GPS-Denied Relative Motion Estimation For Fixed-Wing UAV Using the Variational Pose Estimator

TL;DR

This paper presents a robust, GPS-denied relative pose estimation method for fixed-wing UAVs using onboard optical sensors and a variational approach, enabling reliable tracking and handoff in challenging environments.

Contribution

It introduces a novel variational pose estimator based on the Lagrange-d'Alembert principle, specifically designed for fixed-wing UAVs in GPS-denied scenarios, with proven stability and robustness.

Findings

Estimator remains stable under noisy measurements

Effective in initial pose and velocity uncertainties

Simulations confirm robustness and accuracy

Abstract

Relative pose estimation between fixed-wing unmanned aerial vehicles (UAVs) is treated using a stable and robust estimation scheme. The motivating application of this scheme is that of "handoff" of an object being tracked from one fixed-wing UAV to another in a team of UAVs, using onboard sensors in a GPS-denied environment. This estimation scheme uses optical measurements from cameras onboard a vehicle, to estimate both the relative pose and relative velocities of another vehicle or target object. It is obtained by applying the Lagrange-d'Alembert principle to a Lagrangian constructed from measurement residuals using only the optical measurements. This nonlinear pose estimation scheme is discretized for computer implementation using the discrete Lagrange-d'Alembert principle, with a discrete-time linear filter for obtaining relative velocity estimates from optical measurements. Computer simulations depict the stability and robustness of this estimator to noisy measurements and uncertainties in initial relative pose and velocities.