Robot gives clues on evolution of flight

Posted by Kate Taylor

A tiny robot insect has given support to the idea that the first flying creatures were tree-dwellers.

A six-legged, one-ounce robot has shown that while flapping wings help a creature run faster, it's unlikely that they could have given it enough speed to take off from the ground.

The flapping wings increased the speed of the running robot by 90 percent, going from 0.68 m/s to 1.29 m/s, and also enabled it to climb steeper gradients, increasing from a 5.6° ascent to a 16.9° ascent.

But, say the researchers from the University of California, Berkley and the Smithsonian Tropical Research Institute, this isn't enough to deliver what they had hoped - a hybrid running and flying robot with many civilian and military applications.

"On the current robot, the wings allow for a stable descent, meaning it can jump from high areas and stably land on its legs at the bottom," says Kevin Peterson, lead author of the study.

"The wings also increase running stability as well as the range of inclines the robot can traverse, further increasing the likelihood of a successful mission."

The researchers point out that testing wings on robots could provide an insight into how they evolved in early birds.

Fossils of animals closely related to dinosaurs show that feathers were present on all four limbs, suggesting that the original function was to help animals glide when dropping from a height.

But it's also been suggested that the first wings may have appeared in land-based animals, initially to increase running speed, and leading to take-offs and flying thereafter.

"On the current robot, the wings allow for a stable descent, meaning it can jump from high areas and stably land on its legs at the bottom," says Peterson.

"The wings also increase running stability as well as the range of inclines the robot can traverse, further increasing the likelihood of a successful mission."