Uma nova abordagem para a síntese de supervisores de sistemas a eventos discretos.

Abstract

Petri nets have been widely used to specifying, designing, analyzing and controlling discrete event systems. In the same way, the supervisory control theory, together with Petri nets, has been used to solve the supervisors synthesis problem of discrete event systems. This work introduces a new approach, using Petri nets and the supervisory control theory, to solve the supervisor synthesis problem. To do so, two algorithms are presented, as well as a new kind of Petri nets called Petri nets with transition enabling function. The objective is to synthesize a supervisor that has the same structure of the model of the system to be controlled. Despite of powerful structuring mechanisms available in the Petri net theory for the construction of the model of complex systems, we are still likely to face the problem of state explosion when analyzing large systems. Thus, we also present a modular approach to supervisors synthesis, using two kinds of high level nets called colored Petri nets and G-Nets, respectively. Moreover, having in mind the objective of applying this approach to actual systems, we use this approach to the synthesis of faulttolerant supervisors. The application and exemplification of this presented approach is on the synthesis of supervisors for automated manufacturing systems.