GNSS/MEMS IMU车载组合导航中IMU比例因子误差的影响分析

Influence Analysis of IMU Scale Factor Error in GNSS/MEMS IMU Vehicle Integrated Navigation

从系统状态模型出发,分析比例因子误差对组合导航精度和计算量的影响,同时基于车载运动的特点分析比例因子误差的观测性,提出一种仅保留航向陀螺仪和水平加速度计比例因子误差的降维状态模型。实验结果表明,当比例因子误差大于6×10^(-3)时,增广比例因子误差有助于提高导航精度,但计算量增加约170%;降维模型能够达到高维模型的导航精度,与不增广比例因子误差相比,计算量仅增加约70%。

Starting from the system state model,we analyze the influence of scale factor error on the calculation amount and accuracy of integrated navigation.At the same time,based on the characteristics of vehicle motion,we analyze the observability of the scale factor error,and propose a dimensionality reduction state model that only retains the scale factor errors of the heading gyroscope and horizontal accelerometer.The experiments show that:when the scale factor error is greater than 6×10^(-3),augmenting the scale factor error can help improve navigation accuracy,but the calculation amount increases by about 170%;the reduced-dimensional model can achieve the navigation accuracy of the high-dimensional model,and the calculation amount is only increased by about 70% compared to that without augmenting scale factor error.