Design Of Control System For Quadrotor Based On Auto-disturbance Rejection

The rapid development of science and technology has changed human society.The air delivery of express delivery,the popularity of aerial photography,drone driving,etc.gradually infiltrate people's daily lives.The kites that were placed during childhood holidays gradually disappeared and replaced by remote sensing aircraft.Because of its good maneuverability,adaptability,simple structure and low cost,the aircraft is widely used in military warfare and civilian life.The rapid development of micro-motor technology,energy storage technology and control technology,and the growing market of civil aircraft have set off a research boom at home and abroad.In this paper,the control system of the quadrotor is studied.The cascade PD attitude control system of the quadrotor,the active disturbance rejection attitude control system,the improved active disturbance attitude control system and the PD position control system are designed.In this paper,the development history,body structure,flight principle and control system of the quadrotor are briefly introduced.Combined with classical mechanics,aerodynamics and other related knowledge,a dynamic model is established for the quadrotor based on Newton's Euler equation.At the same time,considering that the quadrotor is vulnerable to turbulent wind field when flying in the air,the turbulent wind field model is established according to the description of the turbulent wind field by the Dryden model.The forces acting on the quadrotor in turbulent wind field are analyzed.In MATLAB/Simulink,the dynamics model and turbulent wind field of the quadrotor are built.Then,according to the characteristics of the system,such as non-linearity,strong coupling,under-actuation,uncertainty of model parameters and internal parameters,and susceptibility to external disturbances,an aircraft attitude control system based on cascade PD control is designed.The control performance of cascade PD and the control performance under turbulent wind field are analyzed based on the simulation results in simulink.Then,according to the advantages and disadvantages of cascade PD control performance,the active disturbance rejection controller(ADRC)is introduced,and the principle of auto-disturbance controller and the physical meaning of controller parameters are introduced.At the same time,the control system structure of the quadrotor is analyzed,and the discrete active disturbance rejection controller attitude control system of the aircraft is designed.and the discrete active disturbance rejection controller attitude control systemfor aircraft is designed.Simulate in simulink and compare and analyze with the cascade PD control system to verify the advantages of the auto disturbance rejection controller: faster adjustment time;no overshoot of the control system;and self-interference in the turbulent wind field The controller can achieve better wind resistance.Finally,in order to improve the tracking performance of the state quantity of the controller and the anti-interference ability of the controller,and obtain better control performance,the active disturbance rejection controller is improved.Firstly,the characteristics of the fal function are analyzed for the active disturbance rejection controller,and then the fal function in the anti-interference control is improved to obtain a better newfal function.The active disturbance rejection controller is designed by the newfal function,and the stability of the extended state observer is analyzed.The improved control system of the aircraft was simulated by a modified auto disturbance rejection controller,and the position control of the quadrotor was designed.The simulation results show that the state-following effect of the improved active disturbance rejection controller is better than that of the original anti-interference tracking,and the adjustment time is shorter.When the large interference is encountered,the estimation of the interference is more accurate.The anti-interference ability is stronger.