Combined Supervisor Synthesis for Enforcing GMECs on a Controlled Petri Net

A combined supervisor synthesis method is addressed to solve a class of control problems. It is to enforce a conjunction of general mutual exclusion constraints on a controlled Petri nets where the uncontrollable influence subnets are forward synchronization and forward conflict free (FSFCF) nets. Firstly, the method is presented to design the observer places; Secondly, the necessary and sufficient condition of the existence of supervisor and the method to synthesize the optimal supervisor are proposed using the markings of the observer places; Lastly, an example is given to illustrate the theoretic results.