Quadrotor Position And Attitude Control Based On Nested Saturation Method

Quadrotor aircraft is the focus of domestic and foreign research.Because of its low cost and simple structure,it has a wide range of application value.In the related research of the quadrotor,the control method of the q uadrotor is a basic and key part.With more and more related research,various control methods of quadrotor emerge in an endless stream,in order to solve various practical problems in quadrotor flight.In this paper,two kinds of nested saturation controllers are designed to solve the pose control problem of a quadrotor UAV system with limited actuators,and their simulation and exper imental verification are conducted.The results show that the designed controller can effectively stabilize the four-rotor UAV system.Specific contents include:This paper has used Newtonian mechanics analysis theory to establish a four-rotor mathematical model,including power unit model,control efficiency model,dynamics model and kinematics model,based on top-down layer by layer modeling method.Under this model,the input-output relationship of each part is clear,which lays a foundation for the esta blishment of simulation model and the construction of experimental program.Firstly,based on the linearized quadrotor model,a nested saturation control law was designed for pitch and roll channels,and the simulation test was carried out for the controller.The simulation results show that the nested saturation controller can partially stabilize the original nonlinear system,and has its own advantages and disadvantages compared with the traditional cascade PID controller.Secondly,on the basis of the above simulation test,the real experiment based on the bench quadrotor device was carried out,and the experimental results verified the control effect of the controller.The experimental results of different initial errors showed that the controller can stabilize the four-rotor system with small initial errors,but the control effect is poor with large initial errors.Finally,a nested saturation control law based on the nonlinear quadrotor model was designed to solve the problem of small selection range of initial conditions.The proposed method can globally stabilize the original nonlinear system under reasonable assumptions,that is,the proposed control law can stabilize and control the quadrotor UAV from a reasonable large Angle deviation.This paper also shows that the simulation test and bench device experiment were carried out to verify the effectiveness of the proposed method.