NASA’s RASSOR (Regolith Advanced Surface Systems Operations Robot) was recently tested on simulated lunar soil at Kennedy Space Center’s Granular Mechanics and Regolith Operations LabThe excavator is built to dig and haul Moon-like regolith, preparing technology for sustained lunar missions. On May 27, NASA mechanical engineer Ben Burdess observed RASSOR’s counterrotating bucket drums churn through the soil simulant and carve a three-foot berm. This trial focuses on RASSOR’s digging drums and directly informs development of NASA’s next-generation Moon-mining excavator, the In-Situ Resource Utilization Pilot Excavator (IPEx)
RASSOR’s Counterrotating Drums and Regolith Excavation
According to NASA’s official website, each of RASSOR’s arms carries a bucket drum that spins in the opposite direction of its mate. Engineers note that this opposing rotation gives RASSOR extra traction even in weak gravity. In the Kennedy lab test, those counterrotating drums anchored the robot into the simulant and effectively dug soil – proof that RASSOR can grip and move regolith reliably on the Moon. With that traction, RASSOR can dig, load, haul and dump loose soil.
The collected regolith can then be processed into hydrogen, oxygen and water, resources critical to sustaining astronauts on the Moon. In short, the test showed RASSOR effectively excavating lunar soil simulant while its drum design demonstrated how future machines can operate in the Moon’s low gravity.
Toward the Moon with IPEx Excavator
NASA engineers say this RASSOR test was primarily to check the bucket-drum design slated for the In-Situ Resource Utilization Pilot Excavator (IPEx). RASSOR serves as a prototype for IPEx, which will be far more autonomous and capable.
IPEx is engineered as a combined bulldozer and dump-truck robot that can mine and transport large volumes of lunar soil. Ultimately, IPEx will dig up regolith and feed it into on-site processing units to extract oxygen, water and fuel from the Moon’s soil. Using these local resources is a cornerstone of NASA’s strategy for supporting a sustained human presence on the Moon and eventually Mars.