Audi
Audi Lunar Quattro
The Audi Lunar Quattro rover has been fully developed and plan to set off in late 2017 with a launcher booked with Spaceflight Inc.
Global car manufacturer, Audi is set to launch a lunar rover made with weight-saving 3D-printed aluminium parts by the end of next year.
Partnering with a space travel group called Part-Time Scientists, Audi have entered the Google Lunar XPRIZE competition. Working together since 2015, the goal is to send the co-developed rover to the moon and complete a set of required tasks. Today, they announced the Audi Lunar Quattro rover has been fully developed and plan to set off in late 2017 with a launcher booked with Spaceflight Inc.
Audi have highlighted 3D printing, specifically, as a particularly helpful technique in the construction of the Lunar Quattro. In this case, the wheels of the rover were made with the aid of 3D printing, reducing down time and saving weight.
“3D printing with aluminium makes it possible to produce lightweight parts of almost any shape with a closed shell,” said Harald Eibisch, an engineer in casting and additive manufacturing technology development at Audi. “The wheel of the Audi Lunar Quattro has a wall thickness of only a millimetre but displays outstanding strength thanks to its sophisticated design. The material has also been thoroughly tested in the Audi laboratories. We’ve been using alloy AlSi10MgSr in the aluminium castings of our Spaceframe bodies for decades.”
Audi
Audi Lunar Quattro wheel
32 hours and 20 minutes is the time it takes for the 3D printer to produce one of the Audi lunar quattro’s four wheels.
The weight saving achieved by Audi in the Part Time Scientists’ Audi Lunar Quattro rover comes to around 1.6 kilograms for the four wheels alone. Typically, a kilogram of scientific payload in a rover of this kind is worth the equivalent of €800,000. Thanks to the weight saved using additive manufacturing techniques, the team have been able to load the vehicle with additional scientific material worth around €1.28m.
Additionally, the moon rover’s suspension, wheel drive housings, swings arms and camera head were also improved upon. But it was the wheels in particular where a huge advancement was made within a short space of time. First, Audi designers revamped the open spoke wheel of the Part Time Scientist’s Asimov Rover and turned it into a closed system, making it less vulnerable to moon dust. They also increased its size by 22%. The greater contact area brings improved climbing capability in fine-grained moon sand dunes.
Then, Audi engineers developed an enhanced design of the wheel, originally made up of several machined aluminium parts and tweaked the profile of the treads for better grip.
The decisive step in preventing any weight gain was the use of 3D printing technology.
“In 3D printing, we convert design data files into a buildable format,” Eibisch added. “We just take the shape of the part’s outer shell and add a millimetre of material. This results in a complex and stable surface on the inside that even the best CAD programme can’t achieve. The entire wheel has a wall thickness of only one millimetre. That way we’ve been able to reduce the weight per wheel by 400 grams.”
The challenge now is to safely land the lunar rover on the moon’s surface, travel at least 500 metres and transmit HD images back to Earth. Audi’s Lunar Quattro boasts four cameras to take 360-degree photos. Similar to most Earth-bound Audis, the Lunar Quattro is all-wheel drive, thanks to electric motors in all of its wheels. Unlike most Earth-bound Audis, the top speed is a lowly 2.2mph.
Before the rover can be let loose on the moon, more testing needs to be carried out, including stress testing of the Audi rovers and the lander. The entire mission will also be simulated in the Middle East to explore any faults.
