Measurement augmentation based fast initial alignment of SINS

In order to study how the information of accelerometers and gyros affect the speed of initial alignment of SINS. The system observation functions with different measurements are established according to the system principle. After the calculation of the measurements corresponding to different observable statements combinations, the observability of different statements based on different measurements combinations are analyzed. Several statements estimation convergence are compared while using different measurements combinations. Then the test verified the accuracy of the analysis sufficiently. Both analysis of observability and the test result show that the information of equivalent specific force errors cannot speed up the estimation of azimuth misalignment angle. The information of gyros errors can speed up the estimation of misalignment angles, while the estimation of azimuth misalignment angle can be speeded up only with the information of equivalent east gyro error.