Researchers evaluate mosquitoes' ability to float on water in order to potentially design aquatic robots
Small semi-aqueous arthropods, such as mosquitoes and water striders, are free to go about their waterborne business thanks to their unique leg-based adaptations, which repel water and allow them to float freely on the surface.
By examining the forces that the segments of mosquito legs generate against a water surface, researchers at the China University of Petroleum (Huadong) and Liaoning University of Technology have unraveled the mechanical logic that allows the mosquitoes to walk on water, which may help in the design of biomimetic structures, such as aquatic robots and small boats.
"The current analyses deepen our understanding of the mechanisms of water-walking of these aquatic insects," said Jianlin Liu, a professor in the Department of Engineering Mechanics at the China University of Petroleum. They describe their current research in the journal AIP Advances, from AIP Publishing.
Mosquitoes land on still bodies of water to lay their eggs just under the surface, where the embryos will hatch and develop into a pupa, eventually emerging from the water as a mature adult to continue the cycle.
A mosquito leg consists of three segments coated in grid-like, microscopic hydrophobic scales: a stiff femur juts out from the insect's abdomen and connects at a joint to an equally stiff tibia, which branches into a long, flexible tarsus. Previous measurements of the ability of water surfaces to support insects had largely ignored the tarsus, however, focusing instead on whole legs.
The researchers measured the buoyant force produced by the tarsus by adhering a mosquito leg to a steel needle, which was attached to an indenter column and microsensor. This in-situ setup allowed them to adjust the angle and force between the leg and the water's surface, while taking readings with an optical microscope and digital camera.
Liu and his colleagues found that the insect's ability to float on water - generating an upward force of twenty times its own body weight with its six legs - is owed entirely to the tarsus's buoyant horizontal contact with the surface.
"This finding overthrows the classical viewpoint that the longer the mosquito leg, the more efficiently it produces buoyant force," Liu said.
By reducing the total surface area of the leg in contact with water, the adhesive force of the water on the insect is greatly reduced, which assists in takeoff.
The structural ability of the tarsus to achieve such a large supporting force per unit length, however, remains an ongoing research endeavor for the team. Future work for Liu and his colleagues involves studying the microstructures, wet adhesive forces and dynamic behavior of mosquito legs.
The article, "Load-bearing ability of the mosquito tarsus on water surfaces arising from its flexibility,” is authored by Xiang-qing Kong, Jianlin Liu, Wen-jiao Zhang and Qu Yandong. It will appear in the journal AIP Advances on March 3, 2015 (DOI: 10.1063/1.4908027). After that date, it can be accessed at: http://scitation.aip.org/content/aip/journal/adva/5/3/10.1063/1.4908027
ABOUT THE JOURNAL
AIP Advances is a fully open access, online-only, peer-reviewed journal. It covers all areas of applied physical sciences. With its advanced web 2.0 functionality, the journal puts relevant content and discussion tools in the hands of the community to shape the direction of the physical sciences. See http://aipadvances.aip.org
Jason Socrates Bardi
Jason Socrates Bardi | newswise
IceCube experiment finds Earth can block high-energy particles from nuclear reactions
24.11.2017 | Penn State
New proton record: Researchers measure magnetic moment with greatest possible precision
24.11.2017 | Johannes Gutenberg-Universität Mainz
High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons
The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
24.11.2017 | Physics and Astronomy
24.11.2017 | Health and Medicine
24.11.2017 | Earth Sciences