Petri Net Based Synthesis Method to Construct Optimal Controllers and Its Application to a Jobshop Scheduling

Deadlock prevention, deadlock detection, and deadlock avoidance strategies are used to solve the deadlock problems of Flexible Manufacturing Systems (FMS). The theory of regions has been recognized as the unique method for obtaining maximally permissive controllers in the existing literature. All legal and live maximal behavior of a Petri net model can be preserved by using a Marking/Transition-Separation Instance (MTSI). However, obtaining all sets of MTSIs is an extremely time consuming problem. This work proposes Crucial Marking/Transition-Separation Instances (CMTSIs) that allow designers to employ few MTSIs to deal with deadlocks. The advantage of the proposed policy is that a maximally permissive controller can be obtained with drastically reduced computation. Experimental results, by varying the markings of given net structures, indicate that it is the most efficient policy to obtain optimal controllers among existing methods based on the theory of regions.

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A two-step ACO-PSO approach to optimize flexible jobshop scheduling of air compressor based on Petri net model

International Technology and Innovation Conference 2006 (ITIC 2006) ◽

10.1049/cp:20060773 ◽

2006 ◽

Cited By ~ 1

Author(s):

Zhong Meipeng ◽

Pan Xiaohong

Keyword(s):

Petri Net ◽

Air Compressor ◽

Jobshop Scheduling ◽

Flexible Jobshop

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Liveness and boundedness analysis of Petri net synthesis

Mathematical Structures in Computer Science ◽

10.1017/s0960129512000515 ◽

2014 ◽

Vol 24 (5) ◽

Author(s):

CHUANLIANG XIA

Keyword(s):

Petri Nets ◽

Petri Net ◽

Flexible Manufacturing ◽

Manufacturing System ◽

Flexible Manufacturing System ◽

Dynamic Properties ◽

Synthesis Method ◽

Sufficient Conditions ◽

Sufficient And Necessary Conditions ◽

Petri Net Synthesis

We provide motivation for and then study the synthesis of Petri nets. Synthesis can avoid the state exploration problem by guaranteeing correctness for the Petri net. We propose conditions to be imposed on a synthesis shared pb-type subnet for systems specified in Petri nets that ensure the preservation of the liveness and boundedness structural properties. Specifically, we propose a group of sufficient conditions, or both sufficient and necessary conditions, for liveness preservation and boundedness preservation. Possible applications of this synthesis method are illustrated through an example in the form of a flexible manufacturing system. These results are useful for studying the static and dynamic properties of Petri nets for analysing the properties of large complex systems.

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