Abstract
Precise localization is important for a rover on small planetary bodies including asteroids and comets. Conventional localization methods are not adequate on small body surface because of the small body’s irregular shape and small mass. Localization by camera images obtained on-board will not match the resolution of the map made by the spacecraft. Celestial navigation has little accuracy because the gravity direction on the small planetary body can not be used as a standard direction. It is not realistic to arrange multiple navigation spacecraft near the small planetary body like GPS. In this paper, we propose a reasonable localization method of a rover for a small planetary body. It uses two-way range measurement between a rover and a mother spacecraft. The measurements are conducted repeatedly. This method is available to the whole surface of the planetary body while it needs only one spacecraft. Numerical simulations evaluated the localization accuracy on ITOKAWA-size-body whose radius is less than 1[km]. We also analyzed the influence of uncertainties in rotation parameters of a small body and position of a spacecraft on localization accuracy.
