Some tractable supervisory control problems for discrete-event systems modeled by Buchi automata

Discrete-event systems (DES) are modeled by Buchi automata together with a means of online control. In this setting the concept of a controllable language is extended to infinite strings, and conditions for the existence of a supervisor (controller) to implement a prescribed closed-loop behavior are derived. The focus is on a class of DES called product systems. These are DES composed of a finite set of asynchronous components. A control problem for such a system typically requires the synthesis of an online controller so as to achieve some prescribed coordinated behavior of the component subsystems. One of the principal difficulties in this task is that the size of the state space increases exponentially with the number of components. It is shown that despite this fact several interesting control synthesis problems for such systems are computationally feasible, and algorithms are developed for solution