Abstract:The quadrotor is an under-driven,strong-coupling aircraft that can take off and land vertically. In order to realize its ability to track a space trajectory at a set speed,a trajectory tracking control method based on nonlinear guidance algorithm is designed.The method is divided into two parts: guidance and control.The guidance part takes the mission trajectory and the desired speed as input and outputs the expected acceleration of the current quadrotor through nonlinear guidance algorithm.The control part uses the cascade PID to control the quadrotor's attitude based on the expected acceleration obtained,so that the quadrotor can maintain the set speed to track the mission trajectory.Simulation results show that the proposed method can accurately track the complex task trajectory of the quadrotor.The tracking distance deviation of two-dimensional complex trajectories is less than ±0.6m, and the speed deviation does not exceed 2m/s. In addition to the flight segment limited by its own control force, the tracking distance of three-dimensional complex trajectories basically remains within ±4m, and the speed deviation does not exceed 2m/s.