In the mid-1960s, before anything had soft-landed on the Moon but well into Apollo’s development towards the lunar landing, NASA engineers started figuring out what a roving vehicle for extended surface exploration might look like. As engineers are wont to do, a team looked to nature for inspiration and found an unlikely muse in the mighty worm and centipede.
Learning the Moon
In the early days of the space age, no one knew what the lunar environment was like, and that was a problem when it came to planning for astronauts to land on and explore the surface. Planners only knew the basics — that the Moon’s environment includes reduced gravity, a vacuum, extreme temperatures, and hazards like radiation and meteorites. But the surface itself was a mystery. No one knew whether the regolith was a thin layer or so thick it would be impossible to land without being buried in the dust. Or whether the surface would be strong enough to wear the weight of a rover like a traditional, Earth-like car, or even the lunar lander. The texture of regolith was another potential problem; it might be too hard to walk on. Some even wondered if the surface would be so uneven that no lunar rover would be able to traverse the surface.
This last point became important when planning for extended surface operations. If a crew were able to land on the Moon, NASA would eventually want them to cover more ground to visit an array of locations on the surface, which would mean they would need some method of travel. There were flying systems and pressurized ATV-type vehicle options, but there was, at the time, the potential that none of them would work.
Considering the unknowns, guidelines soon emerged to shape a round of studies into surface vehicles. The safest bet was for a vehicle to have no external moving parts, removing the risk of regolith or rocks affecting the system. A low footprint pressure was ideal, spreading as much of the vehicle’s weight over as large a surface area as possible so it didn’t risk sinking into or breaking through the lunar surface. There was also interest in a vehicle that could bridge crevices in case it turned out the surface was too cratered for any traditional vehicle. NASA also needed something that could be folded up for easy transport to the lunar surface and unloaded without ground support. And as a…