Angular velocity nonlinear observer from single vector measurements

TL;DR

This paper introduces a nonlinear observer that estimates a rigid body's angular velocity using only single vector measurements, eliminating the need for attitude data or rate gyros, with proven convergence and simulation validation.

Contribution

It presents a novel nonlinear observer for angular velocity estimation from single vector measurements, avoiding reliance on attitude or gyroscope data, and provides convergence analysis.

Findings

Convergence of the observer is proven using a detailed analysis.

The method works without attitude information or rate gyros.

Simulation results validate the effectiveness of the proposed approach.

Abstract

The paper proposes a technique to estimate the angular velocity of a rigid body from single vector measurements. Compared to the approaches presented in the literature, it does not use attitude information nor rate gyros as inputs. Instead, vector measurements are directly filtered through a nonlinear observer estimating the angular velocity. Convergence is established using a detailed analysis of a linear-time varying dynamics appearing in the estimation error equation. This equation stems from the classic Euler equations and measurement equations. As is proven, the case of free-rotation allows one to relax the persistence of excitation assumption. Simulation results are provided to illustrate the method.