In: The International Journal of Advanced Manufacturing Technology, 2006. 2006. URL: http://dx.doi.org/10.1007/s00170-006-0452-3.
Abstract: Effective resolution for deadlock problems plays an important role in the operation of automated flexible manufacturing systems (FMS). Based on P-invariants and elementary siphons of Petri nets, a deadlock prevention policy is developed for a special class of Petri nets that can well model many FMS. Siphons in a plant net model are divided into elementary and dependent ones. For each elementary siphon, a monitor is added to the plant model such that the siphon is invariant-controlled. Our method guarantees that no emptiable control-induced siphon is generated due to the addition of the monitors. When all elementary siphons are controlled, the controllability of a dependent siphon is ensured by properly setting the control depth variables of its related elementary siphons. An FMS example is utilized to illustrate the proposed methods.
Keywords: Deadlock prevention; Flexible manufacturing system; Petri net; Elementary siphon; P-invariant.