Supervisory control with partial observations

Abstract

A natural generalization of the control paradigm explored so far allows for feedback in which information may be lost in the channel linking plant to controller. It will be assumed that the channel behaves like a natural (zero-memory) projection, transmitting observable and erasing unobservable events symbol by symbol. A concept of language observability is introduced to express that control decisions based on such partial feedback information are always correct. It is shown that control synthesis of a given language is possible just when the language is controllable and observable; constructive procedures are provided to design and implement the resultant feasible controller. It is then effectively computable how control performance depends on the information available to the supervisor, as parametrized by the subset of observable events.