| Global satellite positioning technology is widely used in the positioning system of quadrotors.In some special working conditions,GPS signals are easily affected by adverse factors such as interference,shielding,shielding,etc.,leading to GPS loss or signal instability,resulting in reduced accuracy and even failure of quadrotor position navigation.The visual-aided positioning method has the advantages of simple structure,wide application range and stable operation,which can effectively make up for the defects of GPS navigation.Therefore,the research on autonomous landing system of quadrotor based on vision has certain theoretical and practical significance.Aiming at the problem of disturbance of attitude and unstable GPS navigation signal during quadrotor landing,this paper studies the Active Disturbance Rejection Control(ADRC)during visual-aided autonomous landing of quadrotor aircraft.The active disturbance rejection control is optimized by using the descending LESO optimization scheme,and the simulation is compared with PID control in MATLAB.The infrared beacon is optimized so that the aircraft can obtain effective horizontal target position information and improve the locking effect of the vision system.The visual static beacon tracking algorithm is studied,and the inverted cone control landing logic is used to keep the horizontal distance error of the aircraft relative to the target position within the threshold range,which improves the anti-jamming ability and autonomous landing ability of the system.The hardware and experiment of visual-aided quadrotor autonomous landing system are studied.In order to get better experimental data,a physical verification platform based on visual feedback was built for actual flight verification.Experimental results show that the optimized ADRC algorithm has stronger anti-jamming ability and is more stable.Infrared beacon has a wider range of use and a higher target recognition rate,which can meet the requirements of visual assisted landing of micro-quadrotor aircraft. |
