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 Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>