Oregon State University researchers have discovered the secret behind geckos' ability to stick to surfaces: toe hairs.
Geckos can turn these sticky follicles off and on based on the consistency of the surface upon which they sit.
"It was only very recently, in 2000, that Kellar Autumn and colleagues proved unequivocally that geckos stick using van der Waals forces," said co-author of the study and assistant professor of engineer at OSU, Alex Greaney.
The "Van der Waals forces" refers to the forces of nature characterized by weak atomistic levels. Researchers found that the geckos can use these forces within their environment to help them stick and move about on various kinds of surfaces.
The team also discovered that the process of turning the stickiness of the toe hairs on or off is a very complex one that involves the lizard's combination of extensibility and flexibility. This ability enables the gecko to fasten itself to any surface while allowing the animal to also unstick itself anytime without using too much energy.
Potential applications of this research include the creation of synthetic dry adhesives. These sticking agents could be used in climbing, military, and rescue activities. To date, experiments with dry adhesives have been conducted using robots. It can also be used as basis for the improvement of synthetic adhesives.
"While we don't envision Mission Impossible sticky gloves, which are inspired by or based on the concept of gecko adhesion, we envision that robots will use gecko adhesion in extreme environments in the future," Greaney said.
Findings of the study were published in the Aug. 13 issue of the Journal of Applied Physics.
