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Goodyear working on airless metal tires for GM’s Moon Buggy

July 20, 2022
Henry Club

GM ,GM, And good year ,GT, Have been to this dry, dusty land before. Both companies worked on NASA’s original lunar roving vehicles that went to the Moon in the early 1970s. GM (then working with Boeing instead of Lockheed Martin) And the three lunar rovers he built still sit on Goodyear tires made of wire mesh.

Tires made of rubber and filled with air like tires will not work on the Moon for some reason.

First, heavy temperatures drop from 260 degrees Fahrenheit in the day to -280 degrees at night, making tires full of air impossible. Air expands and contracts with changes in temperature, so it will be extremely difficult to keep an air-filled tire from flattening at night or bursting during the day.

Second, the Moon is bathed in intense radiation that degrades rubber because there is no atmosphere.

Never mind the fact that changing a flat tire on the Moon in rigid spacesuit gloves won’t be easy.

However, this time the challenges are even greater than 50 years ago. The original lunar rovers were, essentially, disposable. They were designed to work for a short period of time, leaving them as planned. The new rovers – which are as electric as the originals, since even internal combustion engines would not work on an airless Moon – can be recharged repeatedly so that they can operate for years.

Plans also call for them to operate autonomously so they can drive there and do things, even when people aren’t around. It also means that the rovers will be exposed to more extreme temperature changes for a longer period of time. One moon day and one moon night can be two weeks long. And, each sunrise and sunset, the temperature changes from extremely hot to extremely cold almost instantly.

Partner companies are talking about allowing not only NASA, but also private firms, organizations and international agencies to use them for projects on the Moon. Given the long operating life expected from these new tires – and the fact that it would be a very long wait for “roadside assistance” on the Moon – Goodyear is exploring new technologies.

The moon buggies from the 1970s are still there. GM and Lockheed Martin want to make new ones
Technically, the Lunar Rover will not have tires in the traditional sense. The wheels and tires will be one piece, as is the case with airless tires used on Earth. Goodyear uses airless rubber on experimental autonomous delivery vehicles where there is no driver to change tires. Michelin sells similar airless tires For mower and other equipment. They rely on rubber ribs, rather than air, to hold the outside moves. Goodyear’s Lunar tires may use springy metal ribs instead. Tread surfaces can also be made of metal, but it won’t have the typical solid blocky tread you see on terrestrial tires.

“It’s like an open weave or mesh with a variety of three-dimensional features,” said Michael Rachita, senior program manager for non-pneumatic tires at Goodyear.

Tires will need to use special metal alloys to withstand extreme temperature changes while maintaining flexibility and strength. Recreating the extreme cold of a lunar night is particularly challenging on Earth, as the air would become liquid at those temperatures. Kirk Shireman, Lockheed’s vice president of lunar exploration, said the test should be done in a vacuum.

The surface of the Moon is covered with ultra-abrasive sand. Since there is no wind or wind on the Moon, the sand particles do not move around and become smooth, so each particle has sharp points. There are companies that make artificial moon dust based on samples brought back by the Apollo missions of the 1960s and ’70s, Rachita said, so researchers at Goodyear are using it to test different tread patterns.

It can be glued to paper or board to make “moon sandpaper” to test abrasion resistance, he said.

GM, Goodyear and Lockheed Martin ,LMT, The Lunar rovers are already parked and waiting on the Moon before they are expected to send NASA astronauts in 2025. The companies hope to become the first to establish extended commercial vehicle operations on the surface of the Moon, they said in an announcement.