AUTONOMOUS OPTICAL GUIDANCE AND NAVIGATION STRATEGY AROUND A SMALL BODY

An impending demand for exploring small bodies such as comets and aste roids initiated the Japanese MUSES-C mission to the near-Earth asteroi d Nereus, where it will touch down on the surface. Autonomous optical guidance and navigation strategies around the asteroid is discussed, A n aligned intercept guidance that enables the approach from the prescr ibed direction is built, together with some important guidance propert ies associated with it. Among them, a combined range-estimation techni que using corrections without a range sensor is derived. The robust fe ature of the closed-loop guidance scheme is stressed. For the first ti me concrete strategies for such missions to small bodies are presented , Some comprehensive numerical illustrations, including gravity effect s, are given from the MUSES-C mission to support the discussion.