Before Elon Musk and Jeff Bezos can realize their goals of making Mars a final destination, most agree that a layover of sorts will be needed for the journey. This means buildings and infrastructure will need to be established, most likely, on the moon.
And while sending temporary solutions up in rockets is a short-term option, at some point permanent structures will be needed, which means building and digging into the moon’s surface. Designing equipment for moving lunar soil, called regolith, presents a couple of unique challenges.
On earth, excavators are heavy. This not only adds to their durability but enhances their ability to maintain better traction as they dig.
However, equipment weighing this much can be a problem in space, as everything needs to be transported by rockets. A heavier payload translates to larger rockets burning more fuel, which drives up costs and safety concerns.
Right now NASA has RASSOR, which is short for Regolith Advanced Surface Systems Operations Robot.
RASSOR currently uses spinning, hollow bucket drums on opposing ends to scoop up regolith. These drums use the weight from the material they’re collecting to improve their traction and balance while digging. RASSOR can then transport the regolith to a processing center valuable resources can be extracted and studied.
The rotating operation of the RASSOR, combined with the moon’s lower levels of gravity, means a lot of the regolith is lost during the excavation process.
This has led NASA to unveil the RASSOR Bucket Drum Design Challenge. The goal is to find a better bucket drum design that not only maintains the lower weight requirements, but also hits the operational goal of the bucket’s interior being at least half full before needing to be unloaded.
GrabCAD, a website for posting 3D models, will serve as the portal for submitting original designs. Entries will be judged on width of the scoops, volume of regolith captured, practicality of the design, and bucket drum mass, diameter and length.
The challenge is funded by NASA's Lunar Surface Innovation Initiative with a total of $7,000 to be awarded for the top five submissions.