Automatic landing of unmanned aerial vehicle using fuzzy control

In order to improve the precision of trajectory tracking and the security of landing, a longitudinal control system based on fuzzy control for automatic landing of UAV is presented in the paper. An optimization method based on PSO (Particle Swarm Optimization) algorithm is proposed to design the Integrated Landing Reference System, which guarantees the security margin and deflection margin. As traditional control structure only controls sink rate during flare phase, which can´t guarantee safe touchdown pitch angle under disturbances. A fuzzy logic scheme is employed to make a compromise between trajectory tracking and touchdown security. Then a fuzzy control method based on GA (Genetic Algorithm) using analytically optimal function without quantization is proposed to design fuzzy controllers. Simulation results prove that the designed automatic landing control system performs good robust property under wind disturbance, aerodynamics parameters perturbation and sensor measurement errors, besides it improve the precision of landing point.