垂线偏差对惯导系统位置误差的影响分析

针对制约高精度惯性导航系统精度的垂线偏差误差项问题,研究了垂线偏差对惯性导航系统水平位置误差的影响及各级惯导系统误差补偿时垂线偏差的指标需求。首先,推导了垂线偏差引起的惯导系统误差项的直接差分法和四阶龙格库塔数值更新算法,对比分析了两种算法在不同地区的水平位置误差的更新效果;然后,采用3种分辨率的垂线偏差网格数据对惯导系统进行补偿;最后,分析了垂线偏差补偿频率对位置误差补偿的效果并开展了车载导航DOV补偿实验。仿真及实验结果表明,两种误差更新算法都可以有效计算水平位置误差;垂线偏差最大可引起近3 000 m的位置误差,水平姿态误差与方位姿态误差1 h漂移约18″和72″;经DOV补偿后,水平定位精度提升了约230 m。

Analysis of the inertial navigation system positioning error caused by deflection of the vertical

To address the error problem of the deflection of the vertical(DOV),which restricts the precision of high-precision inertial navigation system(INS),the influence of DOV on the horizontalposition error of INS and the index requirements of DOV for error compensation of INS at all levels are studied. Firstly, the direct difference method and the fourth order Runge Kutta numerical updating algorithm of the INS error term caused by DOV are derived. The updating effects of the horizontal position errors of the two algorithms in different regions are compared and analyzed. Then, the INS is compensated with three kinds of resolution DOV grid data. Finally, the effect of DOV compensation frequency on position error compensation is analyzed and DOV compensation experiment of vehicle navigation is carried out. The simulation and experimental results show thatboth error update algorithms can effectively calculate the horizontal position error. The maximum DOV can cause a position error of nearly 3 000 m,and the horizontal attitude error and azimuth attitude error drift about 18" and 72" in 1 h. After DOV compensation,the horizontal positioning accuracy is improved by about 230 m.