Texas A&M University researchers are refining an unusual lunar explorer: RoboBall III, a six-foot-wide inflatable sphere designed to move where traditional rovers struggle. In quarry tests in Texas, the 150-kilogram prototype rolled over rocks, gravel and soft ground without needing wheels or legs.
The concept is aimed at the Moon's steep, permanently shadowed craters near the south pole, where sunlight never reaches the surface. These regions, including areas around Shackleton crater, are of high scientific interest because they may preserve frozen water and other volatile materials.
RoboBall moves with an internal pendulum system that shifts its center of mass, allowing it to roll, steer and slow itself on slopes. Its sealed shell also helps protect the robot's mechanisms from lunar dust and rough terrain. According to the team, the current version can carry about 16 liters of instruments or sampling gear and has already shown the ability to climb slopes of roughly 20 degrees.
The project, led by Texas A&M's Robotics and Automation Design Lab, builds on an idea first developed by Robert Ambrose during his time at NASA. The latest trials also explored a sample-return concept in which a larger rover could deploy RoboBall into a crater and receive collected material back uphill in a small rocket-powered container.
While the robot still needs greater autonomy and space-rated hardware before it can face lunar extremes, the design points to a fresh way of thinking about exploration: using motion, shape and simplicity to reach places that are otherwise difficult to access. If successful, spherical robotics could broaden how future missions study the Moon and other rugged worlds.
