Sitti Uses Biology to Print Electronics on Complex Surfaces
Carnegie Mellon University's Metin Sitti has used his work with
lizard geckos to inspire a new method to print electronics on complex
Sitti, an innovative and leading-edge professor of mechanical engineering at CMU, and a team of academic colleagues in the U.S., have developed a reversible adhesion method for printing electronics on a cache of sticky surfaces, such as clothing, plastics and leather.
The research appeared in a recent Proceeding of the National Academy of Science (PNAS) paper titled, "Microstructural Elastomeric Surfaces with Reversible Adhesion and Examples of Their Use in Deterministic Assembly by Transfer Printing."
"This work gives us the opportunity to transfer and print electronics on complex surfaces," said Sitti, director of the Nanorobotics Lab at Carnegie Mellon. "The team designed a square polymer stamp with pyramid micro-tips that allows them to control adhesion strength."
Like the geckos, which are wizards at sticking to any kind of surface, the new polymer stamp also features a distinct adhesive quality. Key to the square polymer stamp is four pyramid-shaped micro-tips on the stamp's bottom. They mimic the micro- and nano-hairs on the gecko's foot, which the animal uses to control adhesion by increasing or decreasing their contact surface area.
The researchers conducted tests of the stamp and found the changes in the contact area allow the stamp's adhesion strength to vary by 1,000 times. They also demonstrated their method can print layers of electronics, enabling the development of a variety of complex devices.
"This is a breakthrough in the way we will be able to bundle complex electronics to a variety of industry sectors," Sitti said.
For more than a decade, Sitti has been designing and fabricating gecko-inspired fibrillar structures as new repeatable adhesives. He founded nanoGriptech LLC last year to commercialize these new materials for sports, medical devices, robotics, defense and space applications.
"There is really no limit to what the gecko-adhesives and nature teach us as we continue to explore new opportunities," he said.