An integrated localization-navigation scheme for distance-based docking of UAVs
This work addresses the practical problem of autonomous UAV docking without GPS, which is important for applications like aerial refueling or landing on moving platforms.
The paper tackles distance-based docking of UAVs using a single landmark at an unknown position. It proposes an integrated estimation-control scheme that achieves relative localization and navigation, validated on quadcopters with UWB and optical flow sensors in GPS-less environments.
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.