Modeling Framework for Automated Manufacturing Systems Based on Petri Nets and ISA Standards

This work presents a systematic methodology to model Automated Manufacturing Systems using Petri Nets. The modelling strategy consists in the definition and the interconnection of some generic Petri Net models applied to the discrete-event dynamic behaviour of the equipments and its procedures. It is based on the industrial standards ISA-88 and ISA-95, where the classification of equipment and the definition of their generic process tasks are suggested, separately of the product manufacturing recipes. The approach provides a formal and ordered methodology to study industrial automated systems where the equipment availability, storage limitations, sharing resources and logic precedence between process tasks appear in the Petri model. A complete case of study related to an automated cell is presented which includes a network of PLC's and industrial robots.