NATIONAL POST (Toronto, Ontario) 06 January 06 Scientist clings to his gecko revolution: Adhesive quality of foot hairs could be applied to robots, medicine, sports (Armando D'Andrea)
A technological revolution that could end the football fumble or stop skidding tires may hinge on the secret of sticky gecko feet.
A study this week in the U.S. journal Proceedings of the National Academy of Sciences reports that the mysterious way the climbing lizards keep their feet clean and sticky -- despite latching on to all kinds of dirty surfaces -- may be replicated in synthetic adhesives.
And for some, such as study co-author Kellar Autumn, there is huge promise in the discovery.
"It'll change the way we assemble things in general," said Dr. Autumn, an associate professor of biology at Lewis & Clark College in Portland, Ore. "We haven't found the glue of the future, we've found the screw of the future."
In what Dr. Autumn said was a harmless and painless procedure, scientists removed gecko foot hairs and attached them to a robot before coating them with dust. The hairs were found to become cleaner and stickier after repeated surface contact.
Dr. Autumn said research suggested this self-cleaning property is dependent on the structure and form of the foot hair rather than a chemical.
"The gecko is not required," he said of how the foot hairs stay clean. "Gecko hair doesn't work with gooey chemicals."
How these small lizards manage to stick to vertical surfaces so comfortably, sometimes by a single toe, had been a mystery for ages.
The tiny hairs, known as setae, are so adhesive that Dr. Autumn said a "gecko's worth" of the hairs could support 130 kilograms.
He believes a synthetic adhesive that cleans itself could be based on gecko feet. Such an adhesive would not get dirty and lose its effectiveness and could be used everywhere from football stadiums to hospitals.
"There is no viable medical adhesive because they're incompatible with the human body," he said. "[Adhesives based on this technology] can be used to replace sutures or implants or pull on nerves or blood vessels very gently. In sports, picture fumble-free football gloves."
Dr. Autum also suggested that an adhesive that can clean itself could be particularly useful in tires, allowing them to stick better to dirty roads.
This same principle could also revolutionize robots moving around on difficult or messy surfaces. Dr. Autumn said the gecko foot hair-based technology might also be used to help exploratory robots tread on Mars and to develop search-and-rescue robots for fire departments to "throw into burning buildings."
While other experts share Dr. Autumn's optimism, some believe further research is required.
"One of the big stumbling blocks will be to produce material that has these properties and will be resistant to wear," said Anthony Russell, a specialist in functional gecko anatomy at the University of Calgary.
"Geckos are small animals ... It depends on what the human application might be. You want it to last for a significant amount of time," he said. "Materials must be sufficiently robust to not wear down rapidly."
Dr. Russell also noted that about 500 gecko species reside in warm climates and it's possible their sticky toes may be a function of where they live.
"It'd be good to have a study to determine the environment's impact on adhesive properties," he said. "Adhesion to something like ice might be different."
But Dr. Russell still agreed the study findings were significant.
"This is a fundamental discovery. This is something we want to do. Until we figure out the basics, we can't progress."
Scientist clings to his gecko revolution