CONTROLLABILITY OF PREDICATES AND LANGUAGES IN DISCRETE-EVENT SYSTEMS

In discrete-event systems, two control techniques, called supervisory control and state feedback logic, are applicable if control specifications are given in terms of predicates on the set of states. The concepts of controllability for both techniques has been proposed for the analysis and design of these techniques. First it is shown that controllability of the legal language for a given predicate is equivalent to that for the corresponding reachability set. Next we deal with the relationship between the supremal controllable subpredicate of the predicate and the supremal controllable sublanguage of the corresponding legal language.