基于改进最小二乘与信任域Dogleg法的磁力计标定  

Magnetometer calibration based on improved least squares and trust domain Dogleg method

作　　者：崔照林 余未 倪屹 潘云清 CUI Zhaolin;YUWei;NI Yi;PAN Yunqing(Engineering Research Center of IoT Technology Applications(Ministry of Education),Wuxi 214122,China;School of Integrated Circuits,Jiangnan University,Wuxi 214122,China;Wuxi Beiwei Sensing Technology Co.,Ltd.,Wuxi 214072,China)

机构地区：[1]物联网技术应用教育部工程研究中心,江苏无锡214122 [2]江南大学集成电路学院,江苏无锡214122 [3]无锡北微传感科技有限公司,江苏无锡214072

出　　处：《空天预警研究学报》2024年第3期202-208,共7页JOURNAL OF AIR & SPACE EARLY WARNING RESEARCH

摘　　要：在三轴磁力计标定过程中,针对采样点不丰富时传统最小二乘(LS)椭球拟合方法精度较差以及磁力计与加速度计轴向不对准的问题,提出了一种改进LS与信任域Dogleg法结合的标定方法.首先根据磁力计的误差模型,运用改进的LS算法进行椭球拟合;然后利用重力矢量和地磁矢量之间点积恒定的性质,构建未对准误差的数学模型;最后采用信任域Dogleg算法估计这些误差参数.仿真和实验结果表明,利用改进LS法估计这些误差参数时,误差范围达到了10-6量级;磁矢量模值均方根误差相比LS减小了88.5%,有效提高了传统拟合方法的精度;轴向对准后,最终航向角测量精度在±0.8°以内,均方根误差小于0.5°,明显小于对准前的误差,证明了信任域Dogleg算法的有效性.Aiming at the poor accuracy of the traditional least square(LS)ellipsoid fitting method and the axial misalignment of magnetometer and accelerometer when the sampling points are not abundant in the process of three-axis magnetometer calibration,this paper proposes a calibration method combining improved LS with trust domain Dogleg method.Firstly,according to the error model of magnetometer,the improved LS algorithm is used to fit the ellipsoid.Then,the mathematical model of misalignment error is constructed by using the property of dot product constancy between gravity vector and geomagnetic vector.Finally,the trust domain Dogleg algorithm is used to estimate these error parameters.Simulation and experimental results are shown as below:When the improved LS method is used to estimate these error parameters,the error range reaches the order of 10-6.The root-mean-square error of the magnetic vector modulus is reduced by 88.5%compared with LS,which effectively improves the accuracy of the traditional fitting method.After axial alignment,the measurement accuracy of final heading angle is within±0.8°,and the root-mean-square error is less than 0.5°,significantly smaller than the error before the alignment,which proves the effectiveness of the trust domain Dogleg algorithm.

关 键 词：磁力计标定 最小二乘算法 信任域Dogleg方法 椭球拟合 非线性优化 

分 类 号：V241.6[航空宇航科学与技术—飞行器设计] TN967.2[电子电信—信号与信息处理]