Research On Design Of Quadrotor Aircraft Platform And Auto Disturbance Rejection Attitude Control Method

Unmanned aerial vehicle(UAV)is mainly contains several types,which is multi-rotor and fixed wing and hybrid wing.Among them,the muti-rotor UAV is widely used in actual life and scientific research because of its strong maneuverability,simple structure,easy operation,and small size.Quadrotors are the most common among multi-rotor drones.In this paper,take quadrotor as the research object and build a complete quadrotor UAV system,including the design of flight control software,the design of state estimation system,and the design of the ground control station and the attitude controller based on auto disturbance rejection is studied,which improves the disturbance rejection performance and stability of attitude control.Firstly,the nonlinear mathematical model of the quadrotor UAV is established.The coordinate system required by the UAV is introduced.The force analysis of the four-rotor UAV is carried out according to the body layout and control principles.The attitude dynamics and position kinematics model of the UAV are established according to the Newton-Euler equation.Secondly,a physical experiment platform including the flight platform hardware,embedded flight control software and ground control station software was built.In terms of hardware,various devices and sensors are selected and assembled according to the experimental requirements and performance requirements of the drone.Embedded flight control software mainly includes state estimation,attitude control,communication link design,and fault protection.The ground station software implements online real-time status monitoring and online parameter adjustment,map display and waypoint design,serial port assistant,three-dimensional status display and sensor correction functions.Thirdly,a state estimation system based on Kalman filter is designed,and an inertial sensor based on MEMS(Microelectromechanical Systems)is used to realize the attitude fusion and position velocity fusion system.First,the error model of IMU(Inertial Measurement Unit)is analyzed and calibrated.Then,a pose description method based on quaternion and its differential equations are introduced.Then,a separate attitude solution system based on extended Kalman filter and a position and velocity solution system based on multi-rate Kalman filter are designed.Finally,an attitude controller based on auto disturbance rejection is designed.Simulation experiments and physical experiments were carried out to verify the control of the auto disturbance rejection controller,and the particle swarm optimization algorithm was used to optimize multiple parameters of the extended state observer in the auto disturbance rejection,which made the extended state observer more effective.Observe the performance quickly.The results show that the designed controller has good disturbance suppression ability,which improves the control quality and stability of the system.