基于非线性制导的四旋翼轨迹跟踪控制

四旋翼是一种欠驱动、强耦合的可垂直起降的飞行器，为了实现其能够以设定速度跟踪空间轨迹，设计了一种基于非线性制导算法的轨迹跟踪控制方法。该方法分为了导引与控制两部分组成，导引部分以任务轨迹与期望速度为输入量通过非线性制导算法输出当前四旋翼的期望加速度，控制部分以得到的期望加速度为输入量采用串级PID算法对四旋翼进行姿态控制，从而实现四旋翼保持设定速度对任务轨迹的跟踪。仿真结果表明，所提方法能够实现四旋翼对复杂任务轨迹的精确跟踪，二维复杂轨迹跟踪距离偏差不超过±0.6m，速度偏差不超过2m/s；三维复杂轨迹除了受自身控制力限制的飞行段外，跟踪距离偏差基本控制在±4m以内，速度偏差不超过2m/s。

Trajectory tracking control of quadrotor based on nonlinear guidance

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.