捷联惯导在轨标定算法研究

On-Orbit Calibration for Strapdown Inertial Navigation System

为了保证长期在轨工作的捷联惯性导航系统的精度,设计了一种捷联惯导在轨标定算法。通过分析捷联惯导的主要误差源,建立了标定误差模型和导航误差模型。用加速度计的零位漂移、陀螺仪的零位漂移、陀螺仪的标度因数误差和安装误差构造系统状态方程,利用卫星导航系统提供的速度、位置信息和星敏感器提供的姿态信息构造量测方程,经过滤波运算得到各项误差估计值。算法解决了捷联惯导与星敏感器坐标轴不重合的问题,提高了嵌入式计算机的计算能力。最后对算法进行了数学仿真,仿真结果证明了算法的有效性。

In order to ensure the accuracy of the strapdown inertial navigation system for long-term work,an on-orbit calibration algorithm was designed.By analyzing the main error sources of strapdown inertial navigation,a calibration error model and a navigation error model were established.The system state equations were construct with the zero drift of the accelerometer,the zero drift of the gyroscope,the scale factor error and the installation error of the gyroscope.The speed,position information provided by the satellite navigation system and the attitude information provided by the star sensor were used to construct the measurement equations.The error values can be estimated through filtering operations.The algorithm solves the problem that the coordinate axes of SINS does not coincide with star sensor,and improves the computing power of the embedded computer.Simulation results indicate the feasibility of the on-orbit calibration algorithm.