Hopping Robots Could Explore Moon Craters, Asteroids
This photo taken by NASA's Lunar Reconnaissance Orbiter (LRO) shows high sunlight reflecting off the moon's Aristarchus crater.
CREDIT: NASA/GSFC/Arizona State University
A robot that might serve as the prototype for future hopping rovers that can jump between deep craters on the moon or even land on asteroids has passed a preliminary zero-gravity test with flying colors, scientists have announced.
A space robot equipped with thrusters to make hops on the surface of a planet, moon or asteroid can cover much more ground than a traditional rover, explained Bobby Cohanim, technical director of the Google Lunar X Prize efforts at MIT’s Draper Laboratory.
The Google Lunar X Prize offers a purse of $20 million for the first privately funded vehicle to land on the surface of the moon, travel more than 500 meters across the surface, and send back HD images and video.
"Rovers are very good at doing neighborhood science and exploration," Cohanim said. "Hoppers can fly from one neighborhood to another."
Hoppers can also fly in and out of craters and are less likely to get stuck in soft surfaces, he added.
Recently, students at MIT tested a prototype of a hopper, called Terrestrial Artificial Lunar and Reduced Gravity Simulator, or TALARIS, during a NASA microgravity flight in the Zero-G Reduced Gravity Aircraft.
On solid ground, the TALARIShas thrusters powered by compressed nitrogen gas and four electric ducted fans (EDFs) that simulate the gravity on the moon. The latter are essentially "very small jet engines," said John Reynolds, a senior at MIT involved with the project. "They take off five-sixths of the weight, so when the thrusters fired, you'd get the realistic gravity [of being on the moon]."
But fans can only simulate so much, and the EDFs are also incredibly loud. "It fills the room and everything just echoes," Reynolds said. So the team set up a microgravity flight to test the prototype's navigation system.
Because of safety concerns, the students could not use a robot with thrusters, so two students tapped on discs mounted to the prototype to simulate its thrusters.
After the students acclimated to the ups and downs of the parabolic flight, "we accomplished several good hops and got good data," which will be used to refine TALARIS' navigation system, Reynolds said.
The same navigation system could be adapted to explore other low-G environments, like asteroids, Cohanim added. With an asteroid, the gravity is so low that the hopper is not so much "landing" as simply coming close to the rock's surface.
"The two systems are doing more of a rendezvous and docking kind of maneuver," he said.
The deadline for the Google Lunar X Prize is the end of 2015.