Scientists design robots that walk on water

An aquatic microrobot can walk or run on water, mimicking the amazing abilities of the 'water strider',a long legged insect that effortlessly skims across pond and lakes surfaces.

The bionic bot is a vast improvement over previous devices of this kind that position it as a prime candidate for military spy missions, water pollution monitoring and other applications, the scientists say.

Even though the microrobot weighs as much as 390 water striders, it does not sink when placed on water, but stands, walks and runs effortlessly on its surface, the journal Applied Materials & Interfaces reports.

"Walking on the water surface is a dream of humans, but it is exactly the way of life for some aquatic insects," says Zhejiang University associate professor of chemical engineering Qinmin Pan, who has achieved this rare feat.

Other scientists have made tiny aquatic devices based on the water strider. But until now, no one has found a way to make water-walking robots that are practical, agile, and inexpensive, according to a Zhejiang statement.

The new robot has a body about the size of a quarter; 10 water-repellent, wire legs; and two movable, oar-like legs - propelled by two miniature motors.