Centralized and decentralized supervisory control of nondeterministic systems under partial observation

In this paper we extend our earlier work on supervisory control of nondeterministic systems using prioritized synchronization as the mechanism of control and trajectory model as the modeling formalism by considering design of supervisors under partial observation. We introduce the notion of observation-compatible systems and show that prioritized synchronous composition (PSC) of observation-compatible systems can be used as a mechanism of control of nondeterministic systems under partial observation in presence of driven events. Necessary and sufficient conditions that depend on the trajectory model as opposed to the language model of the plant are obtained for the existence of centralized as well as decentralized supervision. Our work on centralized control shows that the results of the traditional supervisory control can be ''extended'' to the above setting, provided that the supervisor is deterministic and the observation mask is projection type. On the other hand, our work on decentralized control is based on a new relation between controllability, observability, co-observability, and PSC that we derive in this paper.