On Deciding the Existence of a Liveness Enforcing Supervisory Policy in a Class of Partially Controlled General Free-Choice Petri Nets

Abstract

If there are transitions in a Petri net (PN) that cannot be prevented from firing by a supervisory policy, then we have a partially controlled PN. The existence of a liveness enforcing supervisory policy (LESP) in a partially controlled ordinary PN is undecidable. Consequently, there can be no algorithms that synthesize an LESP for an arbitrary ordinary (general) PN. In contrast, we identify a class of general free-choice PN (FCPN) structures, which strictly includes the class of ordinary FCPN structures, where the existence of an LESP in any marked member of the class is decidable.