Calibration of magnetometer is an essential part to obtain high measurement precision.However,the existing calibration methods are basically the calibration of all attitudes,which means tough work when the magnetomete...Calibration of magnetometer is an essential part to obtain high measurement precision.However,the existing calibration methods are basically the calibration of all attitudes,which means tough work when the magnetometer is applied in strapdown inertial navigation system(SINS).So a quick,easy and effective calibration algorithm is developed based on the ellipsoid constraint to calibrate magnetometers.In this paper,the measuring principle and error characteristic of the magnetometer are analysed to study its magnetic interference.During the process,a magnetometer calibration model is set up to convert the calibration to ellipsoid fitting based on the characteristic of hard magnetic interference and soft magnetic interference.Then the algorithm is tested by mimic experiment.The result shows that measurement precision is improved after the calibration,and then the magnetometer is installed in a control cabin of an underwater robot which is designed and developed by us,and actual magnetometer calibration experiments are conducted to further verify the validity of the algorithm.展开更多
An effective and flexible rotation and compensation scheme is designed to improve the accuracy of rotating inertial navigation system （RINS）. The accuracy of single-axial R1NS is limited by the errors on the rotatin...An effective and flexible rotation and compensation scheme is designed to improve the accuracy of rotating inertial navigation system （RINS）. The accuracy of single-axial R1NS is limited by the errors on the rotating axis. A novel inertial measurement unit （IMU） scheme with error compensation for the rotating axis of fiber optic gyros （FOG） RINS is presented. In the scheme, two couples of inertial sensors with similar error characteristics are mounted oppositely on the rotating axes to compensate the sensors error. Without any change for the rotation cycle, this scheme improves the system＇s precision and reliability, and also offers the redundancy for the system. The results of 36 h navigation simulation prove that the accuracy of the system is improved notably compared with normal strapdown INS, besides the heading accuracy is increased by 3 times compared with single-axial RINS, and the position accuracy is improved by 1 order of magnitude.展开更多
基金Supported by the National High Technology Research and Development Programme of China(No.2011AA04201)
文摘Calibration of magnetometer is an essential part to obtain high measurement precision.However,the existing calibration methods are basically the calibration of all attitudes,which means tough work when the magnetometer is applied in strapdown inertial navigation system(SINS).So a quick,easy and effective calibration algorithm is developed based on the ellipsoid constraint to calibrate magnetometers.In this paper,the measuring principle and error characteristic of the magnetometer are analysed to study its magnetic interference.During the process,a magnetometer calibration model is set up to convert the calibration to ellipsoid fitting based on the characteristic of hard magnetic interference and soft magnetic interference.Then the algorithm is tested by mimic experiment.The result shows that measurement precision is improved after the calibration,and then the magnetometer is installed in a control cabin of an underwater robot which is designed and developed by us,and actual magnetometer calibration experiments are conducted to further verify the validity of the algorithm.
基金supported by the National Natural Science Foundation of China (No.40904018)the Key Laboratory Foundation of the Ministry of Education of China (No.201001)the Doctoral Innovation Foundation of Naval University of Engineering (No.BSJJ2011008)
文摘An effective and flexible rotation and compensation scheme is designed to improve the accuracy of rotating inertial navigation system （RINS）. The accuracy of single-axial R1NS is limited by the errors on the rotating axis. A novel inertial measurement unit （IMU） scheme with error compensation for the rotating axis of fiber optic gyros （FOG） RINS is presented. In the scheme, two couples of inertial sensors with similar error characteristics are mounted oppositely on the rotating axes to compensate the sensors error. Without any change for the rotation cycle, this scheme improves the system＇s precision and reliability, and also offers the redundancy for the system. The results of 36 h navigation simulation prove that the accuracy of the system is improved notably compared with normal strapdown INS, besides the heading accuracy is increased by 3 times compared with single-axial RINS, and the position accuracy is improved by 1 order of magnitude.
