A new robot is able to not only walk on water — it can jump on water. The robot is designed to mimic the leaping motions of water striders, those little wisps of insects that dimple the surfaces of creeks in the summertime. The new robot can jump about five and a half inches (14 centimeters) high and 14 inches (35 cm) forward, even though it weighs more than 1,000 times as much as one water strider insect.
Over the past few years, several robotics labs have created tiny bots that are able to walk or skate across the surface of the water, but this is the first that can jump. A jumping robot water strider is more agile than a skating one, so it's able to avoid obstacles, the robot's creators, researchers from the Harbin Institute of Technology in northern China, wrote in a paper they published July 25 in the journal ACS Applied Materials & Surfaces. In the future, an agile, jumping robot may spy for governments or monitor water quality, they wrote.
Water striders, both biological and robotic, rely on water tension to keep them aloft. It's difficult to design a robot, however, that can produce the downward force needed to propel it off the surface of the water without breaking the water's surface tension. The Harbin researchers solved the problem by forming their robot's feet from what they called a super water-repelling "nickel foam."
The robot has three wide, flat feet for stabilizing it on the surface of the water and two thinner, paddlelike feet for jumping. Motors in the middle of its body move the jumping feet. The nickel material in the feet helps reduce the energy needed to push the robot off the water, the researchers found.
Wired posted this video of the jumping robot at work. It's impressive, but also a little unsettling to see that water-strider shape, writ extremely large in comparison to the natural insect: