Agent-based distributed scheduling for virtual job shops

Nowadays, market globalisation and stiff world-wide competition require flexible, demand-driven, and reconfigurable production systems that can adapt to the requirements of the increasing reduction in product life cycle and rapid changes in market demand. The advent and development of network technology (especially the Internet) and distributed computing technology make it possible for geographically dispersed manufacturing resources to be integrated and deployed effectively and efficiently. In addition, manufacturing enterprises can expand their throughput within a short time and rapidly reduce the production cycle via transferring certain jobs to other available manufacturing resources in the globalised manufacturing environment, viz., manufacturing enterprises can expand their throughput through the dynamic formation of virtual job shops according to the production requirements. Owing to more open manufacturing environments and rapid changes of market demands, the traditional centralised scheduling approaches are not suitable for this open distributed manufacturing environment. This paper proposes a distributed scheduling approach in which a multi-agent solution towards a 'task-machine' assignment is presented. The main points of discussion are the formation of a virtual job shop that is based on market mechanism and the distributed scheduling approach based on negotiation.