This dissertation investigates the application of Petri nets in modeling and deadlock control of flexible manufacturing systems (FMS). Resource shared FMS was discussed in many papers by supposing that only one the number of resources is used at each state of a working process (WP). In this dissertation, we discuss the compound-shared- resource FMS in which multiple the number of resources can be used at each state of a WP. The main contributions of this dissertation include: 1) A Petri net model called extended S3pR (E-S~PR) is established to describe the compound-shared-resource FMS. The descriptive ability of E-S3pR is much stronger than the models based on the shared resource FMS. 2) Based on E-S3pR, we discuss the structure properties of the compound-shared-resource FMS including boundedness, liveness and reversibility. The sufficient and necessary condition of the liveness of compound-shared-resource FMS is proved. An algorithm is given for detecting deadlock structures, and a policy for deadlock prevention is proposed. Since this algorithm examines only the net structure, its computation time does not increase as the initial marking increases. So this algorithm appears to be more efficient than others, especially when the initial marking is large. 3) A new method for modeling FMS called OOPN is presented. In this method, different resources and WP of FMS are modeled respectively to obtain different object sub-nets. The model of the whole system is gained through the synchronous synthesis of all the object sub-nets. This modeling method is a modular and object oriented approach. 4) Based on OOPN, an OOPN modeling software is developed. It provides two functions lacking in other tools. One is the management of Petri nets project, and the other is a modeling tool of Petri nets for FMS. This software is not only the application of the theory proposed in this dissertation, but also a strongly demonstration of the theory.
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