三轴磁强计与MEMS陀螺的在轨实时标定方法  

Real-time on-orbit calibration method for three-axis magnetometer and MEMS gyroscope

作　　者：向甜[1] 王昊[2] 蒙涛[2] 金仲和[2] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027 [2]浙江大学航空航天学院,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2014年第3期541-547,共7页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(60904090)

摘　　要：为了提高基于磁强计和微电子机械(MEMS)陀螺的微小卫星定姿系统的精度,提出在无姿态信息时仅依靠三轴磁强计以及MEMS陀螺的测量信息来实时标定磁强计以及MEMS陀螺的算法.该策略采用无迹卡尔曼滤波(UKF)算法,将磁强计的偏置、刻度因子与非正交误差矩阵以及MEMS陀螺漂移作为状态向量,通过建立基于三轴磁强计及其惯性坐标系磁场矢量的观测方程,以及相应的微分测量方程,实现三轴磁强计与MEMS陀螺的在轨标定.仿真结果表明:通过标定后,磁强计的三轴偏置估计误差均优于0.02mG,刻度因子与非正交误差矩阵的六要素估计误差均优于1×10-4,而MEMS陀螺三轴漂移估计误差分别为1.5°/h、0.45°/h和0.94°/h,从而验证了本策略的可行性.In order to improve the accuracy of the attitude determination system（ADS）for micro-satellites based on three-axis magnetometer（TAM）and micro electro mechanical systems（MEMS）gyroscopes,a real-time calibration algorithm for the magnetometer and MEMS gyro was introduced by using only the TAM and MEMS gyro measurements.The unscented Kalman filter（UKF）was applied as the estimation algorithm,in which the TAM bias,the matrix of its scale factors and non-orthogonality corrections,and the gyro drift were used as the state vectors.Then the TAM and geomagnetic vectors in its inertial coordinate based observation model,together with their corresponding derivative measurement model,were established to realize the on-orbit calibration.The simulation indicated that the estimation errors of the TAM bias were smaller than 0.02mG after calibration,while those of the six elements in the matrix of the scale factors and non-orthogonality corrections were all smaller than 1×10-4,and the estimation errors of the gyro bias were 1.5°/h,0.45°/h and 0.94°/h respectively for each axis,which verified the feasibility of the proposed strategy.

关 键 词：MEMS陀螺 三轴磁强计 在轨标定 UKF算法 

分 类 号：V448.22[航空宇航科学与技术—飞行器设计]