A Nonlinear Observer for Air-Velocity and Attitude Estimation Using Pitot and Barometric Measurements

TL;DR

This paper develops a nonlinear observer for UAVs that estimates air velocity and attitude using minimal sensors, enabling navigation without GPS by analyzing observability and designing a robust estimation algorithm.

Contribution

It introduces an observability analysis for UAV trajectory planning and a nonlinear observer on SO3R3R using Pitot, barometric, and magnetometer data with IMU inputs.

Findings

Observer converges under minimally excited trajectories

Simulation confirms robustness and accuracy

Conditions for uniform observability established

Abstract

This paper addresses the problem of estimating air velocity and full attitude for unmanned aerial vehicles (UAVs) in GNSS-denied environments using minimal onboard sensing-an interesting and practically relevant challenge for UAV navigation. The contribution of the paper is twofold: (i) an observability analysis establishing the conditions for uniform observability, which are useful for trajectory planning and motion control of the UAV; and (ii) the design of a nonlinear observer on SO3R3R that incorporates pitot-tube, barometric altitude, and magnetometer measurements as outputs, with IMU data used as inputs, within a unified framework. Simulation results are presented to confirm the convergence and robustness of the proposed design, including under minimally excited trajectories.