The H∞ Control Problem is Solved

The H∞ control problem was posed by G. Zames in 1981 [1], and various attempts to address it had been made over the years. Ultimately, in 2006, the authors presented their solution, which is based on a tailored non-smooth optimization technique [2]. In this treatise we present the rationale of H∞ control, give a brief history, and recall the milestones reached before our 2006 solution. We clarify why our novel approach is welcomed in the high-tech and aerospace industry. Recent MATLAB functions, hinfstruct and systune, based on work by Apkarian, Noll and Gahinet (The MathWorks) are available in the Robust Control Toolbox, since R2010b and R2012b respectively.

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