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Supervisory control of real-time systems using prioritized synchronization

  • Ratnesh Kumar
  • Mark A. Shayman
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1066)

Abstract

The theory of supervisory control of discrete event systems is extended to the real-time setting. The real-time behavior of a system is represented by the set of all possible timed traces of the system. This is alternatively specified using timed automata where each transition is associated with an event occurrence time set during which time the transition can occur. Our model for time is more general in that the time advances continuously as compared to a model where time advances discretely. We extend the notion of prioritized synchronous composition to the real-time setting to use it as the control mechanism. It is shown that a suitable extension of the controllability condition to the real-time setting yields a condition for the existence of a supervisor achieving a desired timed behavior. Although the real-time controllability is similar in form to its untimed counterpart, they are different in the sense that one does not imply the other and vice-versa.

Keywords

Discrete event systems timed automata real-time systems prioritized synchronization supervisory control real-time controllability real-time relative-closure 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Ratnesh Kumar
    • 1
  • Mark A. Shayman
    • 2
  1. 1.Department of Electrical EngineeringUniversity of KentuckyLexington
  2. 2.Department of Electrical Engineering and ISRUniversity of MarylandCollege Park

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