Robohub has an ongoing effort to make the latest papers in robotics accessible to the general audience. Striking once again on that subject, they have shown us a video of an unmanned Areal Vehicle (UAV) communicating via decentralized control for safe landing on a moving unmanned Ground Vehicle (UGV).
Small Unmanned Aerial Vehicles can be both safe and manoeuvrable, but their small size means they can’t carry much payload and their battery life will only allow for short flights. To increase the range of a small UAV, one idea is to pair it with an unmanned ground vehicle that can carry it to a site of operation and transport heavier cargo. Having both ground and aerial perspectives can also be useful during a mission.
One challenge is to make sure the vehicles have the ability to rendezvous and perform coordinated landings autonomously. To this end, a paper by Daly et al. in Autonomous Robots presents a coordinated control method and experimental results for landing a quad-rotor on a ground rover.
The two robots communicate their positions, converge to a common docking location and the dock successfully, both indoors and out.
In the video above the use of a coordinated control strategy for autonomous docking of a Aeryon Scout UAV onto a skid-steer UGV from Clearpath Robotics is demonstrated. The controller handles the non-linearities inherent in the motions of the two vehicles, and is stable in the face of multi-second time delays, allowing unreliable Wi-Fi communication to be used in the landing. Both indoor and outdoor experiments demonstrate the validity of the approach, and also reveal the major disturbance caused by the ground effect when hovering over the ground vehicle.