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Main Authors:	Glushchenko, Anton, Lastochkin, Konstantin
Format:	Preprint
Published:	2024
Subjects:	Systems and Control
Online Access:	https://arxiv.org/abs/2403.11076
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author	Glushchenko, Anton Lastochkin, Konstantin
author_facet	Glushchenko, Anton Lastochkin, Konstantin
contents	In adaptive control theory, the dynamic regressor extension and mixing (DREM) procedure has become widespread as it allows one to describe major of adaptive control problems in unified terms of the parameter estimation problem of a regression equation with a scalar regressor. However, when the system/parameterization is affected by perturbations, the estimation laws, which are designed on the basis of such equation, asymptotically provides only biased estimates. In this paper, based on the bias-eliminated least-squares (BELS) approach, a modification of DREM procedure is proposed to annihilate perturbations asymptotically and, consequently, asymptotically obtain unbiased estimates. The theoretical results are supported with mathematical modelling and can be used to design adaptive observers and control systems.
format	Preprint
id	arxiv_https___arxiv_org_abs_2403_11076
institution	arXiv
publishDate	2024
record_format	arxiv
spellingShingle	Unbiased Parameter Estimation via DREM with Annihilators Glushchenko, Anton Lastochkin, Konstantin Systems and Control In adaptive control theory, the dynamic regressor extension and mixing (DREM) procedure has become widespread as it allows one to describe major of adaptive control problems in unified terms of the parameter estimation problem of a regression equation with a scalar regressor. However, when the system/parameterization is affected by perturbations, the estimation laws, which are designed on the basis of such equation, asymptotically provides only biased estimates. In this paper, based on the bias-eliminated least-squares (BELS) approach, a modification of DREM procedure is proposed to annihilate perturbations asymptotically and, consequently, asymptotically obtain unbiased estimates. The theoretical results are supported with mathematical modelling and can be used to design adaptive observers and control systems.
title	Unbiased Parameter Estimation via DREM with Annihilators
topic	Systems and Control
url	https://arxiv.org/abs/2403.11076

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