Integration between process planning and scheduling using feature‐based time‐extended negotiation protocols in a multiagent system

This paper describes the adaptation of process plan with alternatives, through an operation‐based time extended negotiation protocol for decision‐making about real‐time routing of job orders of parts composed of machining operations in a job shop environment. The protocol is modified from the contract net protocol to cater for the multiple tasks and many‐to‐many negotiations. The grouping of the machining operations enables reduction of setup times, resulting from the reduction of machines changes. The time‐extended negotiation period allows the visualisation of all the times involved in the manufacture of each part, including those times that are not considered in systems of this nature, such as the negotiation times among agents. Extensive experiments have been conducted, and the performance measures, including routings, makespan and flow time, are compared with those obtained by the following approaches: traditional hierarchical approach, a cooperative coevolutionary algorithm and the search technique based on a coevolutionary algorithm.