Robotics engineers often find their inspiration from nature. For six-legged robots, a nature-inspired gait proved an impediment to maximum speed.

Researchers at the University of Lausanne and Swiss Federal Institute of Technology, UNIL and EPFL, wanted to find out if there was a faster way for their insect-inspired robot to scurry.

Most insects walk with a tripod gait, keeping three legs in contact with the ground at all times.

"We wanted to determine why insects use a tripod gait and identify whether it is, indeed, the fastest way for six-legged animals and robots to walk," researcher Pavan Ramdya said in a news release.

Using the fly species Drosophila melanogaster as a model, researchers built a computer simulation to test different gaits. The computer simulation employed an evolutionary-like algorithm, designed to generate gait patterns and test for optimum performance.

The model showed the traditional tripod gait is most effective for an insect climbing a wall. However, the gait requires adhesive pads for the feet, an attribute robots don't have. For a basic floor walk with no adhesive booties, the algorithm determined a bipod gait, with only two feet on the floor, was faster and more efficient.

Researchers published their findings in the journal Nature Communications.

"Our findings support the idea that insects use a tripod gait to most effectively walk on surfaces in three dimensions, and because their legs have adhesive properties. This confirms a long-standing biological hypothesis," said Ramdya. "Ground robots should therefore break free from only using the tripod gait."

When scientists raced two six-legged robots, each with a different gait, the bot sporting the bipod gait won.

Researchers also tested the gait of flies wearing tiny booties designed to negate the advantages of their adhesive pads. Flies with booties on their feet naturally adopted a bipod gait.

"This result shows that, unlike most robots, animals can adapt to find new ways of walking under new circumstances," said researcher Robin Thandiackal. "There is a natural dialogue between robotics and biology: Many robot designers are inspired by nature and biologists can use robots to better understand the behavior of animal species.