Featured Research

from universities, journals, and other organizations

Bats inspire 'micro air vehicle' designs: Small flying vehicles, complete with flapping wings, may now be designed

Date:
February 18, 2014
Source:
American Institute of Physics
Summary:
By exploring how creatures in nature are able to fly by flapping their wings, researchers hope to apply that knowledge toward designing small flying vehicles known as "micro air vehicles" with flapping wings.

This is the time history of coherent vortex formation around the bat wing. Bottom plot shows lift and thrust coefficient variation for a flapping cycle over normalized time.
Credit: D. Tafti/VT

By exploring how creatures in nature are able to fly by flapping their wings, Virginia Tech researchers hope to apply that knowledge toward designing small flying vehicles known as "micro air vehicles" with flapping wings.

More than 1,000 species of bats have hand membrane wings, meaning that their fingers are essentially "webbed" and connected by a flexible membrane. But understanding how bats use their wings to manipulate the air around them is extremely challenging -- primarily because both experimental measurements on live creatures and the related computer analysis are quite complex.

In Virginia Tech's study of fruit bat wings, the researchers used experimental measurements of the movements of the bats' wings in real flight, and then used analysis software to see the direct relationship between wing motion and airflow around the bat wing. They report their findings in the journal Physics of Fluids.

"Bats have different wing shapes and sizes, depending on their evolutionary function. Typically, bats are very agile and can change their flight path very quickly -- showing high maneuverability for midflight prey capture, so it's of interest to know how they do this," explained Danesh Tafti, the William S. Cross professor in the Department of Mechanical Engineering and director of the High Performance Computational Fluid Thermal Science and Engineering Lab at Virginia Tech.

To give you an idea of the size of a fruit bat, it weighs roughly 30 grams and a single fully extended wing is about 17 x 9 cm in length, according to Tafti.

Among the biggest surprises in store for the researchers was how bat wings manipulated the wing motion with correct timing to maximize the forces generated by the wing. "It distorts its wing shape and size continuously during flapping," Tafti noted.

For example, it increases the area of the wing by about 30 percent to maximize favorable forces during the downward movement of the wing, and it decreases the area by a similar amount on the way up to minimize unfavorable forces. The force coefficients generated by the wing are "about two to three times greater than a static airfoil wing used for large airplanes," said Kamal Viswanath, a co-author who was a graduate research assistant working with Tafti when the work was performed and is now a research engineer at the U.S. Naval Research Lab's Laboratories for Computational Physics and Fluid Dynamics.

This study was just an initial step in the researchers' work. "Next, we'd like to explore deconstructing the seemingly complex motion of the bat wing into simpler motions, which is necessary to make a bat-inspired flying robot," said Viswanath. The researchers also want to keep the wing motion as simple as possible, but with the same force production as that of a real bat.

"We'd also like to explore other bat wing motions, such as a bat in level flight or a bat trying to maneuver quickly to answer questions, including: What are the differences in wing motion and how do they translate to air movement and forces that the bat generates? And finally, how can we use this knowledge to control the flight of an autonomous flying vehicle?" Tafti added.


Story Source:

The above story is based on materials provided by American Institute of Physics. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kamal Viswanath, Krishnamurthy Nagendra, Jeffrey V. Cotter, Matthew Frauenthal and Danesh K. Tafti. Straight-line Climbing Flight Aerodynamics of a Fruit Bat. Physics of Fluids, 2014 DOI: 10.1063/1.4864297

Cite This Page:

American Institute of Physics. "Bats inspire 'micro air vehicle' designs: Small flying vehicles, complete with flapping wings, may now be designed." ScienceDaily. ScienceDaily, 18 February 2014. <www.sciencedaily.com/releases/2014/02/140218114225.htm>.
American Institute of Physics. (2014, February 18). Bats inspire 'micro air vehicle' designs: Small flying vehicles, complete with flapping wings, may now be designed. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2014/02/140218114225.htm
American Institute of Physics. "Bats inspire 'micro air vehicle' designs: Small flying vehicles, complete with flapping wings, may now be designed." ScienceDaily. www.sciencedaily.com/releases/2014/02/140218114225.htm (accessed September 30, 2014).

Share This



More Matter & Energy News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Do Video Games Trump Brain Training For Cognitive Boosts?

Do Video Games Trump Brain Training For Cognitive Boosts?

Newsy (Sep. 29, 2014) More and more studies are showing positive benefits to playing video games, but the jury is still out on brain training programs. Video provided by Newsy
Powered by NewsLook.com
CERN Celebrates 60 Years of Science

CERN Celebrates 60 Years of Science

Reuters - Business Video Online (Sep. 29, 2014) CERN, the European Organisation for Nuclear Research, celebrates 60 years of bringing nations together through science. As Joanna Partridge reports from inside the famous science centre it's also planning to turn the Large Hadron Collider particle accelerator back on after an upgrade. Video provided by Reuters
Powered by NewsLook.com
This 'Invisibility Cloak' Is Simpler Than Most

This 'Invisibility Cloak' Is Simpler Than Most

Newsy (Sep. 28, 2014) Researchers from the University of Rochester have created a type of invisibility cloak with simple focal lenses. Video provided by Newsy
Powered by NewsLook.com
New Corvette Can Secretly Record Convos And Get You Arrested

New Corvette Can Secretly Record Convos And Get You Arrested

Newsy (Sep. 28, 2014) The 2015 Corvette features valet mode – which allows the owner to secretly record audio and video – but in many states that practice is illegal. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins