Abstract: The planning of a blade FMS is studied. Two candidate designs of blade FMSl and blade FMS2 are proposed. The Petri net model of blade FMSl that has the properties of liveness, boundedness and reversibility is constructed by using a hybrid synthesis methodology of Petri nets. The Petri net model of blade FMS2 is also constructed. As deadlock can occur in blade FMS2, a new algorithm of the deadlock avoidance is proposed. A improved evaluation criteria of FMS is established and the candidate designs are evaluated by the evaluation criteria.

Key words: Deadlocking, Flexible manufacturing system, Petri net Planning