Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Microstructure-induced biomechanical responses of dragonfly wing veins

03.06.2011
Wang's research team discovered the sandwich microstructure of dragonfly wing veins [Wang et al. Compos Sci & Technol, 2008; 68: 186-192] and recently revealed the organic junction between these longitudinal veins and membranes of the dragonfly wing [Chen and Wang et al. Chinese Sci Bull, 2011; 56: 1658-1660].

Based on observed microstructural model and previously reported model about the main longitudinal veins and membrane, in which the former is based on the tubular model with sandwich structure in thickness of tubular, and the latter is based on the sample tubular model with the same material in thickness of tubular, they were used to simulate and characterize the biomechanical responses of dragonfly wings under symmetrical loading.

The results indicated that the effect of different microstructural models on the flapping frequency, trajectories, and corrugated and torsional behaviors of the wing cannot be ignored. This is because the sandwich microstructure, consisting of soft matter with fibers in the protein layer and hierarchical structure in the chitin layer, of the longitudinal vein plays an important role in improving aerodynamic efficiency by creating self-adaptability in the flapping, torsion and camber variations of the wing as it twists. Understanding the complete structure of the wing, including the microstructural features and the organic junction between veins and membranes, provides new insight into the flight mechanism of the dragonfly and the wing's biomechanical responses, as shown by the study reported in issue 56 of the Chinese Science Bulletin and to be reported in the future.

The organic junction with the hierarchical microstructure optimizes the dragonfly wing's biomechanics including to the strength, stiffness and toughness (see Figure 1). The organic junctions enable the corrugation of the total wing along the chord direction, which improves the warping rigidity, while the hierarchical microstructure at the nano scale in the thickness of chitin layer increases the flapping strength of the wing and lift coefficients, but not the torsional rigidity of wing. As the dragonfly wings twist during flapping process, the soft matter with fibers in the protein layer at the micro scale assists the turning performance and allows structural responses between the longitudinal veins and membranes that form the camber of the wing during the three dimensional changes. The camber and zigzag cross-section along the chord direction could enhance the aerodynamic efficiency of the wing [Ennos AR. J Exp Bio, 1988, 140: 137-160; Sane SP. J Exp Bio, 2003; 206: 4191-4208] by creating more vortices under upstrokes and downstrokes, as shown in Figure 2. Moreover, the corrugated wing has an important effect on torsion deformation under sample aerodynamic loading, and it is more flexible than a wing without sandwich longitudinal veins. Thus, the organic junction between the vein and membrane contributes to the dragonfly wing's remarkable biomechanical behavior. In addition, with the help of these two salient features, the wing can easily adjust the its chordwise length by changing the corrugated angle and allowing response to different flight environments. Although it is highly speculative, we believe that the wing possesses some self-adaptabilities to cope with the challenges of flight. From the view of energy, the authors suggest that this kind of self-adaptability helps the dragonfly reduce the amount of energy consumed during flight. Potentially, this research could inspire engineers to design self-adaptable and energy-saving flexible wings for micro aerial vehicles.

The authors are affiliated to the Department of Engineering Mechanics, School of Aerospace, Tsinghua University. This laboratory is conducting research mainly in biomechanics, fatigue damage and fracture mechanics of advanced materials.

Xi Shu Wang | EurekAlert!
Further information:
http://www.tsinghua.edu.cn

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>