Autonomous Landing of Rotary Wing Unmanned Aerial Vehicles on Underway Ships in a Sea State

Unmanned Aerial Vehicles (UAVs) can be further optimized as tools on-board ships with the development of lacking infrastructure, like their recovery at sea. Current technologies focus on vision-based systems with little consideration for ship motion. A novel autonomous landing technique is tested experimentally, featuring acoustic positioning to allow for landings in a wider breadth of conditions and to reduce the reliance on specially designed landing targets. A potential fields path planner is used to adapt for ship motion and provide obstacle avoidance and natural biasing away from the heaving ship deck. A sea state predictor is used to compensate for harsher sea conditions and ship motion, allowing the UAV to look for appropriate landing windows in higher sea states. Autonomous landings are demonstrated in a lab setting for sea conditions up to, and including, sea state 5. The ship motions are defined using real sea trials data from the decommissioned HMCS Nipigon.