Supervisory control of discrete event systems with communication delays and partial observations

This paper presents necessary and sufficient conditions for the existence of a nonblocking supervisor that achieves a given language specification for a discrete event system (DES) with communication delays and partial observations. In many practical situations, some uncontrollable events can subsequently occur before a proper control action is applied to the DES due to delays in sensing, communicating, and actuating. Moreover, some of the uncontrollable events may be unobservable. To achieve a given language specification in such situations, this paper presents a language property called delay observability which assures no confliction in making a decision for legal controllable events under partial observation and delay communication.