A Cyber–Physical Systems-Based Double-Layer Mapping Petri Net Model for Factory Process Flow Control

Abstract

This study is concerned with the imperfect virtual-reality mapping relationship in cyber–physical systems (CPSs) and the challenge faced in knowledge-based decisions. Regarding those problems, a double-layer mapping Petri net (DMPN) model is proposed. By deploying the programmable automation gateway PAG200, combining the CPS technology with the principle of Petri net and establishing the monitoring Petri net in the cyber space, this model realizes mapping between the physical entity and the digital object. Meanwhile, the knowledge-based decision problem in CPS is defined as a Petri net conflict. In accordance with this, a control network for resolving the conflict is established. Finally, through a practical case, the workflow of DMPN is illustrated and a task allocation algorithm and a quality decision algorithm are proposed to resolve Petri net conflicts. Consequently, it is proven that DMPN is feasible in solving actual production process flow control. At the same time, it also provides a solution for enterprise workflow analysis.