Supervision patterns in discrete event systems

In this paper, we are interested in the diagnosis of discrete-event systems modeled by finite tranistion systems. We propose a model of supervision patterns general enough to capture past occurrences of particular trajectories of the system. Modeling the diagnois objective by supervision patterns allows us to generalize the properties to be diagnosed and to render them independent of the description of the system. We first formally define the diagnosis problem in this context. We then derive techniques for the construction of a diagnoser and for the verification of the diagnosticability based on standard operations on transition systems. We show that these techniques are general enough to express and solve in a unified way a broad class of diagnosis problems found in the literature, e.g. diagnosing permanent faults, multiple faults, faults sequences and some problems of intermittent failures.