes in OPNs-CS are defined. One is for the modification of message passing relationships between distinct OPNs and the other is for adding of OPNs to, and the removing 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 changes of the system which often occur while the production system is in operation.