Robust autonomous landing control of quadrotor based on optical flow
ZHANG Lian-hua
WANG Jing
SHI Zong-ying
ZHONG Yi-sheng
Abstract：For autonomous landing of a small quadrotor, an attitude estimation method is proposed using optical flow, and a robust controller based on signal compensation is designed. Firstly, the ratio of velocity to depth is acquired by singular value decomposition (SVD) from the general optical flow motion model, and the altitude data are obtained by integrating the ratio of vertical speed and altitude. Then, the nonlinear model of the altitude channel is divided into a nominal linear model and an equivalent disturbance considering the influences of the ground effect and other uncertainties. And a robust controller based on signal compensation is designed, which consists of a nominal controller and a robust compensator. The nominal controller is designed for the nominal system to get the desired tracking performance, and the robust compensator is applied to restrain the influence of the equivalent disturbance. Finally, it is proved that the tracking error for the altitude channel can converge to a given neighborhood of the origin in finite time by the robust controller. Landing experimental results for a small quadrotor demonstrate the effectiveness of the proposed altitude estimation method based on optical flow and the robust controller.
Keywords：unmanned aerial vehicleoptical flowrobust controlautomous landing
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 1492-1500 )