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arXiv · 2112.02939

State Observation of Affine-in-the-States Systems with Unknown Time-Varying Parameters and Output Delay

Alexey Bobtsov·Nikolay Nikolaev·Romeo Ortega·Denis Efimov·Olga Kozachek
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Abstract

In this paper we address the problem of adaptive state observation of affine-inthe-states time-varying systems with delayed measurements and unknown parameters. The development of the results proposed in the [Bobtsov et al. 2021a] and in the [Bobtsov et al. 2021c] is considered. The case with known parameters has been studied by many researchers (see [Sanz et al. 2019, Bobtsov et al. 2021b] and references therein) where, similarly to the approach adopted here, the system is treated as a linear time-varying system. We show that the parameter estimation-based observer (PEBO) design proposed in [Ortega et al. 2015, 2021] provides a very simple solution for the unknown parameter case. Moreover, when PEBO is combined with the dynamic regressor extension and mixing (DREM) estimation technique [Aranovskiy et al. 2016, Ortega et al. 2019], the estimated state converges in fixed-time with extremely weak excitation assumptions.

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Alexey Bobtsov, Nikolay Nikolaev, Romeo Ortega, Denis Efimov, Olga Kozachek. 2021-12-06. State Observation of Affine-in-the-States Systems with Unknown Time-Varying Parameters and Output Delay. https://arxiv.org/abs/2112.02939

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