基于可观测度分析的捷联惯导初始对准方法

输出校正和反馈校正是捷联式惯导系统初始对准的两种传统方法,可观测度是衡量卡尔曼滤波状态估计效果的量度。为提高捷联惯导初始对准的精度,分析了状态的可观测度与反馈校正对初始对准精度的影响,得出状态的估计效果与使用的校正方法有关,正确的反馈量可提高估计精度。因此,该文提出了一种基于可观测度分析的自适应反馈校正方法,并分别使用3种校正方法进行地面静基座初始对准仿真实验,实验结果表明此方法可有效提高对准精度。

Initial Alignment Method for SINS Based on the Analysis of the Degree of Observability

The output compensation and feedback compensation are two traditional methods of the initial alignment strap down inertial navigation system (SINS). The degree of observability is the standard to evaluate the state of Kalman filter. For the purpose to improve the alignment accuracy, the effect of the degree of observability and the feedback compensation on the SINS alignment accuracy is analyzed. The conclusion shows that the state estimation result is related to the compensation method, and a proper feedback quantity can lead to a batter result. Based on this conclusion, a considerable adaptive feedback compensation method based on observability analysis is proposed. Finally, the method is proved to be efficient on improving the alignment accuracy by a simulate experiment in which three methods are used to do the initial alignment on the ground stationary base.