Combinatorial optimization models for production scheduling in automated manufacturing systems

Production planning and scheduling models arising in automated manufacturing environments exhibit several features not encountered in models developed for traditional production systems. For instance, models of automated facilities typically include tooling constraints which reflect the possibility for a machine to use different tools in order to perform successive operations, within limits imposed by the size of the tool magazine. Also, these models often account for the existence of flexible material handling systems whose activities must be synchronized with the machining operations in order to optimize system utilization. In this paper, we describe a few interesting combinatorial optimization problems proposed in this framework, we point to their relationships with models investigated in seemingly remote areas, and we identify a number of challenging open problems.