star images

A novel method is proposed in the paper to obtain the high-precision estimation of the angular velocity and the star-spot’s centroid at the same time. First, the Radon transform on a single frame image is adopted to roughly estimate the initial value of angular velocity and the star-spot’s centroid based on the dynamic imaging and kinematic model. Then, theloss function of each star spot is constructed by combining two consecutive frames. Finally, the improved Levenberg-Marquardt method is employed to realize the precise estimation of each parameter, so as to obtain the high-precision star-spot’s centroid and angular velocity. The simulation experiments verify that the method has a minimum error of 6e-3 pixels of the estimation of star-spot’s centroid, about 2.4e-4 QUOTE

 of the estimation of the x,y direction angular velocity and about 1.8e-3

 of the estimation of z direction angular velocity. The experiments on actual star images the estimation precision of the method is better than the conventional method for different angular velocities, especially for the case of medium and high angular velocities, which is 5 times better than the conventional method.