Research On Ducted UAV Flight Control System Based On Active Disturbance Rejection Control

The ducted UAV is a UAV that uses a duct to surround the rotor.Compared with the traditional rotor UAV,it adopts a duct that surrounds the rotor similar to a turbofan engine of a jet aircraft,which can provide higher Lift and thrust,while having greater efficiency and lower noise levels.Ducted UAVs are widely used in military,civilian and commercial fields,such as reconnaissance,monitoring,logistics,firefighting and search and rescue.The flight dynamics of ducted UAVs are complex,involving a large number of variables and strong coupling between channels,as well as nonlinearity and instability.Changes in the external environment will lead to increased uncertainty of the system response,and the coupling relationship between the manipulation channels will also have a great impact on its stability.Therefore,this paper aims to study the flight control system of ducted UAVs to improve their adaptability and stability,and lay the foundation for their application in various fields.Firstly,the kinematics equation and dynamic equation of the single-rotor ducted UAV are deduced according to the structure of the single-rotor ducted UAV.Then,through mechanical analysis,under certain reasonable assumptions,the mathematical model of the ducted UAV is introduced,and the corresponding Simulink model is established based on this model.Secondly,considering that bypass UAV is a complex nonlinear system that is difficult to model accurately,and the immunity is poor,this paper designs the automatic disturbance rejection controller as the control system of the bypass UAV,and completes the attitude angle tracking experiment,immunity experiment and robustness experiment,which verifies the effectiveness of the automatic disturbance rejection controller as the control system of the ducted UAV.Then,Aiming at the problem of excessive parameters and difficult parameter tuning of the ADRC controller,the RBF neural network algorithm is used to automatically optimize the parameters of the ADRC controller.Through MATLAB/Simulink simulation experiments,the attitude angle tracking experiment,immunity experiment and robustness experiment are completed,which verifies that the improved automatic disturbance rejection controller is better in attitude tracking and immunity than before the improvement.Finally,according to the layout and characteristics of the ducted UAV,the parameters and selection of key components such as flight control,motor,propeller,ESC,steering gear,and digital radio station were determined,and the ducted UAV was built.A flight test platform for drones.Analyze and design the software program part of the ducted UAV,including software development tools,flight control ground station system,PX4 module,flight control program flow,etc.The effectiveness of the ducted UAV active disturbance rejection controller is verified by flight tests.In this paper,the mathematical model of bypass UAV is established,and the bypass UAV ADRC controller is designed,and the RBF neural network is used to improve it,the performance of the ADRC controller is verified by simulation experiments,and the flight test platform of the bypass UAV is built,the flight control software code is written,and the effectiveness of the ADRC controller is verified through flight test.