A Hierarchical Control Simulation Model to Support Maintenance Planning in Flexible Production Systems

The manufacturing industry constantly deals with new technologies, fluctuating markets and strong competition. To stay compatible, companies continuously have to cut unit cost, improve quality, stay flexible and secure reliability. Therefore, managers need to make decisions in a dynamic, complex environment and simulation models are often used to support the decision making process. Nevertheless, the rising complexity of modern production systems is hard to capture with common simulation paradigms, as they do either not support the required flexibility, or are too complex to be applied for short-term operational usage. In this paper a hierarchical control structure is proposed to generate a generic model of a flexible production system, which captures the postulated modeling flexibility, while computational effort is still manageable. This simulation model is used to support maintenance planning in an ongoing research project, by quantifying the effects of individual machine standstills on the performance of a production system. Therefore, two quantitative metrics are proposed to describe the relationship of machine downtime and throughput of the system.