Optimal sensor choice for observability in free-choice Petri nets

摘要

This paper studies the optimal sensor choice for observability problem in Discrete Event Systems (DES) modeled by Interpreted Free-choice Petri Nets (IPCN). Taking advantage of the fact that, event-detectability is a necessary and sufficient condition for observability in live, cyclic and bounded IFCN, a structural characterization of event-detectability and a simple polynomial algorithm to choose a minimal cost sensor configuration for observability in this class of nets are provided. This algorithm is successfully applied to an illustrative example.