The Algorithm And Simulation Study Of Quad-rotor Control System

Quad-rotor can be done is a vertical take-off and landing of coaxial type saucer-shaped aircraft,with light weight,small size,simple structure,flexible,as well as the economic price,is widely applied to the monitoring,fixed wing aircraft cannot perform rescue mission,military reconnaissance and other fields,has wide military and civilian applications.The quad-rotor aircraft is a typical underactuated system,and it also has many variables,nonlinear,strong coupling and interference sensitive characteristics.Therefore,the design of the control system is the key to ensure the effective completion of the quad-rotors.Based on the control algorithm as the core,aiming at the problem of model uncertainty and external disturbance,on the basis of sliding mode control is not sensitive to system parameters and unknown disturbance to the characteristics of the sliding mode method is designed on the basis of the two new attitude controller of sliding mode reaching law;Based on the research attitude controller,a new double closed loop controller with trajectory tracking function is designed.The main contents are as follows:Firstly,introduced the four rotor aircraft flight principle,on the basis of theoretical analysis of the dynamic characteristics of aircraft,according to the law of Newton’s second law and the torque resume system,the mathematical model on the basis of the corresponding model is simplified.Secondly,an effective solution to improve robustness is proposed based on anti-jamming and anti-vibration of quad rotor Based on the traditional sliding mode method,an integral sliding surface is designed to eliminate the steady-state error of the system,and a new variable index approach law is proposed to design the attitude control system.The existence and stability of sliding mode in global scope are proved by theory.Finally,the simulation results show that the designed controller not only improves the fast convergence ability but also improves the stability of the system,weakens the chattering and has a better effect.Thirdly,the first order norm of state variable is introduced on the basis ofthe traditional non-singular sliding mode reaching law,and a new adaptive change approach is proposed,and then the attitude controller is redesigned.The simulation results show that the proposed controller can effectively improve the response speed and robustness of the quad rotor.Finally,a double closed-loop design method is adopted for the study of the attitude self-stabilization flight and spatial position trajectory tracking of the quad rotor.The outer ring position controller is designed with a new type of inversion method.The design process is clear,the structure is simple,and the controller is easy to handle the uncertainty in the system.Inner attitude control design of a new type(ADRC),is a good way to solve the problem of coupling nonlinear system,and to reconstruct the nonlinear state error feedback control,implements the system rapid global convergence.The simulation results show that the attitude Angle and space trajectory can track the desired signal quickly,steadily and without overshoot,and can realize the requirement of high precision of the vehicle attitude adjustment and tracking accuracy.