Abstract: The design of viewport windows is a key link of designing ground regulator of star senor. It has an effect on adjusted precision of ground regulator of star senor. The viewport window is distorted when it is extruded. The distortion and medium can warp light path, so the star senor that cannot receive the original light will have bad adjusted precision. The dissertation is about a way to solve the problem using the ANSYS and MATLAB. The method can simulate the distortion of viewport and calculate the actual light path, so the method can provide the parameters for compensation of ground regulator of star senor.

Key words: Star senor, Viewport, Distortion of rigid body, Light path analysis, Fitting