大方位失准角条件下的GPS/INS动基座初始对准

针对大失准角条件下初始对准难的问题，提出了一种新的大方位失准角下的GPS/INS组合导航初始对准方法。充分利用GPS提供的外部信息，以失准角的正余弦函数误差为状态变量，分析了GPS杆臂对初始对准的影响。并以上述工作为基础，提出了改进的滤波补偿算法。所提方法不仅可补偿大方位失准角，且可在方位角计算精度较低情况下直接进行导航解算，不需等待对准过程结束。在车载试验中，将该方法与传统小失准角前提下的对准方法进行了对比，并对对比结果作了分析。结果表明，在大失准角情况下，该方法可在100 s左右完成对准，失准角可收敛到1°内，导航位置误差可控制在2 m内。

Initial Alignment of GPS/INS Moving Base With Large Misalignment Angle

In view of the difficulty of initial alignment under the condition of large misalignment angle, a new initial alignment method of GPS/INS navigation system is proposed in this paper. Taking full advantage of the external information provided by GPS and using the error of the cosine function of the misalignment angle as the state variables, the effects of the GPS lever arm on the initial alignment are analyzed. On the basis of the above work, an improved filter compensation algorithm is proposed. The proposed method can not only compensate for the azimuth misalignment angle, but also can directly solve for navigation under the condition of the low precision of azimuth calculation, without waiting for the alignment process to be end. In the on vehicle test, the comparison between the new method and the traditional alignment method under the premise of small misalignment angle is carried out and the results are analyzed. The results show that this method can complete the alignment within about 100 s under the condition of large misalignment angle, the misalignment angle can converge within 1°, and the navigation position error can be controlled within 2 m.