Nasa will use chainmail tyres on future rovers

Whether it’s on Earth or on Mars, exploration of any terrain requires mobility – which for most vehicles means good tyres.

In the hope of avoiding a flat tyre during explorations of alien planets, Nasa has developed a chainmail tyre.

The innovative design is made up a weave of titanium nickel, an alloy that remembers its original shape after it has rolled over something, removing the risk of dents.

The tyre has been developed by experts at Nasa’s Glenn Research Centre in Cleaveland, Ohio.

The idea was first conceived in the mid-2000s, when Vivake Asnani, a Nasa engineer, worked with Goodyear to develop the Spring Tyre – an airless tyre that consists of several hundred coiled steel wires woven into a flexible mesh.

The Spring Tyre was found to generate very good traction and durability in soft sand and on rocks, and the design was fitted on the Mars Curiosity Rover, which is currently on Mars.

But in 2013, a year after the rover landed on Mars, engineers began to notice significant wheel damage, due to the unexpectedly harsh terrain.

This caused concern about the ability of the rover to drive far enough to complete its intended mission.

Now, Colin Creager and Santo Padula, Nasa engineers, have come up with a solution to this issue – a new material.

Mr Padula said: ‘The material that it’s made from is an alloy based on titanium.

‘This particular material doesn’t deform like conventional materials.

The material that it’s made from is an alloy based on titanium. This particular material doesn’t deform like conventional materials

‘In those materials, when we put stress on them, we basically are stretching the bonds between the atomic structures.

‘But this material has a unique characteristic that allows it to do an atomic rearrangement to accommodate deformation.

‘That lets us do about 30 times the deformation we could do in a conventional material, without having permanent deformation happening.

In most materials, when we put stress on them, we basically are stretching the bonds between the atomic structures. But this material has a unique characteristic that allows it to do an atomic rearrangement to accommodate deformation

Mr Padula said: ‘We could actually deform [the tyre] all the way down to the axle and have it return to shape – something that we couldn’t even contemplate in a conventional material’

‘We could actually deform [the tyre] all the way down to the axle and have it return to shape – something that we couldn’t even contemplate in a conventional material.’

After building the shape memory alloy tyre, the researchers sent it to Nasa’s Jet Propulsion Laboratory’s Mars Life Test Facility, where it performed impressively on the punishing track.

Nasa highlights three key benefits to developing tyres that can perform on Mars.

Firstly, they would allow rovers to explore greater regions of the surface than currently possible.

Secondly, because they conform to the terrain and do not sink as much as rigid wheels, they can carry heavier payloads for the same given mass and volume.

And finally, because the tyres can absorb energy from impacts at moderate to high speeds, they can be used on crewed exploration vehicles which are expected to move at speeds significantly higher than the current Mars rovers.

It is unclear when Nasa plans to start using the tyres.

The shape-shifting tyres would allow rovers to explore greater regions of the surface than currently possible

After building the shape memory alloy tyre, the researchers sent it to the Jet Propulsion Laboratory’s Mars Life Test Facility, where it performed impressively on the punishing track