基于非线性变换的加速度计误差标定与补偿CSCD

为提高三轴加速度计测量精度,分析其误差来源和产生机理,建立了误差模型;根据误差模型和重力场幅值不变特性,推导出非线性观测方程。引入两个未知的参数向量,通过数学变换把非线性观测方程变形为关于新未知参数的线性方程;然后采用批量最小二乘法求出新的未知参数,并根据误差模型参数和新未知参数之间的关系,利用逆解析运算求出对应的零点偏差、灵敏度误差和三轴不正交误差。实验结果表明,加速度计正负误差峰值间距可以减小100倍左右,精度可达10-3m/s2,并具有很好的可重复性。该方法算法效率较高,补偿效果显著。

Error Calibration and Compensation of Three axis Accelerometer Based on Nonlinear Transform

In order to improve the three-axis accelerometer′s measurement accuracy, an error model is established based on its error source and producing mechanism. Nonlinear observation equation is deduced by the error model and constant amplitude of gravity field. Through introduced two unknown parameter vectors, nonlinear observation equation is mathematically converted into a linear form relative to new unknown parameter. Then batch least square method is used to estimate the new unknown parameters. Biases, scale factors and non orthogonal error are solved by inverse analytic arithmetic. The experimental results show that the maximum error of accelerometer can be reduced about 100 times and the accelerometer accuracy can reach 10^-3m/s². Experiments have good repeatability. The method is a high efficiency batch least-square method and the compensation effect is remarkable.