Petri nets synthesis for modeling FMS: A review

This paper presents a review of synthesis techniques for Petri net modeling of Flexible Manufacturing Systems. Top-down methods, or stepwise refinement of transitions and places, have the advantage that the system is viewed totally, but they are difficult to apply to systems with highly shared resources. Bottom-up methods, or modular composition, consisting of the merging of places and sharing of simple elementary paths, have the advantage that the subsystems have real life correspondences. However, the global system may not show the same properties as the subsystems. Hybrid techniques using Top-down methods initially and Bottom-up methods finally, combine the advantages of both methods.