Permanent tires can go on all terrains, can withstand cold temperatures of -200 degrees Celsius

Not just for Mars missions, this type of tire will likely be used on Earth as well.

The harsh Martian environment is eating away at the tires of the Curiosity rover – the one-ton, nuclear-powered robotic system tasked with exploring the strange new red soil – at a dizzying pace. After just one year of traveling at a speed of just 0.14 m/h – 0.04 m/s, Martian rocks have punctured large holes in Curiosity’s tires.

NASA has been working on ways to prevent this from happening in the future: they're redesigning the tire, so that by the time we reach Mars, we'll have a durable tire to ride on.

The tire is made of woven metal wire.

They created a virtually permanent tire, made from woven metal fibers that can "remember" their optimal shape and return to it after being distorted or deformed by external factors.

The research and design of this special tire was conducted at NASA Glenn Research Center in Cleveland, Ohio. Engineer Colin Creager and his colleagues woven metal – steel springs to create the tire. It has the ability to grip soft soil and sand very well, and can withstand a lot of weight. However, there is another problem.

“We only had one problem, these tires always dented after a while,” said engineer Creager.

Dented metal will have a hard time returning to its original shape.

Then he met Santo Padula, a materials scientist, who advised Creager to use shape-memory alloys – super-elastic metals that can return to their original shape after being deformed.

"From that point on, we began collaborating ... to create a new tire that we think will revolutionize tires for other planetary exploration vehicles and even innovate tires here on Earth," Creager enthuses.

Driving a car in space is as difficult as launching a spacecraft there.

NASA has been researching and developing tires suitable for traveling on other planets since the 1960s, when the Lunar Space Program began. First, it was the Lunar Roving Vehicle (LRV), used in the three Apollo missions 16, 16 and 17. Hard metal plates helped the tires move easily on the lunar surface, which consisted of lunar dust and small rocks.

Astronauts driving on the Moon.

But the surface of Mars is much more complicated. For a vehicle to travel there, it must satisfy a long and complicated list of requirements:

The tire must be able to travel on all terrain: the surface of Mars is sand, gravel and boulders, small and sharp gravel. The vehicle must be light: it costs 30,000 USD to land nearly half a kilogram on the surface of Mars, the lighter the vehicle, the less expensive it is. The usage time must be long: solar energy, nuclear energy will be what helps the vehicle maintain operation for many years, even decades. Can withstand erratic weather: normal rubber tires will not be able to survive in an environment without air, the temperature fluctuates from -129 degrees Celsius to 21 degrees Celsius in a short time.

On Curiosity is a 50cm high tire system, made of aluminum and reinforced with hard metal rings both outside and inside, the tire surface has V-shaped grooves for better grip, the spoke shock absorber system will help the vehicle resist strong shocks.

Just one year into its Mars mission, Curiosity's tires have developed worrying punctures.

But just a year into Curiosity’s Mars mission, its tires were showing worrying punctures. Today, the rover steers clear of small gravel to minimize damage, but the tires continue to deteriorate over time.

A new tire appears

After years of research, the team decided to use an alloy of nickel and titanium (NiTi). A spring made from steel can only be stretched by 0.3% (the distance between atoms in the metal changes) before it becomes permanently dented, unable to return to its original shape.

However, NiTi alloy can be stretched by 10% and still return to its original shape – it is up to 30 times more elastic than steel springs.

NiTi alloy can be stretched 10% and still return to its original shape.

Research results show that this new tire can carry more than 10 times the weight that Curiosity tires can carry, operate in temperature ranges from -130 degrees Celsius to 90 degrees Celsius, grip rocks and sand better, and climb slopes 23% better.

In the most extreme test, on a 10km road with a lot of "difficult" terrain, this tire still performed excellently. Currently, NASA is building a cold chamber to test tires in low temperature conditions.

Long road ahead

In a few years, NASA will launch the Mars 2020 rover – similar to Curiosity but heavier. Sadly, Creager says, the tire may not be suitable for Mars 2020 due to the tight schedule. The tire has a lot of testing to do, and the launch deadline is fast approaching.

The good news for us on Earth is that this type of tire could be applied right on the surface of our planet: the research team is collaborating with Goodyear – an American tire company founded in 1898 – to apply the above tire to dirt-road vehicles.

Initially, it will likely be used on military vehicles that travel on rough, rugged dirt roads. Creager hopes that this advanced tire technology can eventually be applied to road vehicles as well.

According to Khoahoc.tv