A global observer for attitude and gyro biases from vector measurements

TL;DR

This paper introduces a simple nonlinear observer for estimating a rigid body's attitude and gyro biases using vector measurements and rate gyros, with proven global and local convergence properties.

Contribution

It presents a novel geometry-free nonlinear observer with guaranteed convergence, simplifying stability analysis compared to existing methods.

Findings

Observer achieves uniform global asymptotic convergence.

Local exponential convergence is demonstrated.

Numerical simulations confirm excellent performance.

Abstract

We consider the classical problem of estimating the attitude and gyro biases of a rigid body from vector measurements and a triaxial rate gyro. We propose a simple "geometry-free" nonlinear observer with guaranteed uniform global asymptotic convergence and local exponential convergence; the stability analysis, which relies on a strict Lyapunov function, is rather simple. The excellent behavior of the observer is illustrated through a detailed numerical simulation.