Under the micro-gravity environment such as on the surface of small planetary bodies (asteroids or comets), traditional wheeled rovers are not expected to move effectively due to the low friction and inevitable detachment from the surface. Therefore, the authors propose a hopping rover suitable for exploration on the surface of small bodies. This paper describes the micro-gravity experiments of a proposed hopping rover which is driven by an internal DC motor torque. The proposed rover could hop under a micro-gravity environment. Experimental results are compared with the computational simulations.

For evaluating the basic navigation techniques for a planetary rover on a natural terrain, long range navigation experiments had been performed at Mt. Mihara volcano of Izu-Ohshima Island in September of 1996. The experimental rover succeeded in traveling over 800 m autonomously without hitting any obstacle. This paper describes navigation functions installed in the test-bed rover. This paper also presents the results obtained during the first long range navigation test.