How Geckos Clean Their Foot Hair

Wall-climbing robots, bioadhesives or other sticky substances can benefit greatly from a discovery about the self-cleaning and reuse abilities of a gecko’s foot hair by researchers from the University of Akron and the University of North Texas in Denton. 

Day gecko Phelsuma laticauda (Miguel Vences)

Their results were published in the June 13 issue of the Journal of the Royal Society Interface.

The sticky yet clean attribute of this discovery is the gecko toe pad and its ability to repeatedly attach and detach to a surface.

The team discovered that the clue to a dynamic self-cleaning mechanism in gecko setae, or microscopic foot hair, is achieved through the hyperextension of their toes.

“The analysis reveals that geckos have tiny sticky hairs on their toes called setaes, and due to the attaching and detaching mechanism caused by the rolling and peeling motion of their toes as they walk, they release the dirt particles leaving their feet clean,” said lead author Shihao Hu of the University of Akron. “The dynamic hyperextension effect of its natural toe peeling increases the speed of the cleaning to nearly twice as fast as previously perceived.”

The findings show that a gecko-inspired adhesive can function under conditions where traditional adhesives do not, possibly inspiring new applications in space or water exploration tools or in common items like duct tape or other products that use sticky properties.

“Through biomimicry, a gecko-inspired adhesive can function under conditions where traditional adhesives do not, such as in a vacuum, outer space or under water,” said Peter Niewiarowski, a co-author of the study and researcher at the University of Akron.

“More broadly, a gecko-inspired adhesive would be able to bind materials together very strongly yet also release very easily. Imagine a tape that binds things together securely like duct tape yet can also be removed and reused over and over again like a post-it note.”

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Bibliographic information: Hu S., Lopez S., Niewiarowski P.H., Xia Zh. 2012. Dynamic self-cleaning in gecko setae via digital hyperextension. J. R. Soc. Interface. Published online before print June 13, 2012; doi: 10.1098/rsif.2012.0108