Global Finite-Time Attitude Tracking via Quaternion Feedback

TL;DR

This paper develops global finite-time attitude controllers for rigid bodies using quaternion feedback, overcoming topological constraints with hybrid control and nonsmooth feedback, applicable in various measurement scenarios.

Contribution

It introduces novel hybrid control techniques and a finite-time bias observer for quaternion-based attitude tracking, ensuring bounded control torques and broad applicability.

Findings

Achieves finite-time stability in attitude tracking.

Provides bounded control torques in all scenarios.

Includes existing controllers as special cases.

Abstract

This paper addresses the attitude tracking of a rigid body using a quaternion description. Global finite-time attitude controllers are designed with three types of measurements, namely, full states, attitude plus constant-biased angular velocity, and attitude only. In all three scenarios hybrid control techniques are utilized to overcome the well-known topological constraint on the attitude manifold, while coupled nonsmooth feedback inputs are designed via homogeneous theory to achieve finite-time stability. Specially, a finite-time bias observer is derived in the second scenario and a quaternion filter is constructed to provide damping in the absence of velocity feedback. The proposed methods ensure bounded control torques a priori and, in particular, include several existing attitude controllers as special cases.