Monitoring and Fault-Diagnosis with Digital Clocks

Franck Cassez
IRCCyN, Nantes, France
Friday, 15 December, 2006 (All day)

We study the monitoring and fault-diagnosis problems for dense-time real-time systems, where observers (monitors and diagnosers) have access to digital rather than analog clocks. We show how, given a specification modeled as a timed automaton and a timed automaton model of the digital clock, a sound and optimal (i.e., as precise as possible) digital-clock monitor can be synthesized. We also show how, given plant and digital clock modeled as timed automata, we can check for the existence of a digital-clock diagnoser and, if one exists, how to synthesize it. Finally, we consider the problem of existence of a digital-clock such that a there is a digital-clock diagnoser.