Monitoring of flexible production systems using high-level Petri net specifications

The degree of reliability in the operation of flexible production systems d epends not only on the operation of the individual components, but also on the structure and evolution of the embedded supervisory control system. Mon itoring of operations and of the behaviour of the components and of the sys tem as a whole is an essential function of such a supervisory control syste m. This paper focuses on the development and implementation of feature- and model-based monitoring methods using high-level Petri net specifications o f flexible production systems and of the embedded discrete-event controller s. The combination of machine-human interface concepts with the developed m onitoring methods leads to a user-friendly representation of monitoring inf ormation. An application at industrial level is shown by means of a case st udy, i.e., a sample flexible assembly cell, situated at the Institute for M anufacturing Automation and Production Systems, Germany. (C) 1999 Elsevier Science Ltd. All rights reserved.