MEMS-IMU构型设计及惯性器件安装误差标定方法

MEMS-IMU configuration and its inertial sensors’ calibration for installation errors

提出一种由三只单轴MEMS陀螺仪和三只单芯片双轴6个加速度计构成的MEMS-IMU配置方案。针对该方案的特点,研究了基于重力参考矢量对MEMS惯性器件安装误差的标定方法。该方法的关键是利用同一安装平面内的两个加速度计测量矢量的叉乘矢量的方向代替MEMS陀螺敏感轴方向,利用两轴或三轴角位置转台标定MEMS-IMU中惯性器件的安装误差。分析了标定矩阵的求逆条件数,提出了3位置和6位置的标定,指出了多位置标定中转台姿态角度的选择范围。新型MEMS-IMU配置方案及安装误差标定方法可有效解决MEMS-IMU惯性器件安装误差的标定与补偿问题。

A configuration scheme for MEMS-IMU was presented, in which the MEMS-IMU was composed of 6 accelerometers with three single-chips and two-axis, and three single-axis MEMS gyroscopes. The calibration method for MEMS sensors installation errors based on gravity reference vector was investigated. The key of this method is to use the direction of vector cross product of the two-axis MEMS accelerometers as a replace of the sense-axis direction of the MEMS gyroscope, and it can be done under the condition that only a 2 or 3 DOF angle-position turntable is available. The condition number with respect to inversion of calibration matrix was analyzed. The calibrations for 3- and 6-position were presented, and the attitude angle range of turntable in multi-position calibration was pointed out. The novel configuration scheme and calibration method can effectively solve the problems of calibration and compensation of installation errors in MEMS inertial sensors.