A method of surface estimator of automatic landing for high-aspect-ratio UAV with single side armed

For the wheeled and single-side armed UAV with high aspect ratio, the single-side wingtip will contact the ground if the lateral control command exceeds the predetermined roll command limiter for flaring, which brings the UAV into a dangerous situation. This paper proposed a new lateral control method with surface estimator to land the UAV automatically and safely. Through analyzing the control structure and the influence of single-side armed bomb, a surface estimator is provided to estimate the steady surface deflects at the end of sliding and compensated to the actuator control loop when flaring. Finally, simulation results show that the estimator is valid and the results are correct.