Discrete Event Dynamic Systems

, Volume 12, Issue 3, pp 335–377 | Cite as

A General Architecture for Decentralized Supervisory Control of Discrete-Event Systems

  • T.-S. Yoo
  • Stéphane Lafortune
Article

Abstract

We consider a generalized form of the conventional decentralized control architecture for discrete-event systems where the control actions of a set of supervisors can be “fused” using both union and intersection of enabled events. Namely, the supervisors agree a priori on choosing “fusion by union” for certain controllable events and “fusion by intersection” for certain other controllable events. We show that under this architecture, a larger class of languages can be achieved than before since a relaxed version of the notion of co-observability appears in the necessary and sufficient conditions for the existence of supervisors. The computational complexity of verifying these new conditions is studied. A method of partitioning the controllable events between “fusion by union” and “fusion by intersection” is presented. The algebraic properties of co-observability in the context of this architecture are presented. We show that appropriate combinations of fusion rules with corresponding decoupled local decision rules guarantee the safety of the closed-loop behavior with respect to a given specification that is not co-observable. We characterize an “optimal” combination of fusion rules among those combinations guaranteeing the safety of the closed-loop behavior. In addition, a simple supervisor synthesis technique generating the infimal prefix-closed controllable and co-observable superlanguage is presented.

supervisory control decentralized architectures decision fusion computational complexity supervisor synthesis 

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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • T.-S. Yoo
    • 1
  • Stéphane Lafortune
    • 1
  1. 1.Department of Electrical Engineering and Computer ScienceThe University of MichiganAnn ArborU.S.A.

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