A Petri Net Based Deadlock Avoidance Policy for Flexible Manufacturing Systems With Assembly Operations and Multiple Resource Acquisition

Efficient deadlock control policies are very important in the operation of flexible manufacturing systems (FMS). This paper focuses on deadlock control problems for a general class of FMS. They have three interesting characteristics from the application point of view. First, flexible routes of parts and assembly operations are allowed. Second, the number of parts of the same type in a product may be more than one. Third, an operation may require multiple resources. To characterize such FMS, a Petri net model that can deal well with all FMS characteristics is developed. Based on it, this paper proposes a Banker's-algorithm-like deadlock avoidance policy. The proposed policy is proved to be polynomial in the model size. Moreover, experimental results indicate its effectiveness and superiority over the state-of-the-art policies.