Research on joint calibration and compensation of the inclinometer installation and instrument errors in the celestial positioning system

Abstract

AbstractThe application of celestial navigation based on inclinometer to aircraft in near‐earth space and planetary rovers is a significant development direction. Due to the installation and instrument errors of the inclinometer, it is difficult for tilted platforms to obtain high‐precision positioning results. But the installation error of the inclinometer is coupled with the error of the instrument itself, and there is no effective way to measure the two errors separately. To improve the positioning accuracy of the tilted platform, a joint calibration and compensation algorithm of the inclinometer's installation and instrument errors is proposed. First, based on the principle of celestial positioning, the influence analysis model of the inclinometer error on the positioning accuracy is built according to the definition of inclinometer installation error and instrument error, which indicates the traditional algorithms are not suitable for tilted platforms. Then, a joint calibration and compensation algorithm for the inclinometer installation and instrument errors is presented based on coordinate transformation relationship and error propagation characteristics. Finally, a ground test platform is built and the experimental verification of the joint calibration and compensation algorithm of inclinometer error is accomplished. Experiment results show the root mean square errors of the longitude and latitude are and , and the mean distance error is 397.46 m, which is far less than the mean distance error 3629.27 m of the traditional calibration algorithm. It indicates the joint calibration and compensation algorithm can effectively compensate for the errors caused by the inclinometer and obtain higher positioning accuracy.