Adaptive filtering and image based visual servo control of a ducted fan flying robot

This paper considers the question of fully image based visual servo control for a Vertical Takeoff and landing (VTOL) Unmanned Aerial Vehicle. The visual targets considered are coloured blobs on a flat surface to which the normal direction is known. A fully non-linear adaptive control design coupled with an asymptotic filter is provided that ensures the stability of the closed-loop system in a large domain. The image features used are a first order spherical moment for position and an estimation of the optic flow measurement for velocity. Experimental results are presented showing the stabilization of the VTOL UAV HoverEye in front of a colored target.