Abstract
In this paper, we review some recent results on supervisory control of partially observed discrete event systems. In order to solve a nonblocking supervisory control problem, we need to compute an Lm(G)-closed, controllable, and observable sublanguage of a given specification language. We present an algorithm for computing such a sublanguage which is larger than the supremal Lm(G)-closed, controllable, and normal sublanguage. We also consider a problem to find an observable event set with minimum cardinality which guarantees observability. The problem is computationally hard since its corresponding decision problem is NP-complete.
