Attitude Control Methods Design Of Quadrotor Vehicles

Quadrotor uav has the characteristics of multi-input and multi-output variable coupling,underdrive and external disturbance,and is a kind of platform suitable for the research of control algorithm.In this paper,considering variable coupling,external disturbance and actuator input con-straints,different attitude control algorithms are improved and designed,and their performance is verified.Firstly,the flight principle of the quadrotor uav is described,and its force is analyzed.A nonlinear dynamics model with six degrees of freedom of the quadrotor as the state quantity is established,and the coupling of variables is further analyzed to provide a research basis for the subsequent controller design.Then a cascade PID controller for quadrotor attitude is designed for model-free scenarios to improve the anti-disturbance performance of the system.In view of the traditional PID parameters can not be adjusted in real time,a gain scheduling PID controller based on fuzzy theory is designed.The proportional,integral and differential gain parameters of the controller can be adjusted online to improve the adaptive ability of the system.The performance of the algorithm without considering the variable coupling is verified in the simulation environment.Then,a model-based predictive controller which can effectively deal with coupling and constraints is proposed for the application scenarios where precise models are known.Firstly,the equilibrium linear model is used as the prediction model,and the speed constraint of the motor is considered.The simulation results show that predictive control can solve the problem of variable coupling and constraint of quadrotor well.Furthermore,the takagi-Sugeno fuzzy model is adopted as the prediction model,considering that the controller designed by the equilibrium linear model as the predic-tion model can not operate well in a wide range of attitude angles of the quadrotor.In order to solve the problem of poor anti-disturbance perfor-mance of predictive control,a disturbance observer compensation control law is adopted.The simulation results show that the proposed controller can keep a good tracking effect when the attitude Angle changes dynamically in a large range and has a certain anti-disturbance performance.Finally,a quadrotor experimental platform was built,and the com-pilation environment and code were optimized to verify the reliability of the proposed algorithm.Experimental results show that the controller de-signed in this paper has good performance in the variable coupling system of quadrotor.There are 71 figures,8 tables,and 81 citations in this thesis.