Autonomous UAV controlled collision landing via eye-in-hand visual servoing

Abstract

Catastrophic damage to fixed-wing unmanned aerial vehicles (UAV) is most likely to occur during the landing stage. Vision-based autonomous landing methods for small UAV have been proposed in literature to address the issue. This paper improves on previous work on vision-based landing via a controlled collision with a large inflatable airbag. In the proposed method the UAV steers towards a large, multi-coloured, dome-shaped airbag using visual feedback obtained from a UAV-mounted camera. A multi-colour airbag is proposed to facilitate a robust and efficient colour-based detection method for real-time detection of the dome in images. A proposed visual servoing controller translates the dome location into desired pitch and yaw rate commands to achieve an exponential decay of the image error. A model predictive UAV controller that achieves desired roll and yaw rates is designed and tested in simulations. The lateral and longitudinal UAV dynamics were decoupled and a linear discrete state space model of the dynamics was obtained via system identification. The proposed dome landing method has been implemented on the FlightGear flight simulator and has presented successful landings in simulations over multiple trials.