Wings for Drones

LONDON: A US-based scientist of Indian origin has developed a new mechanism based on the flapping wings of birds to power micro air vehicles, helping them bear the brunt of gusts of wind.
“Making things mimic nature is much more difficult than it might seem,” said Sunil Agrawal, director of the Mechanical Systems Laboratory at the University of Delaware. “It is scientifically fascinating, but also extremely challenging.”
The problem that most micro air vehicles face is that they are easily pushed off course by light gusts of wind.
Nature’s answer to this problem is to give small birds wings that can be flapped in bursts to avoid sudden gusts.
But human engineers have found it hard to build a flapping mechanism that is both light and efficient enough to get ornithopters off the ground while also carrying a suite of instruments such as a camera and a radio transmitter.
One problem is that flapping is not a simple up and down movement, but a complex series of motions that include rotating the wing to “feather” it in the upward part of a stroke.
Now, Agrawal and colleagues have solved this problem by building a flapping mechanism for micro air vehicles that is powered by a single actuator.
The mechanism can be used in a micro air vehicle with a wing span of less than 15 centimetres.
“We want to show that the flappingwing machines can be built,” Agrawal said. “Eventually, we would like to expand from a single flying machine to a group of cooperative flying machines.”
As well as powering an ornithopter, the mechanism could be used to create a flapping air current, or to propel an underwater vehicle. ANIA file photo of Sunil Agrawal (right), professor of mechanical engineering, and research assistant Zaeem Khan inspecting one their robotic “birds” .This article is orignally published in Mumbai mirror news paper.