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The more legs the better, right?!

That's what a team of researchers from Georgia Institute of Technology in the US decided to test.

They created a number of robots inspired by our leggy insect friends the centipede, that each have different amounts of legs to see which worked the best on difficult surfaces.

"When you see a scurrying centipede, you're basically seeing an animal that inhabits a world that is very different than our world of movement," said Daniel Goldman, a Physics professor at Georgia Tech who led the research.

"Our movement is largely dominated by inertia. If I swing my leg, I land on my foot and I move forward. But in the world of centipedes, if they stop wiggling their body parts and limbs, they basically stop moving instantly" he said.

Researcher Baxi Chong and his colleagues built a series of robots using a 3D-printer, ranging from 6-16 legs.

Each segment of the robot's body had two legs and multiple motors.

The robots didn't have any sensors or cameras, so they couldn't see their environment, and moved in a pre-programmed way similar to that of a real-life centipede.

The researchers then built a range of indoor and outdoor obstacle courses to test the centipede robots movement capabilities on, and record their findings after a few runs.

From looking at the results, the researchers found that the robots with fewer legs showed lots of variation in how long they took to move between two points, with some trials taking twice as long as the others.

Robots with 14 and 16 legs made it through the obstacle courses faster, and more consistently than the others.

Using maths the team found that robots with more than 10 legs could cover a 60cm distance faster and more reliably than those with fewer legs.

"Many robots could probably make it from some point A to point B, but it's hard to prove with certainty that they'll do that without taking a ton of time.

"Here, when we increased the number of legs, we saw, and could even mathematically prove, that they'll for sure make it," says Daniel Goldman.

Baxi Chong says that this could be because lots of legs repeating many steps breaks up the robot's movement, so the robot wastes less energy on overcoming difficult surfaces.

The researchers think that robots like this could be used to bring aid to areas hit by disasters like earthquakes where the ground is tricky to travel across.

They also think the tech could be used on farms to help keep an eye on pesky weeds, but they say it needs more testing.