SEQUENTIAL MODELING OF THE PLANNING AND SCHEDULING PROBLEMS OF FLEXIBLE MANUFACTURING SYSTEMS

Research on the planning and scheduling issues of flexible manufacturi ng systems (FMS) has not been sparse. Most, if not all, studies, howev er, have focused on either developing the planning model or examining the performance of different scheduling rules. To date, the FMS planni ng and scheduling problems have not been studied together, though they are highly interrelated. This paper takes a first step to simultaneou sly address the planning and scheduling problems of flexible manufactu ring systems. The problems are solved as a hierarchical process. We fi rst integrate and formulate batching, loading, and routeing, three of the most important FMS planning problems, as a 0-1 mixed integer progr am. According to the optimal decisions provided by the integrated plan ning model, we then develop an off-line scheduling scheme that is capa ble of generating detail parts sequencing in the sequence independent environment (i.e. the operations are not constrained by a process sequ ence). Finally, we suggest several extensions and future research dire ctions.