MacGregor Campbell, contributor
Leaping lizards can land steadily on vertical walls by adjusting their tails mid-flight. Taking inspiration from the reptiles, Robert J. Full at the University of California, Berkeley and his team have equipped a new wheeled robot with a weighted tail to mimic this ability.
The artificial tail can be actively controlled to swing up or down, counteracting the mass of the robot's main body. In this video, you can see how it helps the robot when it's dropped nose-first during a trial. With a quick swing of the tail, the robot rights itself and lands with its wheels on the ground. A second clip shows how the tail is also useful during ground-based manoeuvres. Rolling over bumps causes a tail-less version of the bot to lose control, landing helplessly on its side. But with the extra appendage, it gets a slight boost which keeps it horizontal, allowing it to hop over the obstacles and continue on its way.
Such biologically inspired engineering could be incorporated into robots operating in rough terrain to facilitate search-and-rescue operations.
Journal reference: Nature, DOI: 10.1038/nature10710