Abstract
Petri nets are widely used to model flexible manufacturing systems (FMSs) because they can help analyze the properties and synthesize deadlock-free supervisory controllers of FMS. Weighted System of Simple Sequential Processes with Resources ((WSPR)-P-3) is an important subclass of Petri nets that can well model many FMSs. This work first gives new algorithms to check liveness for a (WSPR)-P-3 net via its subnet trees and structure. Then the computation complexity for the proposed method is shown in this paper, to be polynomial under certain limitations. Finally, sufficient conditions for deciding liveness of a (WSPR)-P-3 are established. An example is used to illustrate the results.