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Robust Control in Gap Metric

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Encyclopedia of Systems and Control

Abstract

Robust control needs to start with a model of system uncertainty. What is a good uncertainty model? First it needs to capture the possible system perturbations and uncertainties. Second it needs to be mathematically tractable. The gap metric was introduced by Zames and El-Sakkary for this purpose. Its study climaxed in an award-winning paper by Georgiou and Smith. A modified gap, called the ν-gap, was later discovered by Vinnicombe and was shown to have advantages. With these metrics in hand, robust stabilization issues can be nicely addressed.

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Author information

Authors and Affiliations

  1. Hong Kong University of Science and Technology, Hong Kong SAR, China

    Li Qiu

Authors
  1. Li Qiu
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Editor information

Editors and Affiliations

  1. Mechanical Engineering, Electrical and Computer Engineering, Boston University, Boston, MA, USA

    John Baillieul

  2. Honeywell Automation and Control Solutions, Golden Valley, MN, USA

    Tariq Samad

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© 2015 Springer-Verlag London

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Qiu, L. (2015). Robust Control in Gap Metric. In: Baillieul, J., Samad, T. (eds) Encyclopedia of Systems and Control. Springer, London. https://doi.org/10.1007/978-1-4471-5058-9_165

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