Research On The Flight Control System Of Quadrotor Unmanned Aerial Vehicles

With the rapid development of automation,informatization and unmanned technology,drones are widely favored,and their use has gradually expanded to various industrial fields and people’s daily activities.At present,the most commonly used quadrotor UAV,which is not only capable of vertical take-off and landing and stable hovering,but also has the characteristics of small flight loss,low manufacturing cost,strong maneuverability and not easy to be found.When UAVs perform tasks outdoors,due to unknown factors such as weather,there are often highly uncertain wind disturbances in their flight areas.Therefore,in this case,the flight safety of UAVs and whether they can be successfully completed are under review.The tasks performed have a huge impact.Coupled with the small size of the quadrotor UAV,the flight inertia is reduced,which makes it more sensitive to wind interference.The task is a big challenge for researchers.Therefore,this thesis conducts in-depth research on the flight control of quadrotor UAV under wind interference.The main research contents of this thesis are as follows:(1)The flying principle of the quadrotor UAV is introduced,and the coordinate system of the quadrotor UAV is established.Then,the nonlinear dynamic equation of the quadrotor UAV is established according to the position translation motion and attitude rotation motion of the quadrotor UAV.Then,the composition of natural wind and the influence of wind disturbance on the flight of the quadrotor UAV are analyzed,and the nonlinear dynamic equation of the quadrotor UAV under wind disturbance is obtained.Finally,the cascade flight control of the quadrotor UAV under wind disturbance is established.system.(2)Aiming at the problem that the traditional quad-rotor UAV cascade PD controller cannot meet the requirements of rapid response and stable control under strong wind interference,a quad-rotor UAV flight control method based on model predictive position control is proposed,and simulated and verify the effectiveness of the model predictive position controller.The simulation results show that the designed quad-rotor UAV model predictive position controller can improve the position of the quadrotor UAV under wind interference control dynamic performance and steady-state anti-interference.(3)Aiming at the problem of poor steady-state accuracy and low robustness of the quadrotor UAV under wind interference,the traditional PD attitude controller has a high-order sliding mode attitude control algorithm for the quad-rotor UAV under wind interference.The simulation results show that the designed high-order sliding mode attitude controller can realize the stable control of the four-rotor UAV under wind interference,and improve the steady-state accuracy and robustness of its attitude control.(4)Aiming at the complicated design of high-order sliding mode attitude control algorithm,a four-rotor UAV flight control method under wind interference based on nonsingular terminal sliding mode attitude control is proposed.The high-order sliding mode attitude control is simplified.The simulation results show that the designed non-singular terminal sliding mode attitude controller can realize the finite-time stable control of the fourrotor UAV under wind interference,and can achieve the same accuracy and robustness as the high-order sliding mode attitude control.