Nonlinear control of underactuated vehicles with uncertain position measurements and application to visual servoing

The paper concerns the stabilization of thrust-propelled underactuated vehicles in the context of sensor-based control. First, a class of nonlinear feedback laws that ensure semi-global stabilization despite possibly large uncertainties on the position measurements is proposed. Then, application to the visual servoing of a Vertical Take-Off and Landing (VTOL) drone with a video camera is considered. In particular, it is shown that semi-global stabilization can be achieved, based on homography meaurements, with little information on the environment. Simulation results show the effectiveness of the approach.