Research On The Attitude And Navigation Information Fusion Algorithm Of Multi-Rotor Aircraft

Multi-rotor aircraft has a wide range of applications,Obtaining the accurate attitude of the aircraft is the primary condition for precise control of flight.However,the attitude estimation of a multi-rotor aircraft will produce deviations in the magnetic interference environment.In order to solve the above problems,this paper studies the fusion algorithm of attitude and navigation information based on the self-developed flight control system to improve the accuracy of the attitude information and the engineering practicability of the multi-rotor aircraft.The following aspects are mainly studied:(1)The measurement characteristics of the sensors are analyzed,and the working characteristics of the attitude and navigation sensors of the aircraft are studied in depth,which lays the foundation for the research of the attitude and navigation fusion algorithm.(2)The multi-level structure of multi-rotor attitude and navigation information fusion is established.The attitude estimation of inertial measurement unit(IMU),the position and velocity estimation of accelerometer,the position and velocity estimation of GPS,and altitude information of barometric altimeter are studied.(3)The INS/GPS integrated navigation system is studied,and the combined navigation information two-level data fusion scheme is designed.The first level is attitude information fusion.The gyroscope,accelerometer and magnetometer are used to obtain the attitude angle of the aircraft,and the commonly used attitude estimation algorithm is theoretically derived and analyzed.This paper focuses on the Kalman Filter,which is the most widely used in the information fusion algorithm.Aiming at the attitude estimation in the magnetic interference environment,the improved Kalman Filter provides reliable attitude information for INS / GPS integrated navigation system.(4)The second level is position and velocity information fusion.The horizontal position and vertical height of the multi-rotor aircraft are obtained by using the extended Kalman Filter fusion accelerometer,GPS and barometer to estimate the position information.Based on the self-developed flight control system,the improved Kalman Filter is verified.The results show that the algorithm can improve the attitude estimation accuracy of the multi-rotor aircraft in the magnetic interference environment and enhance the anti-magnetic interference performance of the multi-rotor aircraft.The positioning accuracy of the integrated navigation system meets the actual requirements of the multi-rotor aircraft.