Reliable decentralized supervisory control of fuzzy discrete event systems

Decentralized supervisory control has been introduced to deal with a class of fuzzy discrete event systems (DES) in which state transitions are uncertain. In this paper, we develop the work on fuzzy DES to consider the reliable decentralized supervisor problem with possible failures of some local supervisors. By presenting a new definition of co-observable language, the reliable decentralized supervisory control problem is solved. Since the co-observable languages are not closed under union, a new normal language that is co-observable is defined to solve the synthesis problem. Finally, a numerical example is given.