Research on UAV Precision Landing Technology Based on ADRC

The unmanned aerial vehicle system (UAV) with automatic recovery function has been widely used because of its intelligence and automation in which precise landing function is essential. This paper developed a series of solutions to improve the landing accuracy through the analysis of system mathematical model and aerodynamic characteristics. Firstly, the active disturbance rejection controller (ADRC) is introduced to solve the interference introduced by nonlinear changes of the power system, so as to improve the system control robustness and anti-interference ability. Then, a coupling operator is introduced to construct a new UAV control loop structure creatively, and the horizontal deviation of UAV landing is controlled within a certain threshold. Finally, the differential GNSS state observer was designed and the landing strategy was optimized to improve the confidence of landing accuracy. The simulation and experiment was carried out in order to verify the effectiveness of the control algorithm, by introducing a gust of wind in the process of simulation model to simulate the external disturbance. The results show that ADRC has better robustness and environment adaptability than PID controller, and the new control loop structure can improve the landing precision and has a high degree of confidence.