Abstract:
Many complex systems in different areas such as
manufacturing, telecommunications or transportation can be
modeled as discrete event systems (DES). In this paper, we
consider the fault diagnosis for DES which is concerned with
detecting fault occurrences in a DES within a bounded number
of event occurrences by a diagnoser automaton. Hereby, such
diagnoser is able to observe a subset of the system events and
the maximum required number of event occurrences until a fault
detection is denoted as the worst case detection delay (WCDD).
The main contribution of the paper is an approach for reducing
the number of required observations for fault diagnosis without
increasing the WCDD. As a result, it is possible to determine
a diagnoser with a small size which is essential in practical
applications. We first develop an algorithm for computing the
WCDD and then adapt an approach for the reduction of the
observable event set in order to obtain a reduced diagnoser. The
application of our method to a communication system example
demonstrates its practicability.