基于双轴转台的捷联惯导系统姿态精度评定算法

Inertial Navigation System Attitude Accuracy Evaluation Algorithm Based on the Turntable/Strapdown

系统姿态精度是惯导系统的重要指标之一。针对系统的姿态精度,尤其是动态姿态精度因缺乏姿态基准而难以评定的问题,提出一种基于双轴转台的惯导系统姿态精度评定算法。首先对姿态误差角建模,利用惯导组件不同航向角所确定的旋转矩阵第三行三列的元素不含有航向角信息的特点,在无北向基准的情况下,求解出惯导和转台的安装误差角,进而得到惯导姿态误差,此姿态误差即可反映系统姿态精度,最后,进行了光纤惯导系统的精度评定试验。结果表明,算法在转台无需北向基准条件下可有效标定出惯导系统姿态误差和安装误差,其流程简单、适应性好,可为系统精度评定提供参考。

The attitude accuracy is one of the important indicatiors in inertial navigation system. For the attitude accu- racy problems, especially the difficulty in assessing dynamic attitude accuracy, an inertial navigation system attitude accuracy evaluation method based on turnable strapdown is proposed. Firstly, posing error angle is modeled, and the characteristic that the third line three columns element of the rotation matrix determined by different course angles don＇t contain the infor- mation of course angle, is used to compute the installation error angle between inertial navigation and table in the absense of north benchmark, thus obtaining the inertial attitude error which can reflect the attitude accuracy of the system. Finally, the accuracy evaluation test of optical fiber inertial navigation system is conducted. The result shows that the algorithm can effec- tively evaluate the attitude error and installation error of inertial navigation system without north benchmark, which has sim- ple process, good adaptability, and can provide reference for system accuracy evaluation.