Task negotiation for distributed manufacturing systems

This paper deals with a new architecture and negotiation protocol for the dynamic scheduling of manufacturing systems. The architecture is based on the paradigm of distributed intelligence and multi-agent systems. What concerns the architecture is the existence of agents representing the tasks together with agents representing the resources. The well known contract net protocol has been adapted to handle the temporal constraints, namely the deadline submission. The purpose of this protocol is to dynamically assign operations to the resources of the manufacturing system in order to accomplish the proposed tasks. This protocol involves a renegotiation phase whenever exceptions appear. It also deals with conflict situations, namely with the case of the “indecision problem”. The approach proposed assume that deadlines are the most important constraints to consider, thus the acceptance or refuse of a resource for a specific operation depends on the capability of executing the operation in the specified deadline