基于杆臂补偿的多MIMU六方位倍速率标定方法

误差建模、标定与补偿是提高微惯性测量单元(MIMU)精度的关键,而杆臂效应是影响低成本微机电系统(MEMS)惯导精度进一步提升的瓶颈。针对杆臂效应引起的多MIMU标定误差问题,提出了一种基于杆臂补偿的多MIMU六方位倍速率标定方法。分析了杆臂效应影响多MIMU标定的误差机理,设计了一种六方位倍速率标定方案,建立了基于杆臂补偿的误差系数标定解算模型,补偿了杆臂效应引起的标定误差,并应用加权最小二乘法对MIMU加速度通道和角速度通道的非对称性误差进行了抑制。试验结果表明,与现有六方位正反速率标定方法相比,采用该方法的MIMU加速度通道补偿误差降低了84%,角速度通道补偿误差降低了68%。

Six-position Multiplied Rates Calibration Method Based on Lever Arm Compensation for Multi MIMUs

Error calibration compensation is the key technology to improve MIMU precision.The effect of lever arm is a bottleneck that restricts the accuracy improvement of low-cost MEMS inertial navigation. Aiming at the problem of multi-MIMU calibration error caused by lever arm effect, a multi-MIMU calibration method based on lever arm compensation is proposed. The error mechanism of multi-MIMU calibration is analyzed. A six-position multiplied rates calibration scheme is designed. A calibration model of error coefficient based on lever arm compensation is established to compensate the calibration error caused by lever arm effect. The weighted least square method is applied to suppress the asymmetric errors of MIMU acceleration channel and angular velocity channel. The experimental results show that the error of the MIMU acceleration channel is reduced by 84% and the error of the angular velocity channel is reduced by 68% using the proposed method, compared with the traditional six-position positive and negative rate calibration method.