Design Of Control System And Research On Control Algorithm Of Four Rotor Aircraft

Four-rotor aircraft has entered the field of vision since the beginning of the 20 th century.However,due to the fact that the technical level was not mature enough and the equipment and equipment were not yet efficient and convenient,there was no major breakthrough in the research related to the quadrotor.Until entering the 21 st century,with the continuous improvement of micro-electric technology,control theory and methods,high-tech equipment,and quad-rotor aircraft with small size,light weight and high sensitivity,it has been favored by many domestic and foreign researchers and aircraft enthusiasts.They have carried out relevant research work on them and achieved many research findings in the academic and industrial fields.They have also been used in civil,military,and commercial fields,and have demonstrated their practical value.Because the quadrotor has four input variables and six output variables,it is a typical nonlinear and underactuated complex system.It requires the use of efficient filtering algorithms and control algorithms to achieve the control of the aircraft's flight attitude while reducing the external environment and the influence of disturbance factors on the flight attitude of the aircraft.In order to deeply study the control system of the quadrotor,the research needs to be done from several aspects such as the working principle,basic structure,dynamic model,attitude filtering and attitude control of the aircraft.This article takes the quadrotor aircraft as the research object,and starts from software and hardware design,sensor data collection,data filtering and attitude solving,and control algorithm design.The specific research contents are as follows:(1)Combining the hardware model structure and flight operation mode of the quadrotor,the four-rotor aircraft experimental model was constructed from two aspects of hardware selection and software program.Firstly,the MPU6050 sensor,HMC5883 L electronic compass and ATmega328 P MCU are used to construct the physical aircraft platform.Then the flight control program is designed from the aspects of initial setup module,sensor data acquisition module,data filter module,attitude fusion solver module and attitude control module.Finally,subsequent attitude fusion and attitude control related research experiments.(2)For the four-rotor aircraft inertial measurement unit measurement value filtering and attitude information solving problems,three filtering algorithms are used to filter the measurement values of the inertial measurement unit,and Euler angles are used to represent the attitude calculation results,and the three filtering methods are compared.The experimental results of the algorithm show that the second-order complementary filter algorithm has good filtering performance,which not only reduces the measurement error,but also increases the accuracy of attitude calculation.(3)By studying the structure and working principle of the quadrotor aircraft,using the Newton-Euler equation to derive its dynamic model,and selecting a single closed-loop PID and double closed-loop PID control algorithm to design the corresponding control function module,the experimental verification PID algorithm can be completed Attitude control of the aircraft.(4)Since the PID algorithm implemented in this paper does not consider its anti-jamming capability,the PD control algorithm,sliding mode control algorithm and back-stepping control algorithm are studied separately,and three kinds of control are designed on the MATLAB/Simulink platform according to the mathematical model of the corresponding algorithm functional module.In the algorithm simulation process,wind disturbance factors are added to simulate real-world disturbances to test the performance of each algorithm against disturbances.The results show that the sliding mode control algorithm is more robust and can achieve accurate and high-speed and effective attitude control.