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February 6, 2020

Imitation Perspiration

One of the hurdles for making enduring, adaptable and agile robots is managing the robots' internal temperature. "Sweating" could let high-powered robots operate for long periods of time without overheating.

Credit: National Science Foundation/Karson Productions

Workin' up a sweat.

I'm Bob Karson with the Discovery Files, from the National Science Foundation.

Sweating cools our bodies by releasing moisture that evaporates, taking some of the heat away with it. Could the same principle work for a robot? Cornell University researchers have been 'sweating the details' to come up with a perspiring robot muscle. A robotic hand with 3D-printed fingers that "sweat." (Sound effect: drip!)

New materials used in soft, flexible robots hold heat -- unlike metals, which cool quickly. Things can get toasty for a robot with high-torque density motors and exothermic engines that power it. If it gets too hot for the bot, (Sound effect: sound of cartoon machine shutdown) it just shuts off.

The team created their robotic fingers from two hydrogel materials, that can retain water and respond to temperature. When the temperature goes above 86 degrees (Sound effect: slide whistle up), the base layer automatically shrinks (Sound effect: slide whistle down), squeezing water into the top layer. That material has tiny pores that dilate and release a small amount of water to the surface. Below 86, the pores close.

The cooling process is very effective, but could the robosweat make the hand slippery? The researchers are working on surface mods -- ridges like fingerprints -- to get a grip on that. They say that 'cause it sweats like us, (Sound effect: cartoon glug glug) it may have to drink like us to replenish fluids.

There ya go. Fist bump? No?

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