Engineers from Cornell University (USA) have developed a small device called SECAD that uses thesurface tension of water to adhere to any surface. Ingenuity, they predict, will allow us to walk through walls emulating Spiderman himself.
As published today by Paul Steen and Michael Vogel in the magazineProceedings of the National Academy of Sciences(PNAS), theinvention, what isinspired by a native Florida beetlethat can adhere to the sheets with a force 100 times greater than its weight, it consists of a flat sheet filled with microscopic holes attached to a liquid plate and another thin porous layer. When an electric field is applied to the assembly using aconventional 9 volt battery, the water is pumped through the appliance (electroósmosis), causing small drops to reach the top layer. The surface tension of water allows the device to adhere to any surface in the same way that two crystals “stick” with just a few drops of liquid. And with hardly any energy consumption.
“In everyday life these forces are relatively weak,” explains Paul Steen. “But if we create a lot and control them, like the beetle does, we can get a strong grip,” he adds. One of the first prototypes, with a thousand holes, can hold 30 grams. And the smaller these holes are, the more their adhesive power grows. For example,using an area of 2.5 square centimetersWith millions of holes just one micron in diameter, the gadget couldsupport more than 6 kilograms of weight on the ceiling or wall.
