A nonlinear model predictive control based control method to quadrotor landing on moving platform

Abstract

To address the problems that the UAV (Unmanned Aerial Vehicle) is vulnerable to distance limitation and environmental interference when tracking and landing on a moving platform autonomously, the accuracy of position estimation relying only on visual odometry in the point‐featureless environment is insufficient, and the traditional linear path planning solvers and controllers cannot meet the fast and safe requirements under the non‐linear strong coupling characteristics of the cooperative landing system, an nonlinear model predictive control (NMPC)‐based multi‐sensor fusion method for autonomous landing of UAVs on motion platforms is proposed. The UAV combines the position information obtained by the RTK‐GPS and the image information obtained by the camera and uses the special identification codes placed in the landing area of the UAV to carry out cooperative planning and navigation while using UKF (Unscented Kalman Filter) to estimate the position of the moving platform and using the interference‐resistant NMPC algorithm to optimise the UAV tracking trajectory based on the precise positioning of the two platforms to achieve the autonomous landing control of the UAV. The simulation and practical experimental results show the feasibility and effectiveness of the proposed algorithm and the autonomous landing control method and provide an effective solution for the autonomous landing of quadrotors on arbitrarily moving platforms.

A Real-Time Localization Algorithm for Unmanned Aerial Vehicle Based on Continuous Images Processing

“…If there are m matching points, let the nth matching point be q n . To calculate the ground coordinates x q3 , y q3 , z q3 of one of the matching points q 3 , the solution form is shown in formula (2).…”

“…Unlike pilot-navigated UAVs, autonomous control systems heavily rely on accurate feedback of the vehicle's position. Current common technologies for UAV localization include Global Positioning System (GPS) [1,2], laser radar [3,4], ultrasound [5], Ultra-Wideband (UWB) [6], radio frequency [7,8], and visual methods [9,10]. While GPS is commonly employed for obtaining location information in open areas, its performance degrades when there is interference with GPS signals.…”