Supervisory control of real-time discrete event systems under bounded time constraints

An analytical framework for supervisory control of real-time discrete event systems (DESs) under bounded time constraints is presented. In order to address the bounded time constraints of the systems, timed languages based on timed transition models are introduced. Using eligible time bounds, the notions of trace-controllability and time-controllability of timed languages are proposed. Based on these notions, necessary and sufficient conditions for the existence of a supervisor for a real-time DES to achieve the given timed language specification are presented. The proposed approach shows that an exhaustive enumeration of the language generated in timed transition models is not needed to verify such existence conditions of the supervisor.