Swiss wheels for upcoming Moon missions

In mid-2027, two astronauts from NASA’s Artemis III programme are expected to set foot on the Moon for the first time in over 50 years – since the Apollo 17 mission. In addition to NASA, the European Space Agency (ESA) also plans to send European astronauts to the Moon, as part of its Terrae Novae 2030+ roadmap. The long-term goal: to establish a permanent human presence on the Moon from 2030 onward.

The Lunar Terrain Vehicle – more commonly known as the lunar rover – is critical for future lunar exploration. One of its most vital components, the wheel, is currently being developed near Fribourg, Switzerland by Venturi Space. This innovation will ensure that the FLEX Rover, built by US-based partner company Astrolab, is not only fast and agile but also resilient enough to handle the Moon’s extreme environment.

That’s no easy task. The Moon presents harsh and unforgiving conditions. Temperatures swing dramatically from –240°C to +130°C. Without an atmosphere, the lunar surface is exposed to cosmic radiation, further stressing the rover. Until now, no material has existed that could repeatedly deform and return to its original shape across such a wide temperature range. To raise the bar even further, NASA has specified that the lunar rover must be able to travel 5,000 kilometres. For perspective, the rover used in Apollo 17 covered just 35.9 kilometres.

The wheel developed by the Swiss company may be a game-changer. Designed by a multidisciplinary team of engineers, chemists, and physicists, the wheel is hyper-deformable, meaning it can flex and adapt to uneven terrain while remaining tough and durable.

Thanks to its flexible design, the wheel can climb gradients steeper than 20 degrees – far outperforming rigid wheels, which typically struggle with slopes over 8 degrees. A total of 192 cables act like spokes, connecting the inner wheel structure, while 96 springs give it its remarkable deformability. The tread consists of several relatively inextensible stainless steel blades, held in place by a novel, superelastic material.

Performance testing is under way at a test site in Payerne. A custom-built thermal chamber simulates the Moon’s vacuum and temperature extremes, while a mechanical system tests the wheel's durability over simulated long-distance travel.

A small version of the rover featuring the Swiss wheels will be tested on an unmanned lunar mission aboard the Lunar Lander GRIFFIN-1 as early as late 2025. One year later, a SpaceX rocket is scheduled to deliver the FLEX Rover to the Moon’s South Pole. It will be remotely operated from Earth to carry out scientific experiments and commercial tasks. Two astronauts in spacesuits will also be able to board and drive it across the lunar surface.

While it is not yet certain whether this rover – and with it the Swiss-developed wheels – will be selected by NASA for all future Moon missions, signs point to a promising and ‘smooth’ journey on the Moon.