Technologies toward Lunar Crater Exploration

The primary challenge of descending steep, loose slopes is avoiding avalanche, tipover and maintaining control of locomotion. Theory suggests that for loose, granular soil,the strength lies under, not on, the surface. This has not hitherto been exploited for controlling robot descent. In order to take advantage of this, a prototype robot capable of utilizing sub-surface strength was developed and tested. Two unique features are low center-of gravity and an actuated plow capable of penetrating the ground for controlling descent and facilitating pivot. Tests show unprecedented control during descent on loose soil slopes up to 40 degrees. Avalanche sliding is reduced twenty-fold , pivot turning is improved threefold.