Integrating Manufacturing Process Planning with Scheduling via Operation-Based Time-Extended Negotiation Protocols Izabel Cristina Zattar a 1 , João Carlos Espindola Ferreira a , João Gabriel Ganacin Granado a and Carlos Humberto Barreto de Sousa a a Universidade Federal de Santa Catarina, Departamento de Engenharia Mecânica, GRIMA/GRUCON, Florianópolis, SC, Brasil. Abstract. It is proposed in this paper the on-line adaptation of process plan with alternatives, through the application of 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. For each part, all feasible routings are considered as alternative process plans, provided the different manufacturing times in each machine are taken into account. The time-extended negotiation period allows the visualization of all of 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 in the system, and the performance measures, including routings, makespan and flow time, are compared with those obtained by the search technique based on the co- evolutionary algorithm. Keywords. Negotiation protocol, Agent technology, Planning and scheduling 1 Introduction A large obstacle for the integration between process planning and production scheduling, in dynamic manufacturing environments, is the lack of flexibility for the analysis of alternate resources when allocating the jobs in the shop floor. According to Shen et al. [4], the integration problem of manufacturing process planning and scheduling becomes even more complex when both process planning and manufacturing scheduling are to be done at the same time. This paper will describe a multiagent system with a heterarchical structure for making decisions 1 Universidade Federal de Santa Catarina, Departamento de Engenharia Mecânica, GRIMA/GRUCON, Caixa Postal 476, CEP 88040-900, Florianópolis, SC, Brazil; Tel: +55 (48) 3721-9387 extension 212; Fax: +55 (48) 3721-7615; Email: izabel.zattar@gmail.com; http://www.grima.ufsc.br