Roach-inspired robot nearly as fast as real thing, unsquashable

July 31 (UPI) -- If you see the latest robot from the University of California, Berkeley scurrying across your kitchen floor, don't bother trying to step on it. The novel roach-like robot, described this week in the journal Science Robotics, can't be squashed.

The new robot, developed by engineers at Cal, can run nearly as fast as a cockroach and as is even harder to kill. If one were to stomp on the little robot, the durable electronic bug would likely emerge unharmed.

"Most of the robots at this particular small scale are very fragile. If you step on them, you pretty much destroy the robot," Liwei Lin, a professor of mechanical engineering at Berkeley, said in a news release. "We found that if we put weight on our robot, it still more or less functions."

It's small stature, speed and durability could help the robot -- perhaps, an army of them -- survey dangerous terrain in the wake of disaster, like a burned-out building or collapsed bridge.

"For example, if an earthquake happens, it's very hard for the big machines, or the big dogs, to find life underneath debris, so that's why we need a small-sized robot that is agile and robust," said Yichuan Wu, who recently finished his graduate degree in mechanical engineering at Berkeley.

Wu now works as an assistant professor at the University of Electronic Science and Technology of China.

The stamp-sized robot is made from a small tab of polyvinylidene fluoride, a piezoelectric material. When an electric current runs across piezoelectric materials, they expand or contract. Researchers at Cal coated the piezoelectric tab with an elastic polymer, which caused the robot to bend instead of expand or contract.

Researchers attached legs so that as the robot's body bends and straightens in response to the electric current, the robo-roach performs a leapfrog maneuver, propelling it forward. The robot tops out at speeds of 20 body lengths per second, one of the fastest recorded speeds among insect-scale robots.

In addition to speeding across flat surfaces, the robot can climb small slopes and carry light loads. Most impressively, the tiny robot, which weighs less than one tenth of a gram, can withstand the pressure of 132 pounds.

"People may have experienced that, if you step on the cockroach, you may have to grind it up a little bit, otherwise the cockroach may still survive and run away," Lin said. "Somebody stepping on our robot is applying an extraordinarily large weight, but [the robot] still works, it still functions. So, in that particular sense, it's very similar to a cockroach."

For now, the miniature robot's electric current is supplied by an electric wire, keeping the robo-roach tethered. Researchers are currently working to outfit the robot with a battery so that it can roam freely.