Coupling event domain and time domain models of manufacturing systems

Manufacturing systems are often characterized as discrete event systems (DES) and consequently, these systems are modeled with discrete event models. For certain discrete event modeling paradigms, control theory/techniques have been developed in event domain. However, from a control or performance perspective, a lot of notions are time related, like stability, settling time, transient behavior, throughput, flow time, efficiency, etc. Moreover, if we also consider market/customer requirements, almost all requirements are within time perspective: due dates, deliverability, earliness, tardiness, etc. Therefore, it is also useful to have time driven models of manufacturing systems. To combine the insights in modeling and control obtained in both time and event domain, it is useful to create a coupling between those two domains. This paper describes modeling techniques in both time domain and event domain for a class of manufacturing systems and establishes a generic coupling between two model descriptions. The coupling exists of two maps between the models' states, enabling real-time control of manufacturing systems.