An O(n2) Algorithm for Supervisor Reduction/Localization of Discrete-Event Systems

Abstract In this paper we propose a fast algorithm for supervisor reduction/localization of discrete-event systems. Supervisor reduction/localization is based on merging pairs of states of the supervisor that are control consistent. Our proposed algorithm employs two new lists – a mergeable list and a non-mergeable list – which store state pairs that have been confirmed to be control consistent or inconsistent, respectively. With these two lists, our algorithm eliminates any repeated control consistency checks, and guarantees that every state pair will be checked at most once. The time complexity of our new algorithm is O(n2), where n is the number of states of the supervisor; this improves all previously known results on supervisor reduction/localization algorithms.