多旋翼无人机自主精准降落的控制系统研究

针对多旋翼无人机降落时采用位置控制方式存在位置振荡和速度超调现象的问题，本文采用速度控制的方式进行降落，构建了一个完整的精准降落闭环速度控制系统。首先建立无人机精准降落速度控制系统的总体框架；然后进行无人机降落时多个坐标系之间的转换；再设计外环速度的"比例-积分-微分"（Proportion-Integral-Derivative，PID）控制系统和模糊自适应速度PID控制系统；最后进行2种控制系统的性能测试和对比实验。结果表明，无人机在这2种控制系统下均能成功降落到地面靶标上，且模糊自适应速度PID控制系统降落精度更高，达到了0.13 m以内。因此多旋翼无人机采用模糊自适应速度PID控制系统可实现自主精准降落。

A Research on Control System of Multi-rotor UAV Self-precision Landing

In view of the problem of positional oscillation and speed overshoot in the position control mode of multi-rotor UAV landing, the speed control method is adopted to land and a complete closed-loop speed control system constructed for precise landing. Firstly, the overall framework of UAV precise landing speed control system is established; secondly, the coordinate system of UAV landing and the transformation between coordinate systems are constructed; then, the outer-loop speed PID(Proportion-Integral-Derivative) control system and the fuzzy adaptive speed PID control system are designed; and finally, the performance tests and comparative experiments of the two control systems are carried out. The results show that the UAV can successfully land on the ground target under these two control systems, and the fuzzy adaptive speed PID control system has a higher landing accuracy, which is less than 0.13 meters. It can be seen that the multi-rotor UAV has realized the autonomous precise landing by adopting the fuzzy adaptive speed PID control system.