Fault-tolerant robust supervisor for discrete event systems with model uncertainty and its application to a workcell

This paper addresses the problem of fault-tolerant robust supervisory control of discrete event systems (DES) with model uncertainty. Necessary and sufficient conditions for the existence of a fault-tolerant robust supervisor are derived. If the conditions are satisfied, then tolerable fault event sequences embedded in the system can be achieved. The results obtained are applied to design, modeling, and control of a workcell in a production line consisting of two gas metal arc welding (GMAW) robots, a sensor, and a conveyor.