Shape-shifting paper could help tiny bots take flight

A new breakthrough in materials science may pave the way for those inevitable swarms of tiny flying robots that will one day darken the skies and strike fear into us all, as researchers in South Korea have succeeded in coaxing specially-prepared cellophane paper to rapidly curve and straighten itself in an insect-like flapping motion. Although scientists have apparently known since the 1950's that wood was piezoelectric, meaning that it bends slightly when exposed to electricity, it took a team from Inha University with help from Texas A&M to discover that the same property also holds true for other cellulose-based material. By coating both sides of a sheet of cellophane with thin layers of gold, the researchers were able to create so-called Electroactive paper (EAPap) so sensitive that the voltage from a microwave beam provides enough power to trigger its unique shape-changing abilities. Oddly enough, no one is quite sure of the physics behind the transformation -- theories center around pressure changes resulting from the movement of ions -- but regardless of how it works, we're sure that more than a few governments will be most interested in deploying this technology to beef up their domestic and international surveillance programs.

[Via Roland Piquepaille and ScienceNOW]