Sporty little number: The distinctive Mecanum roller-wheel design has already been proven in applications such as advanced forklifts and wheelchairs. Image: Architecture and Vision

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It's a still sunrise over a flat, rusty Martian plain. On the horizon, a strange cloud of dust is kicked up through the thin gravity. It can be traced back to a gleaming vehicle, shaped like a beetle, tracking the desert on conspicuously oversized wheels. The three astronauts onboard are just brewing their morning coffee, having slept through the Martian night while the rover drove on autopilot toward the rim of Victoria Crater.

The Mars car of the future will feature German engineering, naturally. At least that's the view of Architecture and Vision, a small multinational design collaboration with one office based in Munich. Andreas Vogler and his Rome-based partner Arturo Vittori recently put the finishing touches on MarsCruiserOne, a conceptual design of a three- to four-person rover for a possible future manned exploration of the Red Planet.

Making the most of the limited available space inside such a vehicle is the ultimate design challenge, says Vogler. "You really think about resources because they are at a minimum.

In having to consider these extreme situations – both environmental and psychological – you learn what design can and can't do," he says. "Can you imagine living for two years in a little tin box?"

When the astronauts finally strap in, the MarsCruiserOne needs to be a comfortable, efficient, smooth and trouble-free ride. To this end, interiors in the pressurised cabin are modular and multi-purpose, with storage spaces made of firm but flexible textiles. Then there's the turning circle: the rover can turn a full 360 degrees on the spot. It can also drive diagonally and manoeuvre to dock with a base unit or other rovers side-to-side.

The idea for the design started on a flight from Bremen to Munich six years ago, the first drafts scrawled on the sketchpad of aerospace consultant Stephen Ransom. The challenge was how to fit the rover in the Ariane launch vehicle, with a diameter of only five metres.

"I started to look at ways to fold the wheels up so you could get better packaging within the rocket fairing," Ransom says. "I thought, 'Why does it need to be so complicated? Why not make the wheels much bigger and put the cabin between them?'"

Doing so opens up a lot more space for the astronauts, gives the rover a symmetry that is helpful for the rocket launch and moves the centre of gravity closer to the surface, which also serves to make the vehicle more stable.

Home away from home: The vehicle is envisaged to provide life support for up to 20 days for its occupants.

Over the years Ransom continued to develop his rover ideas and began collaborating with Vogler and Arturo Vittori, whose brother happens to be an astronaut. Doing research on big wheels led to the idea of getting rid of the traditional axle-and-hub power-train altogether.

Instead they opted for linear motors, like those used on maglev (magnetic levitation) trains to create drive power in a rotating ring, which forms the rim of the wheel. Losing the wheel hub also meant gaining four new spaces, which allowed the airlocks and docking hatches to be placed in the side of the cruiser.

Putting rollers at 45-degree angles on the wheel rim – thus making a so-called Mecanum wheel – makes the cruiser omnidirectional, Vogler says. The ride is smoothed with the kind of electronic (as opposed to hydraulic) active suspension that was introduced in Formula One cars in the 1990s.

"It looks pretty sporty!" exclaims Hoppy Price, a systems engineer at U.S. space agency NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. He says the agency has considered several concepts for manned Mars rovers, but as yet there's no baseline design.

Even so, the creators of MarsCruiserOne are part of a vigorous and growing community of ad hoc space architects and design engineers who are capturing imaginations and grappling with concepts at the grassroots –concepts that contractors and space agencies keep their eyes on.

NASA's Brent Sherwood, also at the JPL, is currently editing a collection of space design concepts, and he has seen the proposals for MarsCruiserOne. "I'm worried about it tipping over," he says. "But it is very cool – one of the more advanced designs I've seen."

Marc Cohen, an engineer who is currently working on mobile lunar bases at NASA's Ames research facility in Mountain View, California, is less enthusiastic. "There are a lot of pretty pictures of the Mars Cruiser," he says, "but the design integrity is not apparent. They don't seem to have a well-defined or well-structured Mars or lunar surface mission that establishes requirements that would lead to this particular design."

It may well be a while before the cruiser makes it to Victoria Crater, but JPL's Sherwood wants the designs to keep on coming.

"Most people need imagery and concepts so they can see how things might actually be," he says. "And exciting design options put out by individual, sometimes brilliant, designers – can set expectations that ultimately help to keep government-funded projects from becoming pedestrian."