The use of the Petri net reduction approach for an optimal deadlock prevention policy for flexible manufacturing systems

Abstract

In a flexible manufacturing system (FMS) with multiple products, deadlocks can arise due to limited shared resources, such as machines, robots, buffers, fixtures etc. The development of efficient deadlock prevention policies, which can optimise the use of system resources, while preventing deadlocks from occurring, has long been an important issue to be addressed. In [1], an optimal deadlock prevention policy was proposed, based on the use of reachability graph (RG) analysis of the Petri net model (PNM) of a given FMS and the synthesis of a set of new net elements, namely places with initial marking and related arcs, to be added to the PNM, using the theory of regions. The policy proposed in [1] is optimal in the sense that it allows the maximal use of resources in the system according to the production requirements. For very big PNMs, the reachability graph of the PNMs becomes very large and the necessary computations to obtain an optimal deadlock prevention policy become more difficult. In this paper, we propose the use of the Petri net reduction approach to simplify very big PNMs so as to make necessary calculations easily in order to obtain an optimal deadlock prevention policy for FMSs. An example is provided for illustration.

Synthesis of feedback control elements for discrete event systems using Petri net models and theory of regions

“…When the synthesised feedback elements (atomic nets), given in Tables 16,17,18,19,20,21 and 22, for zone1, zone 2, zone 3 and zone 4, respectively, are added to the UPNM, the controlled Petri net model (CPNM) is obtained as shown in Fig. 10.…”

“…Note that the use of the theory of regions has recently been reported in the context of deadlock prevention [16,17] and supervisory control [18]. In the former, an optimal deadlock prevention policy for flexible manufacturing systems was proposed using Petri net models and the theory of regions.…”

Deadlock analysis and control based on Petri nets: A siphon approach review

“…Deadlock avoidance 4,11,12,15,48,53,54,56,57,73,106,107,109,[122][123][124][125][126][127][128][129][130][131][132][133][134][135][136]319 is a resources allocation mechanism, behind which an online control policy is used to make a correct decision to proceed among the feasible evolutions. Deadlock prevention 6,49,71,72,75,77,82,91,[95][96][97][98]103,111,[137][138][139][140][141][142][143][144]…”

A Siphon-based Deadlock Prevention Policy for a Class of Petri Nets - S3PMR

“…Monitors or control places and related arcs are often used to achieve such purposes Ezpeleta et al [1995], , Li and Zhou [2004], Huang et al [2001], Chao [2006], , and Uzam [2004]. The work of Ezpeleta et al [1995] is usually considered to be the first using structure theory of Petri nets to design monitor-based liveness-enforcing Petri net supervisors for FMS.…”