Supervisory Control of Manufacturing Systems Using Petri Nets *

Abstract The design and operation of modern industrial systems require modeling and analysis in order to select the optimal design alternative and operational policy. Discrete event system models are encountered in a variety of fields, for example computers, communication networks, manufacturing systems, sensors or actuators, faults diagnosis, robotics and traffic. The paper describes principles and methods of supervisory control of discrete event systems initiated by Ramadge and Wonham. Three supervisory control methods based on the Petri net models are introduced, and the key features of the Petri tool software application for the supervisory control of discrete event systems modeled by Petri nets are highlighted.

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Optimal Supervisory Control of Flexible Manufacturing Systems by Petri Nets: A Set Classification Approach

IEEE Transactions on Automation Science and Engineering ◽

10.1109/tase.2013.2241762 ◽

2014 ◽

Vol 11 (2) ◽

pp. 549-563 ◽

Cited By ~ 114

Author(s):

YuFeng Chen ◽

ZhiWu Li ◽

MengChu Zhou

Keyword(s):

Petri Nets ◽

Supervisory Control ◽

Flexible Manufacturing ◽

Flexible Manufacturing Systems ◽

Manufacturing Systems ◽

Classification Approach

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Optimal enforcement of liveness for decentralized systems of flexible manufacturing systems using Petri nets

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331220908999 ◽

2020 ◽

Vol 42 (12) ◽

pp. 2206-2220

Author(s):

Muhammad Bashir

Keyword(s):

Computational Complexity ◽

Petri Nets ◽

Petri Net ◽

Supervisory Control ◽

Flexible Manufacturing ◽

Flexible Manufacturing Systems ◽

Manufacturing Systems ◽

Common Elements ◽

Decentralized Controllers ◽

The Given

The decentralized supervisory structure has drawn much attention in recent years. Many studies are reported in the paradigm of automata while few can be found in the Petri net model. This paper proposes a new method for decentralized supervisory control using the Petri net paradigm. Two efficient Algorithms are developed in the proposed method. Algorithm 1 is used to compute decentralized working zones from the given LS3PR Petri net model for flexible manufacturing systems. Algorithm 2 is used to compute the decentralized controllers that enforced liveness to the decentralized working zones. The sequential assembling is used to reconnect and controlled the working zones via decentralized controllers. The decentralized controller is added to the decentralized working zones that have common elements, that is, common transitions. The proposed method has the following advantages: (i) it can be applied to a complex Petri net model for flexible manufacturing systems, (ii) the proposed methods has less computational complexity when compared with the previous methods, (iii) the proposed method can obtain a minimal number of decentralized controllers that enforce liveness of the uncontrolled Petri net model. Experimental examples are presented to explore the applicability of the proposed methods.

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