IMU 姿态误差均衡校正模型与验证

惯性姿态测量单元(IMU)中存在各种系统误差,需要进行校正以提高姿态解算精度,而校正矩阵是由本身包含各种系统误差的特殊位置测量值及其理论值决定的。对校正矩阵产生的校正误差进行理论推导,研究其对解算姿态参数误差的影响特征,并用测试数据进行验证。根据均衡校正点的设计,详细研究均衡校正及其结构拓扑对姿态精度的影响模型和特征,并对测试数据进行均衡校正验证,典型姿态解算结果及对比表明,均衡校正普遍降低了姿态的绝对误差,均衡平均校正最少可降低解算姿态绝对误差的平均值和峰峰值至30.8%,且在小倾斜角区域也达到大中倾斜角区域常规校正的姿态解算精度。

Balance correction and verification of IMU posture error

There are various system errors in the inertial measurement unit ( IMU). It needs calibration to enhance the accuracy of attitude calculation. The correction matrix is usually determined by the measurement values and their theoretical values at some specially designed positions where the measurement values of sensors also contain various system errors. The error caused by the correction matrix is deduced theoretically, and its influence on the error of attitude parameters is studied. Experimental data are utilized to verify those influences. According to the point design of balance correction, the influence models of balance correction and its structure topology on attitude accuracy are researched in detail. The balance correction is again implemented on the original experiment data. The results at some classic attitude positions show that the balance correction generally reduces the absolute error. The average and peak values of absolute attitude error are decreased to 30. 8% at least with the average balance correction. Moreover, the attitude accuracy of small inclination angle with the average balance correction occupies the similar attitude accuracy under large and medium inclination angles with the traditional correction method.