箭载捷联惯导系统水平自对准的两种实用方法

Two practical methods of autonomous leveling alignment for launch vehicle SINS

箭载惯导系统的方位对准一般通过外界直接瞄准装订,而水平对准利用惯导系统的惯性器件测量和计算来实现。在运载火箭初始对准过程中,箭体受发射场阵风等干扰因素的影响而使得惯导系统产生角晃动与线晃动,水平对准方法必须具备抗晃动干扰的能力。根据运载火箭初始对准中的水平姿态角及其变化比较小的特点,建立了俯仰角与偏航角之间相互解耦的对准误差方程。提出了应用控制原理和数字滤波进行水平对准的两种方法,计算机仿真表明了这两种方法有效可行。与传统的卡尔曼滤波对准相比,本文的方法具有运算简单、计算量小和便于工程应用等优点。

The azimuths of launch vehicle＇s strapdown inertial navigation system （SINS） are usually aligned by using external direct aiming methods, while the leveling attitudes are calculated and implemented by inertial measurements of SINS. During the initial alignment stage, the launch vehicle＇s SINS would undergo angular and linear swaying under various disturbance environments, such as ground winds. Therefore, its leveling alignment methods must have the ability to eliminate disturbance. Based on the launch vehicle＇s characters of small leveling attitudes and little changes, the de-coupling alignment error equations for pitch and azimuth angle were established. Two methods for leveling alignment using control theory and digital filtering were introduced in detail. The simulation results show that the methods are available and have the advantages of simple operation, low calculation burden and convenience for applicability compared with the traditional kalman filter alignment.