MIT engineers have designed a levitating space rover. This new vehicle could enable the exploration of parts of the Moon that are too treacherous for today’s rolling rovers. Rovers are hugely important for space exploration. They give us a way to study the surface of the Moon, Mars and asteroids up close without sending astronauts.
The problem with existing rovers, though, is that they rely on wheels to get around. That means that they can breakdown navigating uneven terrain. This limits the areas that we can explore because wheels breakdown or get jammed easily.
MIT engineers have now developed a space rover designed to levitate above the surface of the Moon, asteroids, or other airless bodies rather than roll directly across it. Paulo Lozano is director of MIT’s Space Propulsion Lab. He said that “With a levitating rover, you don’t have to worry about wheels or moving parts. An asteroid’s terrain could be totally uneven and as long as you had a controlled mechanism to keep your rover floating, then you could go over very rough, unexplored terrain, without having to dodge the asteroid physically.”
The Moon and asteroids are airless bodies. Because they are exposed directly to the sun, they can build up an electric charge. On the Moon, this charge is strong enough to levitate dust several feet above the surface. However, this charge would not be sufficient to levitate something as heavy as a conventional space rover. The lunar gravity would keep it on the ground. However, the MIT team decided that they could get around this obstacle by equipping the bottom of a saucer-shaped rover with tiny ion thrusters.
By using these thrusters to beam positively charged particles at the ground, they calculated that they could increase the electric charge pushing up against the rover. This should be sufficient to cause it to levitate. They built a small prototype and tested it in their lab.
Based on their tests, the engineers determined that it would be possible to levitate a space rover that weighed two pounds on Earth about one centimeter above the surface of the Moon with a fifty-kilovolt source of electricity. The same levitation could be caused by a ten-kilovolt charge on an asteroid.
Lorenzo said that “This kind of ionic design uses very little power to generate a lot of voltage. The power needed is so small, you could do this almost for free. In principle, with better modeling, we could levitate to much higher heights.”
The two-pound weight limit means that the levitating space rover would not be able carry as many instruments as a ground-based. However, the researchers intend their tiny rovers to work in fleets. Oliver Jia-Richards is the lead author of the MIT report. She said, “The idea is that you launch multiple of them.”
There is no plan to actually test the MIT levitating space rover on the Moon at this point. However, it is not the only option for overcoming the problem of rough extraterrestrial terrain.
Japan plans to launch a spherical rover that could roll itself over the Moon’s surface this year. The U.K. startup Spacebit is developing a spider-like rover to walk across the lunar surface.
NASA’s Ingenuity helicopter has already shown that robots can fly across the surface of other planets which have atmospheres. Someday, dexterous robot dogs may be sent to explore underground tunnels on Mars that are too treacherous for wheeled rovers.