Decentralized Diagnosability Analysis of Discrete Event Systems using Petri Nets

In this paper we present a procedure to analyze the diagnosability of a Petri net system in a decentralized framework. We recall the denition of failure ambiguous strings, i.e., strings that can be both faulty or not in the decentralized case, while can be distinguished in a centralized framework. We rst prove that the absence of such kind of strings guarantees that the system is diagnosable in a decentralized framework. Then, we give an ecient procedure to verify the absence of such kind of strings for both bounded and unbounded Petri net systems. A computational complexity analysis of such procedure is also presented.