A Petri net model and a general method for on- and off-line multi-resource shop floor scheduling with setup times

This paper presents a Petri net model in the framework of a general method for on-line scheduling in a job shop environment with multi-resource requirements and setup times. The Petri net is based on a precise characterization of significant states, decisions and events for on- and off-line scheduling. A set of solutions to a static scheduling problem represented by an acyclic directed graph is assumed to be predetermined, as input of the proposed decision support system for shop floor scheduling. This system takes account of occurring events to suggest the appropriate scheduling decisions in real time and update the set of solutions accordingly.