A comparison of deadlock avoidance policies in flexible manufacturing systems

Flexible manufacturing systems are prone to deadlock, which may result in costly delays. Deadlock can be defined as a state where there is some blockage in the system that leaves resource requests unanswered forever unless there is outside intervention. We compare the performance of several deadlock avoidance policies in conjunction with scheduling rules as well as gauging the impact of due date tightness on the system performance. Results indicate that the deadlock avoidance policy factor has much more impact on the system performance than the scheduling rule factor. We suggest several deadlock avoidance policies to be used by production managers depending on their desired system performance and shop environment. The results also indicate that production managers should generally utilize the scheduling rule that is easiest to implement in their system.