South Korean Engineers Design Shape-Shifting Wheels to Unlock the Moon's Hidden Caves
Finn's Take· TL;DR- Shape-shifting wheels compress from 20 to 9 inches, enabling lunar rovers to fit in landers while gaining superior climbing ability once deployed.
- Origami-inspired design using flexible steel strips mimics Da Vinci bridges, eliminating hinges to resist cold welding and dust damage in extreme lunar conditions.
- Team plans autonomous rover using reinforcement learning; South Korea's 2027 space budget increased 47% to $1.2 billion, backing future lunar exploration missions.
A Wheel That Thinks Like Origami
A collaborative research team from the Korea Advanced Institute of Science and Technology (KAIST) and the Unmanned Exploration Laboratory has developed an innovative wheel that can effectively navigate the Moon's most challenging terrains — including steep lunar pits and lava tubes. The breakthrough centers on a unique "origami-inspired" deployable airless wheel that can greatly increase its diameter to overcome obstacles that would stop conventional rovers cold.
The design, developed over three years by PhD candidate Seong-bin Lee and Professor Dae-Young Lee, uses interwoven flexible strips of high-carbon steel to create a deployable, airless wheel. Its structure mimics a Da Vinci bridge — a self-supporting system held together by gravity and friction — combined with origami's shape-changing ability. The result is a wheel that transforms without a single traditional mechanical hinge, a detail that matters enormously in the hostile environment of space.
By utilizing a specialized elastic metal frame and fabric tensioners instead of traditional hinges, the design ensures reliable operation in the harsh lunar environment, effectively resisting the risks of cold welding and mechanical failure caused by fine dust. On Earth, that might sound like an engineering footnote. On the Moon, it could be the difference between a successful mission and a stranded rover.
The Numbers Behind the Design
The design allows the wheels to shrink from 20 inches to 9 inches in diameter, fitting inside a lunar lander, then expand to traverse the Moon's surface. That kind of compressibility is crucial — every cubic inch of space inside a lander is precious, and bulky fixed wheels have long been a logistical headache for mission planners.
A small rover equipped with these wheels maintains a low profile during transport but gains the climbing ability of a much larger vehicle once deployed on the lunar surface. Fabricated from heat-resistant high-carbon steel, the fire-proof wheels are designed to bend and flex while withstanding the Moon's extreme temperature swings of more than 500° Fahrenheit. That thermal resilience is non-negotiable — the Moon's surface can roast or freeze equipment with little warning.
The team rigorously tested the wheel's capabilities using artificial lunar soil. The wheel demonstrated superior traction on loose slopes and proved its structural integrity by withstanding a drop impact equivalent to a 100-meter fall in lunar gravity. Those are not gentle benchmarks.
Why Lava Tubes Matter So Much
Lunar lava tubes and pits are prime candidates for future human habitats due to their natural shielding from cosmic radiation and extreme temperature fluctuations, but accessing them is perilous. These underground tunnels, formed by ancient volcanic activity, represent one of the most scientifically compelling — and physically treacherous — destinations on the Moon.
Researchers evaluated scaled-down versions in laboratory settings under extreme temperatures, in mud, and on simulated lunar regolith. To prepare, the team also tested prototype hardware inside caves and lava tubes on the South Korean island of Jeju. It's a clever workaround — Jeju's volcanic geology offers one of the closest natural analogs to lunar cave environments available on Earth.
What Comes Next
The team now plans to build an autonomous rover. KAIST master's student Isop Yoon is using reinforcement learning — a type of machine learning — to optimize the design and train the vehicle to move. The algorithm should help determine the robot's shape and the number of wheels it needs to overcome obstacles on the lunar surface.
The project is among those at KAIST funded by the Korea Aerospace Administration. South Korea's draft budget for 2027 proposes a record 1.65 trillion won — about $1.2 billion — for the space sector, which is 47% more than the amount allocated in the 2026 budget. That financial commitment signals that this isn't a research curiosity — it's a national priority.
If testing and further development are successful, the collapsible wheels could make it possible to stow the rover compactly inside a lander and deploy it on the lunar surface — and potentially into the Moon's most mysterious underground spaces. The ancient art of paper folding, it turns out, may be one of humanity's most powerful tools for reaching places no machine has ever gone.