Recently we've seen preliminary asteroid mining plans from Planetary Resources and Deep Space Industries, but what about NASA? The government agency would like to do some excavating on the Moon, Mars, and asteroids, too – but it isn't in it for the profit. NASA wants to clear the way for construction projects and mine materials for use by astronauts, and is developing a teleoperated robot called the Regolith Advanced Surface Systems Operations Robot (RASSOR, pronounced "razor") to get the job done.
According to NASA, it currently costs about US$4,000 to send a single pound (0.45-kg) payload into space, so keeping RASSOR's weight down is important. Unfortunately for an excavator, the lighter it is the more difficult its job becomes. Since RASSOR weighs just 100 pounds (45-kg), it relies on two opposing arms outfitted with counter-rotating bucket drums to provide the necessary counteracting force.
The drums scoop at 20 rotations per minute, trimming the top layer of soil to avoid jamming in the dense regolith at lower depths. Once it has collected about 40 pounds (18-kg) of material, the robot returns to a dump site where it can stand up on its tank treads in a Z-formation to deliver it to a production platform for processing.
"Producing water and fuel from the lunar soil would save the tremendous expense of launching the supplies from Earth, since 90 percent of a rocket’s mass normally consists of propellant, which can be made on the moon," said NASA.
RASSOR can also overcome rough terrain and even boulders by propping itself up on its arms. Should the robot accidentally flip over at any time, it can continue as if nothing happened thanks to its symmetrical design. During most operations, the robot would be wirelessly teleoperated by a human, who would view the robot's surroundings through its onboard camera. It could also be programmed to do certain jobs all on its own.
Future plans
NASA says it is already working on the next generation of the robot, and is looking at replacing the tank treads with wheels due to problems encountered during testing. The second prototype should be completed and ready for testing next year, but it will likely be several more years before it is sent into space.
It's possible that the completed robot will be sent to Mars, where it would most likely collect ice believed to exist at the poles. However, NASA admits that it would take a single robot five years, working 16 hours a day, to generate usable amounts of resources.