Minimizing setups and time-related objectives on multiple machines

Manufacturing companies use several tools on multiple machines during the pro- duction process. Tool characteristics, generalized in tool sets, prevent a particular tool from being installed on incompatible machines. However, tool generalization provides less detailed schedules. These schedules are conceived as timetables, as a result of the problems' xed time characteristics. General and specic constraints for tools and tool sets, in combination with a makespan objective, are considered while constructing schedules. In practice these schedules are constructed manually and are thus limited to a period of up to two weeks (short term), leaving room for improvement. This work presents techniques for generating long term (mul- tiple weeks or months) feasible solutions, focusing on multiple objectives. A late acceptance heuristic consisting of swap moves has been developed and tested on benchmark data. In addition, a prototype decision support tool has been developed and approved by practitioners.status: publishe