The Four Rotor Attitude Control Based On PID Algorithm

The Four-rotor UAV is a complex controlled object with a stable, non-linear, strong coupling characteristics, its flight control methods involve Mechanics principle, sensor theory of communication technology, computer technology and other disciplines. Thesis focuses on the analysis of the sensor debug, the establishment of dynamic model and simulation,the establishment of WIFI data channel and the design of the attitude of the control system based on PID algorithm.It is declared that through the study of four rotor aircraft structure characteristics, the attitude calculation method and flight control theory, then design the main control system based on S3C2440 chip as the platform of hardware, software development in Linux environment. The hardware platform integrates MPU-6000 and KS103 for the inertial measurement unit of the flight attitude control system. The design of software to Linux file system as the operation platform, then build the cross compile environment and write application layer and control layer on PC platform. In the data channel, using RS232 and IIC protocol to realize data analysis from the sensor and establish a data channel between the host computer and the target board based on the socket TCP communication protocol. Through the method of weighted fusion to deal with the measurement data from gyroscope and the current sensor, to estimate the current motion trends. Then make the attitude angle and stability of attitude Angle difference, treat the difference as a fuzzy PID controller input, through the calculation of PID control algorithm, obtain rapid convergence to the target angle corresponding to the anterior horn motor to adjust volume, so as to change the rotor speed to make aircraft to steady attitude adjustment.It is stated that this paper focus on the design of four rotor aircraft autonomous flight control system and build the software and hardware platform, then put emphasis on the debugging of the sensor and the design of the algorithm. Respectively introduced the pitching Angle proportion, integral and differential three kinds of convergence algorithm, and then design the incremental PID algorithm of software. Paper in the final build four rotor pitch axis attitude for the modeling and simulation. In the end test results show that the research about the PID algorithm in the control of four rotor attitude angle is feasible, to ensure the four rotor in the take-off state is stability under the influence of the airflow disturbances.