Partially-Supervised Plants: Embedding Control Requirements in Plant Components

Supervisory control deals with automated synthesis of controllers based on models of the uncontrolled system and the control requirements. In this paper we share the lessons learned from synthesizing controllers for a patient support system of an MRI scanner regarding the specification of the control requirements. We learned that strictly following the philosophy of supervisory control, which partitions specifications in an uncontrolled plant and control requirements, may lead to unnecessarily complex specifications and duplication of information. In such cases, the specification can be substantially simplified by embedding part of the control requirements in so-called partially-supervised plants. To formalize the new concepts, we apply a recently developed processtheoretic approach to supervisory control. The new method for analysis of the models provides a better insight into their underlying behavior, which is demonstrated by revisiting the models of the industrial study.