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arXiv · 2501.03894

Robust Moving-horizon Estimation for Nonlinear Systems: From Perfect to Imperfect Optimization

Angelo Alessandri
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Abstract

Robust stability of moving-horizon estimators is investigated for nonlinear discrete-time systems that are detectable in the sense of incremental input/output-to-state stability and are affected by disturbances. The estimate of a moving-horizon estimator stems from the on-line solution of a least-squares minimization problem at each time instant. The resulting stability guarantees depend on the optimization tolerance in solving such minimization problems. Specifically, two main contributions are established: (i) the robust stability of the estimation error, while supposing to solve exactly the on-line minimization problem; (ii) the practical robust stability of the estimation error with state estimates obtained by an imperfect minimization. Finally, the construction of such robust moving-horizon estimators and the performances resulting from the design based on the theoretical findings are showcased with two numerical examples.

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Angelo Alessandri. 2025-01-07. Robust Moving-horizon Estimation for Nonlinear Systems: From Perfect to Imperfect Optimization. https://arxiv.org/abs/2501.03894

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