Robust Control pp 114-121 | Cite as

Linear systems and robustness: a graph point of view

  • Tryphon T. Georgiou
  • Malcolm C. Smith
Conference paper
Part of the Lecture Notes in Control and Information Sciences book series (LNCIS, volume 183)


This paper presents a framework for modelling and robust control of linear systems based on a graph point of view. Basic concepts such as linearity, causality, stabilizability can be defined as properties of the graph of a system. Uncertainty is naturally thought of in terms of perturbations of the graph. Modelling and approximation are also fundamentally related to the graph of the system. Robustness will be quantified in the graph setting using the gap metric. Necessary and sufficient conditions for robustness will be explained geometrically in terms of the graphs of the plant and controller. A flexible structure design example will be discussed.


Robust Control Hankel Operator Disturbance Attenuation Parallel Projection Graph Point 
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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • Tryphon T. Georgiou
    • 1
  • Malcolm C. Smith
    • 2
  1. 1.Department of Electrical EngineeringUniversity of MinnesotaMinneapolisU.S.A.
  2. 2.Department of EngineeringUniversity of CambridgeCambridgeU.K.

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