An integrated localization-navigation scheme for distance-based docking of UAVs

TL;DR

This paper presents an integrated estimation-control approach enabling UAVs to localize and dock at an unknown landmark using a single sensor, validated through theoretical proofs and real quadcopter experiments.

Contribution

It introduces a novel combined estimation and control scheme for UAV docking using only a single landmark in GPS-denied environments.

Findings

Successful convergence of the estimation and docking in simulations

Validation on quadcopters with UWB and optical sensors

Theoretical proof of convergence using LaSalle's invariance principle

Abstract

In this paper we study the distance-based docking problem of unmanned aerial vehicles (UAVs) by using a single landmark placed at an arbitrarily unknown position. To solve the problem, we propose an integrated estimation-control scheme to simultaneously achieve the relative localization and navigation tasks for discrete-time integrators under bounded velocity: a nonlinear adaptive estimation scheme to estimate the relative position to the landmark, and a delicate control scheme to ensure both the convergence of the estimation and the asymptotic docking at the given landmark. A rigorous proof of convergence is provided by invoking the discrete-time LaSalle's invariance principle, and we also validate our theoretical findings on quadcopters equipped with ultra-wideband ranging sensors and optical flow sensors in a GPS-less environment.