The Study Of The Magnetic Interference Compensation Algorithm Of Underwater Robot

It is very promising to use the underwater robot to measure the geomagnetic field for navigation and reconnaissance in the field of space navigation.The advantage of geomagnetic field navigation lies in its passiveness and concealment.However,underwater vehicle carriers or other underwater vehicles are mostly made of ferromagnetic materials,and the equipment in carrier i also equipped with electronic equipment,which interfere with the measurement of the magnetometers and affect the measurement accuracy.Therefore,it is necessary to compensate the error that the underwater robot carrier can interfere with the magnetometer.In this paper,as the background,in view of the interference characteristics of underwater robot carrier to magnetometer,the compensation methods of different types of interference in the measurement of three-axis magnetometer are studied.The main work includes: According to the structure and movement characteristics of the underwater vehicle,the magnetic field interference source and its characteristics are analyzed.The leakage magnetic field of the brushless DC motor is mainly analyzed,and the static magnetic field characteristics and dynamic magnetic field characteristics of the underwater vehicle carrier are analyzed.According to the influence of random disturbance of the triaxial magnetometer in measurement process,two methods of low-pass filtering and wavelet denoising are proposed,and the simulation of these two methods are carried out.Since wavelet denoising is mainly used to remove high-frequency interference signals,there are limitations on the errors existing in the three-axis magnetometer and the elimination of some low-frequency interference errors.Based on the measurement model of three-axis magnetometer,the error model is constructed and the error compensation formula is obtained.The recursive least square method and extended Kalman filter method are proposed to estimate the error parameters.The simulation of these two methods are carried out.Finally,in order to verify the effectiveness of the wavelet denoising and triaxial magnetometer compensation algorithm,an underwater robot is proposed as an object,and an experiment is set up for experimental verification.