Petri net based synthesis method to construct optimal controllers and its application to a jobshop scheduling

Abstract

The goal of this paper is to propose a design method of closed-loop Petri net model respecting user specifications. We propose a synthesis method for optimal controllers based on the supervisory control and the Petri nets formalism. By proposed the method, forbidden, enabled and cycle sequences of transitions are found. In addition, the method proposes a general integer programming to determine the incidence matrix and the initial marking of controller with the minimal number of control place. In this work, one assumes that the production system is based on jobshop scheduling with shared resources. A jobshop scheduling example is presented to illustrate the proposed method.