Marking Diagnosis in Labeled Petri Nets Using Basis Diagnosers

This paper studies the marking diagnosis problem in labeled Petri nets, i.e., to determine whether a plant has reached a given set of faulty markings or not in the past, from the observation history. We observe that the conventional basis reachability graphs cannot be used for marking diagnosis due to the existence of partially faulty basis markings. To overcome such a problem, we propose a notion called the diagnostic basis partition such that the corresponding basis reachability graphs does not contain any partially-faulty basis markings. By properly selecting a set of explicit transitions, a diagnostic agent is synthesized to perform the online diagnosis.