Vision-based collaborative lifting using quadrotor UAVs

This paper presents vision-based lifting of a payload using two quadrotor UAVs. It is assumed that the exact position of a payload is not available. Specifically, for multiple UAVs to approach and connect the correct spots on the payload, image-based visual servo (IBVS) is adopted. A sliding mode controller is designed to track reference positions and velocities generated by IBVS. A scenario is designed from taking off to lifting the payload. The proposed methods and settings are validated with an experiment.