Research And Implementation Of High Precision Flight Control Algorithm For Quadrotor UAV

As the key technology in the field of four rotor unmanned aerial vehicles(UAV),flight control technology has always been a hot spot of research by experts and scholars at home and abroad.The control precision is always an important factor affecting the UAV technology development and progress,at the same time it also determines the performance of the completion of four rotor UAV flight tasks,but because of the four rotor system itself has a high requirement for real-time and power consumption,some advanced and high precision control method because of large amount of calculation,time-consuming and other reasons to achieve better in the UAV platform.Therefore,it is of great significance to study the high precision four rotor UAV control algorithm.In this thesis,from the point of view of the control method and the purpose of practical application,the high precision control problem of the four rotor UAV is studied.First of all,based on in-depth study of four rotor UAV flight control principle and kinematics relation,dynamic model is established;in addition,through the research and analysis of the traditional PID control algorithm has advantages in four rotor UAV applications and shortcomings that the traditional PID control algorithm has the advantages of strong adaptability,while the advantages of simple structure and easy so,but there are some defects in the parameter setting,dynamic performance,nonlinear problems in application.In view of the above shortcomings,taking into account the anti-interference ability of the four rotor system,nonlinear,time-varying characteristics,the fuzzy logic control is studied deeply,and found that the fuzzy controller has small amount of calculation and control characteristics of short response time and strong robustness,high fault tolerance and simple design,especially suitable for nonlinear and time variable,model of incomplete application system.This thesis presents the parameter fuzzy cascade PID(PF-CPID)control algorithm based on cascade PID control method,fuzzy logic reasoning is used to adaptively tune the PID parameters,so as to simplify the parameter tuning process at the same time,strengthen the control in the application of adaptive nonlinear.Through the MATLAB model simulation of the control algorithm,it is concluded that the PF-CPID control algorithm has many advantages,such as small overshoot,short adjustment time,fast response and longtime stability,and the performance is much better than the traditional control method.In order to further verify the performance level of the PF-CPID control algorithm in practical application,this thesis established the four rotor UAV flight test platform,and designed and implemented the hardware operation environment and software program of UAV flight control system respectively.Change the flight control effect and attitude curve by observing the PF-CPID algorithm of four rotor UAV,can draw the PF-CPID control algorithm in the control precision and dynamic performance and stability and other aspects have shown a better control effect,It meets the high precision requirements of the UAV control,and effectively avoids the problem of calculation and real time caused by the improvement of precision.In the control precision,PF-CPID algorithm has a great improvement compared with the traditional control method,and its maximum precision lifting ratio can reach 28.12%.