A Note on Fault Diagnosis Algorithms

TL;DR

This paper reviews fault diagnosability algorithms for discrete-event systems and timed automata, highlighting their reduction to automata emptiness problems and summarizing complexity results.

Contribution

It establishes a unified approach to diagnosability checking for both systems and automata, extending known reductions and complexity analyses.

Findings

Diagnosability reduces to automata emptiness problems

Checking bounded diagnosability is applicable to timed automata

Provides a synthesis of complexity results for fault diagnosis

Abstract

In this paper we review algorithms for checking diagnosability of discrete-event systems and timed automata. We point out that the diagnosability problems in both cases reduce to the emptiness problem for (timed) B\"uchi automata. Moreover, it is known that, checking whether a discrete-event system is diagnosable, can also be reduced to checking bounded diagnosability. We establish a similar result for timed automata. We also provide a synthesis of the complexity results for the different fault diagnosis problems.