Scaled relative graphs for system analysis

  title={Scaled relative graphs for system analysis},
  author={Thomas Chaffey and Fulvio Forni and Rodolphe Sepulchre},
  journal={2021 60th IEEE Conference on Decision and Control (CDC)},
Scaled relative graphs were recently introduced to analyze the convergence of optimization algorithms using two dimensional Euclidean geometry. In this paper, we connect scaled relative graphs to the classical theory of input/output systems. It is shown that the Nyquist diagram of an LTI system on L2 is the convex hull of its scaled relative graph under a particular change of coordinates. The SRG may be used to visualize approximations of static nonlinearities such as the describing function… 

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  • Computer Science
    IEEE Transactions on Automatic Control
  • 1967
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