Finite-Time stabilization of linear systems with unknown control direction via Extremum Seeking

TL;DR

This paper introduces a novel extremum seeking-based method for finite-time stabilization of linear systems with unknown control directions, ensuring system states stay within a time-varying hyper-ellipsoid.

Contribution

It develops a modified extremum seeking algorithm that guarantees finite-time stability for linear systems with unknown control directions, using oscillatory inputs and differential LMIs.

Findings

Proposes a new extremum seeking control approach for finite-time stabilization.

Provides a minimum dithering frequency estimate for stability.

Validates effectiveness through numerical examples.

Abstract

In this paper the finite-time stabilization problem is solved for a linear time-varying system with unknown control direction by exploiting a modified version of the classical extremum seeking algorithm. We propose to use a suitable oscillatory input to modify the system dynamics, at least in an average sense, so as to satisfy a Differential Linear Matrix Inequality (DLMI) condition which in turns guarantees that the system's state remains inside a prescribed time varying hyper-ellipsoid in the state space. The finite-time stability (FTS) of the averaged dynamics implies the FTS of the original system, as the distance between the original and the averaged dynamics can be made arbitrarily small by choosing a sufficiently high value of the dithering frequency used by the extremum seeking algorithm. An estimate of the necessary minimum dithering/mixing frequency is provided, and the effectiveness of the proposed finite-time stabilization approach is analysed by means of numerical examples.