基于四元数的SINS静基座大方位失准角误差建模

Establishment of Errors Model for SINS on a Stationary Base with Large Azimuth Misalignment Angle Based on Quaternion

针对经典大方位失准角条件下捷联惯导系统(SINS)非线性初始对准模型不能精确表达姿态误差的传播特性,依据惯导系统姿态的旋转矢量表示法,提出了基于四元数微分方程推导的姿态误差模型,模型最终的表达也由欧拉角微分方程给出。基于无迹卡尔曼滤波(UKF)的静基座对准试验表明新的姿态误差模型对方位角失准角范围要求由10°内放宽到25°内,提高了在大方位失准角条件下初始对准的精度,表明模型的准确性有明显提高。

The classical error model of SINS with large azimuth misalignment angle can not exactly express the error transmit characteristics. Since the rotation vector can describe the attitude of SINS, a new model was derived based on quaternions differential equation. The expressions of the new model were also given as euler angle differen tial equation. Test based on UKF on stationary base shows the new model can expand the range of azimuth misalignment angle from within lO°to within 25° and can get more superior alignment precision for initial alignment with large azimuth misalignment angle. The test result shows that the new model is more accurate.