'Micro-aircraft' inspired by insect flight comes closer to reality

Washington, September 18 (ANI): A "micro-aircraft" inspired by the manoeuvrability and energy efficiency of an insect may have come closer to reality, for scientists have successfully decoded the aerodynamic secrets of insect flight.

Dr. John Young, from the University of New South Wales (UNSW) in Australia, and a team of animal flight researchers from Oxford University's Department of Zoology, used high-speed digital video cameras to film locusts in action in a wind tunnel, capturing how the shape of a locust's wing changes in flight.

The researchers revealed that they used the information thus gathered to create a computer model, which recreates the airflow and thrust generated by the complex flapping movement.

Writing about their breakthrough in the journal Science, they said that their findings might enable engineers to create miniature robot flyers for use in situations like search and rescue, military applications, and inspecting hazardous environments.

"The so-called 'bumblebee paradox' claiming that insects defy the laws of aerodynamics, is dead. Modern aerodynamics really can accurately model insect flight," said Dr. Young, a lecturer in the School of Aerospace, Civil and Mechanical Engineering at the Australian Defence Force Academy.

"Biological systems have been optimised through evolutionary pressures over millions of years, and offer many examples of performance that far outstrips what we can achieve artificially.

"An insect's delicately structured wings, with their twists and curves, and ridged and wrinkled surfaces, are about as far away as you can get from the streamlined wing of an aircraft.

"Until very recently it hasn't been possible to measure the actual shape of an insect's wings in flight - partly because their wings flap so fast, and partly because their shape is so complicated.

"Locusts are an interesting insect for engineers to study because of their ability to fly extremely long distances on very limited energy reserves," Dr. Young said.

Once the computer model of the locust wing movement was perfected, the researchers ran modified simulations to find out why the wing structure was so complex.

In one test, they removed the wrinkles and curves but left the twist, while in the second test they replaced the wings with rigid flat plates.

According to them, the simplified models produced lift, but were much less efficient because they needed much more power for flight.

"The message for engineers working to build insect-like micro-air vehicles is that the high lift of insect wings may be relatively easy to achieve, but that if the aim is to achieve efficiency of the sort that enables inter-continental flight in locusts, then the details of deforming wing design are critical," Dr. Young said. (ANI)