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The high dynamic flight characteristic of space vehicles may lead to a significant variation of the installation errors and the scale factor errors of the inertial measurement unit (IMU). If the errors can't be calibrated and compensated, it may reduce the navigation precision of the inertial navigation system (INS) seriously. A method to dynamically identify the parameter of the installation errors and the scale factor errors was proposed. An augmented error model of the IMU including the installation errors and the scale factor errors of the IMU was built. Based on the Kalman filter, the dynamic parameter identification of the installation errors and the scale factor errors was designed. The observability of the installation errors and the scale factor errors with different maneuvers was analyzed. The simulation results show that the proposed dynamic identification method can effectively calibrate the installation errors and the scale factor errors online. With the calibrated results, the IMU errors are compensated and the precision of the INS is improved significantly. [ABSTRACT FROM AUTHOR]

In the traditional INS/CNS integrated algorithm, the system noise is correlated with the measured noise because the celestial observation output couples the horizontal platform benchmark error. To fix this problem, the principle of using celestial observation to modify gyroscope excursion was analyzed, and an aerospace vehicle positioning and navigation theme based on directly sensing horizon to achieve celestial analytical positioning and integrated filtering was proposed, then the relevant integrated filter model was built. In the theme, an inertia benchmark was built by star sensor and gyro, then celestial positioning based on infrared horizon sensor was calculated, and at last the INS/CNS integrated filtering was implemented. This theme fully takes the advantage of the accurate celestial information and succeeds in making the system noise and the measured noise independent. The simulation results show the validity of the proposed theme. [ABSTRACT FROM AUTHOR]