Design of switching supervisors for reactive class discrete event systems Information Control Problems in Manufacturing
Résumé
Based on the decentralized supervisory control, Lin and Wonham (1988), Lafortune et al. (2001), the present paper proposes a contribution to the supervisory control of systems (with different production objectives) that react to exceptional events (failure events for instance). Existing work on decentralized control of Discrete Event Systems (DES) focuses on problems where each decentralized control supervisor controls and observes some events in a system and must together achieve some prescribed goals Rudie and Wonham (1992), Yoo and Lafortune (2002). In this model the supervisors act simultaneously on the plant (process) and are sometimes conflicting. Our approach is based on the concept of decentralized control and we propose a procedure which allows in one hand to avoid the conflict problem and on the other hand to manage the commutation (switching) between two operating modes: nominal and degraded modes labelled respectively N and D. The developed control strategy for tackle the conflict problem and for manage the switching between two operating modes will be also implemented by the automata.