On the invariance property of reduced supervisors from the perspective of vector discrete-event systems
Ting Jiao, Ru Chang, Xueli Nan · International Journal of Control · 2020
The relabelling mechanism is employed in symmetric discrete-event systems to obtain a control-equivalent supervisor in the relabelled level. If we apply procedure supreduce to this supervisor, with buffer sizes fixed, the result is a reduced supervisor independent of the numbers of components in each group of symmetric discrete-event systems. In this paper, we show the invariance property of reduced supervisors by utilising the semantics of vector discrete-event systems. Namely, a control congruence is generated based on the results to achieve optimal supervisory control of vector discrete-event systems. The approach is applied to two representative manufacturing facilities.