Analytic coarse alignment and calibration for inertial navigation system on swaying base assisted by star sensor

Abstract

Initial alignment and positioning assisted by star sensors have been a popular research direction for the inertial navigation system. In this study, an analytic method is proposed to achieve the integration implementation of coarse alignment, calibration and positioning for swaying base. Gyroscope bias, accelerometer bias and attitude estimations are given in analytical forms on the basis of the attitude matrix provided by the star sensor. Positioning can be realised by transforming the accelerometer calibration part when the position information is not available. Compared with the previous approaches, the proposed method establishes the intuitive relationship between the navigation parameters and sensor errors, and is easy to implement. Furthermore, the proposed method can be extended to moving base when the velocity measurement is available. Both the simulation and experimental results show that the proposal analytic method can provide both good initial attitude and sensor parameters for fine alignment process.