Improving sustainability in manufacturing systems using EPT-based aggregate modeling

Sustainable manufacturing includes efficient use of capital intensive manufacturing machines. For a manufacturing system to be efficiently used a trade-off has to be made between system utilization and the product flow time distribution. To be able to make this trade-off, detailed simulation models may be used. Development of such models involves much development time and maintenance. Also, measurability of critical model parameters determines the accuracy of the model. In this paper, we present a newly developed aggregate modeling method that provides a simple but accurate way to predict flow time distributions as a function of the utilization. The aggregate modeling method approximates each workstation in the manufacturing system by a single server with a workload-dependent process time distribution, and a workload-dependent overtaking distribution. Alterna- tively, we consider approximating the whole system as a single server. We present simulation experiments that show the potential of both approaches.