Decentralized failure diagnosis for discrete-event systems with costly communication between diagnosers

Reliable supervisory control of engineering systems requires failure diagnosis algorithms for discrete-event systems. For large, modularly designed plants, such as communication networks, robustness considerations and limitations on the communication between local sensors lead to decentralized implementations of failure diagnosis algorithms. A trade-off has to be made between the speed of diagnosis and the cost of communication and computation. An algorithm is proposed for decentralized failure diagnosis with asymmetric communication in which Diagnoser 2 estimates also the observer state of Diagnoser 1 and sends only that subset of failure states which is relevant for the other diagnoser when this is useful for Diagnoser 1's control task of failure detection and diagnosis. This algorithm can help in suggesting practically implementable heuristic algorithms.