Astronomical calibration and spatial registration of multi-sensor

In order to achieve the spatial registration of multi-sensor on the same platform for astronomical observation, a camera calibration and attitude measurement algorithm was proposed based on the star image simulation which includes four steps. Firstly, according to star observation model and star catalogue, the simulated star image was produced in order to transform constellation features into image features. Then, based on the invariant collinearity of quadrilateral diagonal, image features between the observed star map and the simulated star image were matched, consequently, the initial values of the camera parameters could be extracted. Through using the singular value decomposition method, all the remaining control points were matched automatically and the attitudes of cameras were calculated. Finally, a complicated nonlinear optimization on camera intrinsic parameters and attitude matrix was required for this algorithm. The experimental result indicates that the re-projection error between different cameras is better than 1 pixel, and the correct recognition rate is more than 97.4% when the calibrations of optical system parameters are imprecise. This method can meet the requirements of accuracy and robust in registration of multi-sensor astronomical observation system.