Reduced-Order Observer for Estimating Mixed Variables in Tracking Systems under Unmatched Exogenous Disturbances


We consider the problem of designing a tracking system for nonlinear affine SISO plants under unmatched exogenous and parametric disturbances and incomplete measurements. In the framework of the block approach, we develop a discontinuous dynamic feedback control law ensuring a tracking with a given accuracy for the output variable of the command signal under the assumption of exogenous actions being smooth. The main result of the paper is a single-parameter procedure for designing a reduced-order observer with high-gain feedbacks for measurement-based estimation of the error of tracking the mixed variables used to form the feedback.

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This work was partly supported by the Russian Foundation for Basic Research, project no. 20-01-00363A.

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Correspondence to D. V. Krasnov or A. V. Utkin.

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Translated by V. Potapchouck

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Krasnov, D.V., Utkin, A.V. Reduced-Order Observer for Estimating Mixed Variables in Tracking Systems under Unmatched Exogenous Disturbances. Diff Equat 56, 1650–1663 (2020).

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