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The increasing complexity of systems and the increasing market pressure necessitate the need for methods to maximize reuse and to minimize the effort to develop new systems. Modelbased engineering is one of these methods. It uses models and model-based techniques in the development process to analyze and synthesize systems and components. In this report, Supervisory Control Synthesis is used to design a supervisory controller for a patient support system. This system is used to position a patient in a Magnetic Resonance Imaging (MRI) scanner. To improve the evolvability of the design, the uncontrolled system and the control requirements are modeled independently, using small loosely coupled minimal restrictive automata. An implementation of the synthesized supervisor is realized by means of a transformation to an automaton in the Compositional Interchange Format (CIF). The supervisor is validated by means of hardware-in-the-loop simulation, using the real patient support system.

By means of Ramadge–Wonham supervisory control theory, supervisory controllers (supervisors) can be synthesized instead of designing them manually. This chapter presents an application of supervisory control to a patient support system for MRI scanners. The design process of the controller from its requirements to its actual implementation on real hardware has been done according to the synthesis-based engineering paradigm. This paradigm integrates the model-based engineering and supervisory control paradigms. The design process is supported by a tool framework that is based on the Compositional Interchange Format for hybrid systems (CIF). An experiment conducted in the course of the case-study indicates that this design process improves the evolvability of the controller significantly.

This paper presents an application of Ramadge-Wonham supervisory control theory to a patient support system for MRI scanners. The obtained controller was implemented and tested on real hardware. A distinguishing feature of the proposed application is that the evolvability of the controller is an essential requirement. By evolvability is the ability to adapt the controller to meet modified control objectives. The experiments conducted in the course of the case-study indicate that the use of supervisory control theory improves the evolvability of the controller.

In the Model-Based Engineering (MBE) paradigm, models are the core elements in the design process of a system from its requirements to the actual implementation of the system. By means of Supervisory Control Theory (SCT), supervisory controllers (supervisors) can be synthesized instead of designingthem manually. In this paper, a framework based on the Compositional Interchange Format for hybrid systems (CIF) has been developed that integrates the MBE andthe SCT paradigms. To illustrate the framework, an industrial-size case study has been performed: 'synthesis of a supervisory controller for the patientsupport system of an MRI scanner'. In this case study, we address 1) modelling of the components and the control requirements; 2) synthesis of the supervisor;3) simulation of the synthesized supervisor and a hybrid model of the plant; and 4) real-time, simulation based control of the supervisor and the actual patient support system of the MRI scanner.

Hybrid Chi is a process algebra for the modeling and analysis of hybrid systems. It enables modular specification of hybrid systems by means of a large set of atomic statements and operators for combining these. For the efficient implementation of simulators and the verification of properties of hybrid systems it is convenient to have a model that uses a more restricted part of the syntax of hybrid Chi. To that purpose the linearization of a reasonably expressive, relevant subset of the Chi language is discussed. A linearization algorithm that transforms any specification from this subset into a so-called normal form is presented. The algorithm is applied to a bottle-filling line example to demonstrate tool-based verification of Chi models.