[DB 12] On Intrinsically Live Structure of a Class of Generalized Petri Nets Modeling FMSConférence Internationale avec comité de lecture : 11th International Workshop on Discrete Event Systems - WODES 2012, October 2012, pp.187-192, Series IFAC,
Mots clés: Flexible manufacturing system (FMS), Petri nets, structural liveness, circuit, weight.
Résumé: From the perspective of structure theory, the deadlock control and liveness-enforcement are mostly implemented based on siphons in most existing work. In our previous work, a kind of intrinsically live structures is proposed in a class of generalized Petri nets, weighted S3PR (WS3PR). The livenessenforcement is achieved by analyzing the structure including weight information and reconfiguring the initial marking of resource places without considering the initial token counts in idle places. In this work, the method is extended to a more general subclass than WS3PR. Instead of siphons, a new concept of structural objects is defined to carry weight information and reflect the circular waits of resources. The numerical relationship between initial markings of resource places and weighs of arcs is investigated to yield an intrinsically live structure-based liveness-enforcing method that requires no external monitors. The work provides an insight into structures of generalized Petri nets and a new angle of the deadlock control. Several examples are used to illustrate this method.
Commentaires: to be published in IFAC-PapersOnLine