Autonomous recovery of a Fixed-wing UAV Using a Line Suspended Between Two Multirotor UAVs

Abstract

This article presents an autonomous recovery system for fixed wing UAVs which is using a line suspended between two multirotor UAVs to catch a line with a hook hanging from a fixedwing UAV. This method of recovery is particularly suitable for recovery in space constrained areas such as on small ships. A control system is presented for the proposed recovery concept and the concept is validated through experiments. The results include 17 test runs to characterize control accuracy, followed by 3 successful recoveries. With the selected equipment and tuning values, the multirotors were able to track the fixed-wing UAV with a mean error of 0.8 m at the moment the catch would have happened in the 17 test runs. The margins for missing for the three recoveries were 1.0-2.1 m showing that this recovery method is robust.