A Merging Method for Siphon-Based FMS Maximally Permissive Control with Simple Structures

It has been a hot race to design optimal controllers to be maximally permissive with fewest monitors in the shortest amount of time. Recent maximally permissive deadlock prevention controls for (SPR)-P-3 (Systems of Simple Sequential Processes with Resources) reduce the computation burden by considering only a small portion of all forbidding markings and employs much fewer monitors by a linear integer programming method. However, it still requires costly reachability analysis. This paper proposes a method (the first of its kind) to merge several monitors into a single one while not losing states. It achieves the same best results in the literature while avoiding the time-consuming reachability analysis which does not scale well with the size of the nets.