Manufacturing cell supervisory control-a modular timed discrete-event system approach

An approach to the design of modular supervisory control strategies based on a framework for the modeling and supervisory control of discrete-event systems is presented. As for centralized supervision, the approach allows the consideration of logic-based specifications, control-enforcement-related constraints, and temporal and utility optimality behavioral specifications. It yields modular supervisory control strategies that are least restrictive within given specifications, and which are correct by construction and offers all the advantages of distributed control. Under given conditions, modular supervision based on the techniques presented is equivalent to centralized supervision based on the techniques presented by B.A. Brandin et al. (1992) and by B.A. Brandin and W.M. Wonham (1993). A small manufacturing cell example illustrates the results presented