Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Multiple Factors Affect Flight Power Curves Among Species

23.01.2003


Researchers using three dimensional computer modeling and wind tunnels have made the first accurate comparative measurements of muscle power output of birds in-flight to establish that physical structure, body mass, force and flight style all have major effects upon the magnitude and shape of a species’ power curve.

The research by Harvard integrative physiologist Andrew A. Biewener and fellow researchers was publicly funded through the National Science Foundation (NSF) and published in the Jan. 23 edition of Nature.

NSF is an independent federal agency that supports fundamental research and education across all fields of science and engineering.



The research has broad-ranging impact since the power curves provide graphical insight into how muscles are used to produce power for flight at different speeds. Knowledge of flight capabilities would be useful in natural environment studies of issues such as bird migration and a bird’s flight ecology. The data might also be useful in the development of more efficient robotic aerial vehicles, where factors such as thrust and forward velocity are paramount.

Birds were used in the study because they rely primarily upon a single pectoralis muscle in each wing to fly. It is difficult to measure mechanical power output in other animals since most use multiple, distributed muscles for locomotion. In comparison, humans have 45 muscles in the thigh, leg and foot region alone, most of which are active during locomotion.

The researchers established mechanical power curves for cockatiels (Nymphicus hollandicus) and turtledoves (Streptopelia risoria) by measuring the wing and body movements as the birds flew at various speeds in a wind tunnel. They also used high-speed video to record from multiple angles the length changes of the birds’ pectoralis muscle. These data were applied to a computer model of aerodynamic power output. When analyzed with other data collected, the researchers were able to calculate minimum and maximum power outputs for the birds.

The cockatiel and turtledove data were compared to the power curve of magpies, which had been studied previously. It was found that cockatiels and turtledoves generate more power in linear flight than do magpies, which achieve maximum power output during hovering.

The researchers attribute the difference to the individual physical structure and shape of the birds’ tails and wings. Compared to cockatiels and turtledoves, magpies have broad, rounded wings and a longer tail that likely increases drag and prevents it from flying faster than 14 meters per second (31.36 mph) despite it having sufficient pectoralis power to fly at faster speeds. Instead, its wings are better suited for flight at lower speeds and likely allow it to maneuver more effectively.

In contrast, the researchers concluded that turtledoves and cockatiels, which have pointed wings and proportionally smaller tails, can sustain much faster flight speeds. Top speed for a cockatiel is about 14 meters per second (31.36 mph), while turtledoves can achieve 17 meters per second (38.08 mph). In comparison, Tim Montgomery, the current "world’s fastest human," achieved a top speed of about 22.9 mph in the 100-meter dash. The differences in the power curves of the three studied species are most apparent at faster speeds.

The researchers said that flight style may explain power curve differences between the birds studied and magpies. Magpies combine a fluctuating wing beat gait, speed and altitude for an intermittent flight style. Cockatiels and turtledoves use more regular wing motions to fly over a range of speed.

The researchers noted that the maximum mass-specific power output of cockatiels and doves, which can fly for hours before tiring, is 60 percent less than estimated for "galliforms." Galliforms are pheasant-like birds with short, broad wings. Their pectoralis muscles have greater mass and are capable of providing power "bursts," which the birds use to take flight quickly to escape danger before rapidly tiring and returning to the ground to run or hide.

-NSF-

NSF is an independent federal agency that supports fundamental research and education across all fields of science and engineering through an annual budget of nearly $5 billion. NSF funds reach all 50 states through grants to nearly 2,000 universities and institutions. Each year, NSF receives about 30,000 competitive requests for funding and makes about 10,000 new funding awards. NSF also awards more than $200 million annually in professional and service contracts.

Media contact:
Manny Van Pelt
(703) 292-8070
mvanpelt@nsf.gov

Program contact:
William E. Zamer
(703) 292-8421
wzamer@nsf.gov

Principal Investigator:
Andrew A. Biewener
(781) 275-1725
abiewener@oeb.harvard.edu

Manny Van Pelt | NSF
Further information:
http://www.nsf.gov
http://www.nsf.gov/home/news.html

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>