Control System Design And Implementation Of A Mini Quadrotor UAV

The small four-rotor UAV is light-weight,small size,stability and easy to operate.By controlling the speed of four motors,six degrees of freedom can be achieved,such as the change of height,forward and backward movement,left and right movements.Since the beginning of the 21st century,with the development of microelectronics technology and satellite navigation,the UAV have been widely used in national defense,land survey,community inspection,film and television filming.The application of UAV infiltrates all aspects of society,The research on UAV is very important.The Small quadrotor UAV is easy to be interfered by external environment factors,especially in windy environment,in addition,the small quadrotor UAV has many other problems,such as poor attitude calculation ability,short endurance time and so on.In view of the above problems,this paper designs a four rotor UAV using STM3 2 series chip as microprocessor.The rack style is similar to the English letter "X".the application of fuzzy PID(Proportion Integration Differentiation)algorithm based on PID algorithm in attitude control.The following work arrangements are as follows:(1)Through consulting the literature,understand the flight principle of UAV.According to the principle of dynamics,the mathematical model is established.The quadrotor UAV can fly in six kinds of attitude.Because of the different lift of the four rotors,the flight attitude of the UAV changes,so the body coordinate system can be established;when the position of the UAV changes,the ground coordinate system can be established accordingly.(2)After the establishment of the mathematical model,complete the selection of hardware.The hardware platform of this paper adopts modular design.It is convenient for later development,mainly including microprocessor,attitude sensor,satellite positioning module,remote control module and power module.(3)The realization process of flight control system is deduced by quaternion algorithm.By creating the mathematical model of the attitude sensor and the quaternion is fused with each sensor to calculate the attitude of Euler angle.Considering the precise control of attitude angle,in order to make up for the defects of traditional PID controller,this paper creates a fuzzy PID control scheme.In order to verify the control effect of the two algorithms,Verify whether the fuzzy PID control algorithm has better control effect.(4)Through the outdoor flight test to verify the effectiveness of the four rotor UAV control system,through the UAV outdoor take-off and landing,hover,autonomous flight,endurance and other tests,it is proved that the design of four rotor UAV meets the requirements of the project.