基于动态零速条件的动基座自对准

Self-alignment on moving base under dynamic zero velocity conditions

为增强车载捷联惯导系统的机动性和自主性,提出了一种基于动态零速条件的动基座自对准方法。利用车体坐标系横向和垂直方向上速度为零作为约束条件,构造卡尔曼滤波器;利用基于谱条件数的可观测度分析法对系统的状态量进行了可观测性分析,论证了卡尔曼滤波器设计的合理性。运动条件下的仿真结果表明:采用中等精度的惯导,在仿真时间不大于500s的情况下,方位对准精度8.86',水平对准精度优于1.46'。该方法算法简单,不需要辅助信息,具有很好的工程应用价值。

An initial alignment method on moving base under dynamic zero velocity condition was presented to improve the flexibility and independence of strapdown inertial navigation system（SINS） in vehicle.The Kalman filter was constructed,in which zero transverse and vertical velocities in vehicle body coordinate were taken as the constraint condition.The theory of spectral condition number was used to analyze the observability degrees of error states and determine the effect of Kalman filter.Some simulations using medium precision SINS were carried out on moving base.The results show that the azimuth alignment accuracy reaches about 8.86＇,and the level alignment accuracies are superior to 1.46＇when the whole alignment time is less than 500s.This method is not only simple in arithmetic,but also doesn＇t need auxiliary information.All this characteristics prove that this method is valuable in engineering application.