A Lyapunov-Based Switching Scheme for Selecting the Stable Closed-Loop Fixed Attitude-Error Quaternion During Flight

TL;DR

This paper introduces a Lyapunov-based switching control scheme for UAVs that optimally selects stable attitude-error quaternions, reducing control effort and power during high-speed yaw maneuvers.

Contribution

It proposes a novel switching controller using Lyapunov functions to select stable equilibrium quaternions, improving energy efficiency in UAV attitude control.

Findings

Reduces control effort by up to 49.75%.

Decreases rotational power consumption by up to 28.14%.

Successfully demonstrated on a 31-gram quadrotor during high-speed yaw maneuvers.

Abstract

We present a switching scheme, which uses both the attitude-error quaternion (AEQ) and the angular-velocity error, for controlling the rotational degrees of freedom of an uncrewed aerial vehicle (UAV) during flight. In this approach, the proposed controller continually selects the stable closed-loop (CL) equilibrium AEQ corresponding to the smallest cost between those computed with two energy-based Lyapunov functions. To analyze and enforce the stability of the CL switching dynamics, we use basic nonlinear theory. This research problem is relevant because the selection of the stable CL equilibrium AEQ directly determines the power and energy requirements of the controlled UAV during flight. To test and demonstrate the implementation, suitability, functionality, and performance of the proposed approach, we present experimental results obtained using a 31-gram quadrotor, which was controlled to execute high-speed yaw maneuvers in flight. These flight tests show that the proposed switching controller can respectively reduce the control effort and rotational power by as much as 49.75 % and 28.14 %, on average, compared to those corresponding to an often-used benchmark controller.