NASA tested five preliminary wheel designs for lunar exploration vehicles on July 31, 2026, during the final phase of the Rock and Roll with NASA challenge, which attracted 128 entries from 49 countries. The tests were conducted at the rock yard of NASA’s Johnson Space Center in Houston, using the MicroChariot test vehicle, which weighs 45 kilograms.
The challenge was part of NASA’s effort to develop mobility capabilities on the lunar surface as it prepares to establish a lunar base and expand the scope of work performed by crews and robotic systems. The agency focused on lightweight, durable, scalable wheels capable of absorbing impacts, maintaining traction at higher speeds, and withstanding the harsh lunar environment.
Different Designs for One Problem
The five prototypes revealed different engineering approaches rather than relying on a single standardized design. Hellenic Technology of Robotics SA developed the HTR Variable Flex Lunar Wheel, featuring an internal system that changes the wheel’s stiffness according to the terrain and the vehicle’s needs, based on technology the company had been developing for terrestrial wheels for about ten years.
Hyperbola’s Hiper Wheel uses tensioned cables and a corrugated structure that give it spring-like behavior, allowing it to flex without conventional radial spokes. Huff Helo Inc. presented the Huff Helo Flexible Titanium Wheel, made from formed titanium sheets that serve as both the structure and the spring. However, its high stiffness caused it to bounce over some obstacles rather than fully adapt to the ground surface.
Deborah and Craig Payne designed the Payne Aviation Wheel, drawing on ideas inspired by aviation and early automobile tire designs, combining a pneumatic approach with historical wheel-making principles.
The Winning Design
The Scotch Pad Tyres team, founded by Australian mechanical engineer Daniel Bloomfield and his son Isaac Bloomfield, won. The prototype relies on a tire structure made from a Nomex-based material supported around an aluminum hub. The tire’s soft material allows it to deform around the terrain, while internal supports help maintain its shape. An outer surface treated with a mixture of epoxy and corundum grains was also added to improve traction.
Why Does This Test Matter?
The tests showed that wheel performance cannot be separated from the nature of the surface. Loose materials may reduce traction, while rocks and slopes impose different requirements related to stability. Therefore, lunar vehicles will not necessarily need the same wheel; priorities will vary among speed, payload capacity, durability, and the ability to traverse specific types of terrain.
NASA uses ground-based prototypes to study mobility technologies, while lunar mobility vehicles are scheduled to be delivered to the surface through the Commercial Lunar Payload Services initiative. Winning one of the designs does not mean it will be adopted directly for a lunar mission; rather, it gives engineers options and technologies that can be developed later.
Possible Next Steps
NASA may test the wheels in the thermal-vacuum chambers at Johnson Space Center to simulate lunar dust, vacuum, and extreme temperatures. They could also be evaluated over longer distances and with different sizes and loads. The challenge was conducted by the Johnson Robotics Project and managed by NASA’s Center of Excellence for Collaborative Innovation, part of the agency’s Prizes, Challenges, and Crowdsourcing program, with support from students from the NASA Robotics Academy and engineers from Glenn Research Center. HeroX managed the challenge on behalf of the agency.