Optimization and Tracking Control for UAV Spot Landing Trajectory on Sloped Runway

Aiming at the issues of touchdown overshoot or low-altitude floating caused by mismatches in the landing trajectory angle or sink rate during UAV spot landing on sloped runways, which may affect landing accuracy and safety, this paper proposes a landing trajectory optimization and tracking control strategy adapted to sloped terrain. First, a segmented optimization method for spot landing trajectory adapted to sloped runway terrain is proposed based on the Gauss Pseudospectral Method (GPM). Then, a position and attitude decoupled flight control method for spot landing on a sloped runway is proposed based on the direct lift control concept. Additionally, controllers are designed using Dynamic Surface Control (DSC) technology, along with Extended State Observer (ESO) to estimate system states and disturbances during the landing process. Simulation results validate the feasibility and effectiveness of the proposed landing strategy.