The Design Of Quadcopter Control System And Research Of Its Attitude Algorithm&contrl

Quadcopter is a kind of excellent and novel vertical liftable multi-rotor aircraft, which is taking a more and more important position in military and civilian field of unmanned vehicle. Various aspects of research works about the quadcopter are comprehensively and deeply carried out recent years. In this paper, we studied the fundamentals, systematic design, attitude algorithm and control ways of the quadcopter.First, we introduced the current situation and development prospects of the quadcopter. Also, we studied the quadcopter basic principles, Euler angles and quaternions attitude expressions, mathematical model and it’s identification methods. According to quadcopter system’s functions, we designed the system hardware circuit schematics and PCB. Then we completed welding, installation and commissioning work to build the hardware platform of quadcopter.Then, in MDK development environment, we successfully transplanted the uCOS-III operating system to STM32 microcontroller chip, and designed sub-tasks of total system. Among the sub-tasks, we detailly designed the NRF24L01 module and the serial port communication tasks. In this way, we developed a stable platform for software debug. On this basis, we detailly analysed the MPU6050 gyroscope and accelerometer noise signal. In aid of MATLAB, we designed an IIR low-pass filter to filtered out the noise of motor vibration. By comparing the complementary filter, Kalman filter, and quaternion, we decided to use MPU6050 internal DMP solution method as the main method to solve the attitude of our quadcopter.Finally, we tested the system identification method of least squares on our quadcopter, and successfully identified the actual mathematical model of attitude control system. On basis of the mathematical model, we designed a PID controller to control the attitude. Through theoretical analysis and practical experiments, we studied the stability of the system, and the control effect. Eventually, we get a good attitude control effect. Moreover, we reviewed and summarized the research deficiencies and shortcomings of this article, then made a plan and prospects for further research.