  In recent years, robotic exploration has become increasingly important in
planetary exploration. One area of particular interest for exploration is
Martian lava tubes, which have several distinct features of interest. First, it
is theorized that they contain more easily accessible resources such as water
ice, needed for in-situ utilization on Mars. Second, lava tubes of significant
size can provide radiation and impact shelter for possible future human
missions to Mars. Third, lava tubes may offer a protected and preserved view
into Mars' geological and possible biological past. However, exploration of
these lava tubes poses significant challenges due to their sheer size,
geometric complexity, uneven terrain, steep slopes, collapsed sections,
significant obstacles, and unstable surfaces. Such challenges may hinder
traditional wheeled rover exploration. To overcome these challenges, legged
robots and particularly jumping systems have been proposed as potential
solutions. Jumping legged robots utilize legs to both walk and jump. This
allows them to traverse uneven terrain and steep slopes more easily compared to
wheeled or tracked systems. In the context of Martian lava tube exploration,
jumping legged robots would be particularly useful due to their ability to jump
over big boulders, gaps, and obstacles, as well as to descend and climb steep
slopes. This would allow them to explore and map such caves, and possibly
collect samples from areas that may otherwise be inaccessible. This paper
presents the specifications, design, capabilities, and possible mission
profiles for state-of-the-art legged robots tailored to space exploration.
Additionally, it presents the design, capabilities, and possible mission
profiles of a new jumping legged robot for Martian lava tube exploration that
is being developed at the Norwegian University of Science and Technology.
