农用多旋翼飞行器串级分数阶PID控制

Cascade fractional order PID control of farm unmanned aerial vehicle

为提高农用无人机动态性能,基于传统串级整数阶PID控制算法,提出一种串级分数阶PID控制算法。以四旋翼无人机为研究对象建模,并利用遗传算法对串级整数阶PID和串级分数阶PID参数进行整定,得到最优控制后采用MATLAB/SimuLink仿真分析,证明串级分数阶PID控制效果优于串级整数阶PID。以四旋翼无人机实物为对象进行试验,测试结果表明,串级分数阶PID比串级整数阶PID的调节时间缩短了0.24 s,总体性能更优,表明仿真结论可靠。研究结果表明,串级分数阶PID控制算法可用于农用无人机的飞行控制。

The advantages of fractional order PID algorithm compared with traditional integer order PID control algorithm were analyzed to improve the dynamic performance of farm unmanned aerial vehicle(UAV).The fractional order PID algorithm has higher control accuracy.A cascade fractional order PID control algorithm with higher update frequency is proposed based on traditional cascade integer order PID control algorithm and comprehensive implementation difficulty.It uses fractional order PID control algorithm in inner loop and integer order PID control algorithm in outer loop.The four-rotor UAV was modeled,and the parameters of the two algorithms were tuned by genetic algorithm.After obtaining the optimal control,MATLAB/SimuLink was used to simulate and analyze.The results of simulation showed that the overshoot of the two algorithms was close to zero.The regulation time of cascade fractional order PID control algorithm and cascade integer order PID control algorithm was 0.263 s and 0.386 s,respectively.The former is 31.9%less than the latter.It is indicated that effect of the cascade fractional order PID control algorithm is better than that of the cascade integer order PID control algorithm.In order to further compare the two control algorithms,a four rotor UAV is built and tested on a multi degree of freedom test bench which can test the attitude changes of multi axis aircraft.The results showed that the settling time of the cascade fractional-order PID controller was 0.24 s shorter than that of traditional algorithm.The results of simulation and experimental showed that quality of the cascade fractional order PID control algorithm was better than that of the cascade integer order PID control algorithm.The regulation time is short and the regulation process is more stable.The results of comprehensive analyses showed that the cascade fractional order PID control algorithm can further improve the operational sensitivity,optimize the flight control performance,and improve the operation efficiency of multi rotor UAV in agricultural production when applied to agriculture.It can help reduce flight accidents as well.