These robot bugs don't just walk on water, they jump on it

An international team has developed robot water-striders. Is this more evidence of a coming awesome robot apocalypse?

Eric Mack Contributing Editor
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Eric Mack
2 min read

We know at least one story about walking on water, and we've even seen a Chinese robot with this superpower, but now a team of engineers from Harvard and Korea's Seoul National University (SNU) has made the next leap and figured out how to build tiny robots that can also jump where most others sink.

By mimicking the mechanics of a familiar insect -- the water strider -- the team was able to create a small robot that can not only stride across the surface of water, but actually leap upward from it in much the same way as the actual bug.

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Will our robot overlords be smaller than we thought? Seoul National University

"Water's surface needs to be pressed at the right speed for an adequate amount of time, up to a certain depth, in order to achieve jumping," SNU's Kyu Jin Cho said in a release. "The water strider is capable of doing all these things flawlessly."

In addition to having just the right timing and touch to launch from a wet surface without sinking, real-life striders also have legs with slightly curved tips. These tips increase the area the insects use to press against the surface of the water with a maximum amount of force, but without breaking the surface tension that keeps them on top of the water.

After studying how a water strider jumps in concert with the development of a series of iterative robot prototypes, the team successfully hit on a model that mimics the real bug by exerting up to 16 times its own weight on the water's surface without breaking through.

"The resulting robotic insects can achieve the same momentum and height that could be generated during a rapid jump on firm ground -- but instead can do so on water -- by spreading out the jumping thrust over a longer amount of time and in sustaining prolonged contact with the water's surface," explained Harvard's Robert Wood, a co-author of a paper on the work published Friday in the journal Science.

How will these robots be used? Well, the research was funded in part by South Korea's Defense Acquisition Program Administration, so it's not inconceivable to imagine an army of robot water striders swimming over the border to North Korea and hopping out of the water to keep an eye on Kim Jong Un.

Or maybe these robot fish just need something to chase. Either way, check them out for yourself in the video below and let us know in the comments if you find them to be more cool or creepy.