Planet or Moon image processing for spacecraft attitude estimation

Abstract

A unique vision-based three-axis spacecraft attitude determination method using Moon or Earth observation images is introduced, which is able to operate in a stand-alone configuration. We describes the image data processing algorithms to extract the two directions needed from the observed images to estimate the spacecraft orientation. Since the image rotation and translation processes affect the attitude estimation result, the accuracy is quantified by analyzing the sensitivity of the two directions due to subpixel image translations and rotations. Furthermore, with the vision of a new Mars mission, an alternative image data processing algorithm for oblate bodies is presented. As for the attitude accuracy level that can be achieved, it highly depends on the image processing efficiency/complexity. Its numerical value, however, is not quantified because it would require unavailable real data.