5. Conclusion and discussion

In this article, the state of the art in Discrete Event System (DES) diagnostic methods has been presented. We have seen that the majority of SED diagnostic methods use either state machines or Petri nets (RdPs) to model normal and/or faulty behavior. Automata are a formal modeling tool with composition and projection operators that enable us to move from a local view of a process to a global view, and vice versa.

In addition, the languages associated with automata provide a formal definition of the notion of diagnosability. However, the granularity of automata modeling is a determining factor, involving problems of readability and explosion of the number of states.

RdPs, on the other hand, are well-suited to dealing with event synchronization and resource sharing, since it is possible to have several tokens for a single slot, or one slot...