Research On UAV Flight Stability Control

In recent years,four-rotor UAV in the field of consumption,especially in the field of aerial success,so that the four-rotor unmanned aircraft into the public view,in addition to the four rotor UAV in the industrial field has gradually more and more applications.The four-rotor UAV has a six-direction movement in the air,respectively: vertical movement,front and back movement,left and right movement,pitching movement,roll motion,yaw movement,but control four-wing UAV input quantity is only four,that is,by controlling the speed of four motor to change its posture,so it is due to drive system.Because of the non-linear relationship between the lift generated by the rotation of the propeller and the propeller speed,it is also a nonlinear system,which includes the processing of various sensor data,the solution of the attitude,and the optimization of the control algorithm.In addition,the four rotor UAV is disturbed by wind during flight,which leads to the complicated control of the flight stability of the four-rotor UAV.This paper uses STM32F407VET6 chip as the main controller of the four-rotor UAV,using the six-axis motion sensor MPU6050,with the three-axis magnetometer sensor AK8975 constitute the nine-axis motion module,through the gyroscope,accelerometer,and magnetometer sensor are more comprehensive to collect four rotor UAV attitude related data.Due to the cumulative error of the gyroscope for a long time,the angular velocity error of the gyroscope is corrected by the complementary filter combined with the accelerometer and the magnetometer,and the attitude of the four-rotor UAV is calculated by the method of four-number.On the basis of the angle single loop PID control,the double loop PID control is used to control the angular velocity of the UAV,which improves the stability of the four-rotor UAV.