A study on attitude motion estimation of a decommissioned spacecraft with visual tracking of feature points

Today, space debris, which exists in large quantities in Earth's orbit, has become a serious problem, either as an obstacle to the launch of new spacecraft or as a collision hazard. Therefore, technology development to remove such debris has become an urgent issue. Out-of-service satellites or space structures are large among the debris, easily tracking them in orbit. In addition, the approximate physical parameters such as size and the nominal position of the center of gravity are often identified as mission design parameters. This study proposes a method to estimate the attitude motion of spacecraft based on real-time images. In the proposed method, the feature points of the target spacecraft are tracked using visual tracking, and the attitude motion of the spacecraft is estimated using a Kalman filter. This study assumed that the motion of the target spacecraft is pure-spin. This article reports a numerical example in which the attitude motion is estimated using the proposed method.