Separation model design of manufacturing systems using the distributed agent-oriented Petri net

Manufacturing systems are hardly modelled and analysed in detail due to the complex and interactive behaviours of the production, movement, maintenance and dispatch on the shopfloor. In this paper, an agent-based modelling methodology is proposed to model the manufacturing systems using the separation model design approach. The agent models are constructed using the distributed agent-oriented Petri net (DAOPN). The DAOPN is a high-level Petri net (PN) and is designed based upon the coloured time Petri net (CTPN). The new designed DAOPN is especially desired to model the manufacturing systems in the separation and decomposition manners to reduce the modelling efforts and increase the modelling extensibility. The proposed DAOPN components include the immediate, pitch-type, catch-type, status-source and status-duplication places; immediate, timed, decision and database-accessing transitions; and directed, inhibitor and interrupt arcs. In addition to the separation characteristics, the DAOPN can also model manufacturing systems with flexible routes of products, flexible automation of equipment, product model mixes, and huge production information intercommunication. Especially, the separation design is advantageous to the manufacturing model reconstruction and maintenance. Finally, the DAOPN is defined in this paper, and several typical applications including the production, movement, equipment failure and preventive maintenance are all discussed and evaluated.