基于多磁力计融合的电子罗盘研究

Research on Electronic Compass Based on Fusion of Multiple Magnetometers

为了提高电子罗盘的航向角测量精度和可靠性,提出了一种多磁力计的电子罗盘架构,并利用地磁场和磁力计空间约束关系对基于递推最小二乘(RLS)法联合卡尔曼滤波(KF)的误差补偿与融合算法进行设计。首先,根据地磁场测量误差特性构建多磁力计误差模型,并利用RLS进行椭球拟合,得到误差补偿参数。然后,根据噪声协方差矩阵对同构多传感器数据进行KF迭代融合。最后,仿真和实测实验验证了多磁力计模型与补偿融合算法的有效性,最终航向角测量精度在±0.5°以内,标准差小于0.2°,与单磁力计相比精度提升3倍左右。

In order to improve the accuracy and reliability of electronic compass heading angle measurement,a multi magnetometer electronic compass architecture is proposed,and an error compensation and fusion algorithm based on Recursive Least Squares(RLS)combined with Kalman Filter(KF)is designed using the spatial constraints of the geomagnetic field and magnetometer.Firstly,a multi magnetometer error model is constructed based on the measurement error characteristics of the geomagnetic field,and RLS is used for ellipsoidal fitting to obtain error compensation parameters.Then,KF iterative fusion is performed on isomorphic multi-sensor data based on the noise covariance matrix.Finally,simulation and actual experiments have verified the effectiveness of the multi magnetometer model and compensation fusion algorithm.The final heading angle measurement accuracy is within±0.5°,with a standard deviation of less than 0.2°,which is about three times higher than that of a single magnetometer.