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Autonomous landing of a quadrotor on an UGV

This paper provides a complete solution for landing a quadrotor Unmanned Aerial Vehicle (UAV) on an Unmanned Ground Vehicle (UGV) in the outdoor environment. An image-based visual servo control law and a GPS-based navigation method are proposed, and the former method acquires the visual feedback from the camera attached to the quadrotor, while the latter strategy is used when the visual feedback is absent. For achieving more precise and stable performance in visually guided landing process, we design a specific landing marker that can provide different features as the distance between the quadrotor and landing target changes. Meanwhile, the corresponding detection and recognition algorithms are raised. Finally, a simulation experiment is carried out to validate the proposed vision algorithms and control strategies.