光纤捷联惯性测量组件在无安装基准时标定方法

Calibration for Strapdown Inertial Measurement Unit Without Orientation Adjustment

为了提高光纤捷联惯性测量组件(IMU)在没有安装基准时的标定精度,推导IMU在存在安装误差时的精确测量模型,采用粗、精两级结合标定的方法进行标定.粗标定采用传统的6位置标定编排,精标定按回归D最优原理设计了试验编排方案,并对测量模型参数进行带约束条件寻优,以粗标定的结果为寻优时的初值.实验结果表明,该方法能准确估计出IMU在转台上的安装误差角及测量模型中的各参数项,达到了IMU安装时不需要调平和对准也能实现精确标定的目的.经多次重复实验发现,"30位置"标定编排拟合误差最小,复相关系数最大,可作为系统的最佳标定方案.

A new calibration method that can increase the estimation accuracy of strapdown inertial measurement unit（IMU）＇s model parameters is described when the IMU＇s axes were not oriented precisely with respect to the axes of a tri-axial turntable.An accurate mathematical model was derived firstly.Then a test scheme,which was a combination of the coarse and precise calibration attempts to find the optimized values of the model＇s parameters,was introduced to minimize the error by starting at an initial parameter estimation of the coarse calibration.Test results showed that this calibration method can estimate the installation error and parameters of IMU model precisely without orientation adjustment.The best calibration method is found to be the＂30-position＂ calibration arrangement.