基于大失准角时变参数罗经初始对准算法

为了解决大失准角条件下的捷联惯导初始自对准问题,通过分析捷联惯导系统大失准角误差模型,利用平台惯导系统罗经对准原理,提出了一种新的捷联惯导系统罗经对准方案。该方案的具体实现划分为三个阶段:方位角未知情况下的水平对准;大失准角时变参数罗经方位对准;定参数罗经对准。该方案通过实时调节罗经参数缩短了对准时间;利用大方位失准角模型代替小失准角模型,在算法收敛阶段更加准确地描述了捷联惯导系统的误差传递方式。仿真试验表明,使用陀螺随机漂移稳定性为0.01(°)/h的捷联惯导系统,该对准方案能在60 s内方位精度到达1°,并能在对准结束时达到3’的方位对准精度。

Variable parameter gyrocompass alignment algorithm based on large error angle model

To solve the initial self-alignment problem of strapdown inertial navigation system(SINS) under large error angle condition,a new gyrocompass alignment scheme is put forward by analyzing SINS large error angle model and based on the principle of compass effect in platform inertial navigation system(PINS).The scheme can be divided into three steps: horizontal alignment with azimuth angle uncertainty;time-vary parameter gyrocompass alignment for large error angle;fixed parameter gyrocompass alignment.Converge time can be shorten by adjusting gyrocompass parameter in real time in this scheme.A more accurate error transfer mode in strapdown inertial navigation system(SINS) is depicted by large azimuth error angle model instead of small error angle model.At last,a simulation is made using this scheme which shows that the gyro bias is stabilized at 0.01(°)/h,and azimuth precision can reach in 60 s and at end of alignment.