As NASA points out, most of its robots come equipped with expensive, fancy machinery and instruments. However, with its sights set on interplanetary mining, NASA has decided to dispense with the expensive scientific equipment, and equip a robot with sturdy digging tools.Dubbed the RASSOR (pronounced “razor”), the prototype can’t be put up into space just yet, but NASA engineers already tackled the problem of the robot’s weight and stability. The unit needs to be light enough to fit on the vessel traveling through space, but heavy enough to remain operational once it is on a potentially lower gravity environment. So, the engineers gave the robot two digging drums on either end of the body that rotate in opposite directions; while one is digging, the other is rotating in the opposite direction, providing stability for the crawler. The diggers operate not by scooping up large amounts of soil at once like a big shovel, but by scraping little bits of soil at a time, which also helps with the machine’s stability.In order to test the diggers, the engineers built a harness that mitigated some of the unit’s weight in order to simulate the lower gravity of the Moon. Because of the two digger arms, the RASSOR is capable of complex maneuvers, such as pulling itself up over an obstacle or flipping itself over.The RASSOR is projected to weigh around 100 pounds, and be about the size of the Phoenix lander NASA sent to Mars. When the diggers are raised, the entire unit measures in at about 2.5 feet tall. The robot should be able to drive up to four centimeters per second, which is five times faster than the Curiosity rover.As for the RASSOR’s destiny, NASA envisions the robot skimming soil and putting it into a separate device that would extract ice and water, and use the chemicals within to produce fuel or breathable air. However, in order to gather enough resources to feed the machine that creates sustaining materials, RASSOR would need to be operational for 16 hours a day for five years straight.Almost amusingly, after figuring out the weight issue and creating satisfactory diggers, the tracks of the robot are actually the current problem — pebbles and sand sometimes get caught in between the tracks and makes the rubber grips slip off. At the moment, engineers are debating whether or not to dispense with the tracks entirely and switch to wheels.The team is already working on RASSOR 2, a prototype that is reportedly closer to the final envisioned digger that NASA aims to create.