05 Feb 2013
Staff Writer
Daniel Burgess / Contributing Writer
With the hope of re-creating one of nature’s incredible abilities, UNT students and professors are examining the qualities of gecko feet and unlocking the secrets of the lizard’s climbing prowess at the Materials Science and Engineering lab at Discovery Park.
Scientists hope to use this new research in designing a reusable, dry adhesive for use on climbing space robots, tires, ATM machines and in medical applications.
The idea is to mimic the creature’s natural climbing abilities, the way airplane designers have mimicked the flight of birds.
“We are testing this nano hair, micro hair and then based on our findings, we are going to build artificial gecko feet,” Associate Professor Dr. Zhenhai Xia said.
The project is part of a collaboration between Xia and Dr. Peter Niewiarowski of the University of Akron Biology department in Ohio.
Without harming the animals, Niewiarowski collects samples of setae – tiny, hair-like structures on gecko feet – and gives them to researchers at Discovery Park, where they are examined using a high-resolution atomic force microscope, said graduate student Quan Xu.
The setae are as small as three microns, which is 30 times thinner than a sheet of paper.
A gecko’s feet have qualities that make it better at sticking to objects than current adhesives and tapes. They can adhere strongly to a surface but release easily, Xia said.
Xia also said the setaeea are self-cleaning, meaning particles do not remain on the foot after stepping on a surface, the way a piece of Scotch tape picks up dust until it is no longer useful.
“If we figure it out, we probably can create some smart tapes that can be repeatedly used many times and also keep strong adhesion,” Xu said. “That is our ultimate goal.”
Xu prepares setae samples and scans them with the microscope. Xu is writing his dissertation on the gecko work.
Xia and Niewiarowski found that the rate of self-cleaning on the setae could be twice as fast as previous studies exhibited.
According to Niewiarowski’s website, Xia made a mathematical model that can accurately predict the behavior of individual setae, but they still don’t understand why the self-cleaning process works the way it does, which affects the ability to stick to a surface.
“Once we are understanding the mechanism behind that, then we can build artificial gecko feet material,” Xia said.
