Robot hand ‘sweats’ to stay cool

In order to keep these materials cool, an internal fan is required — which adds unwanted weight and bulk.

Shepherd worked with Cornell engineering professor Emmanuel Giannelis and T.J. Wallin, a research scientist at Facebook Reality Labs, to find a solution.

They developed a hydrogel material that squeezes water from a series of tiny pores that automatically dilate when the temperature hits 86 F (30C), and close when the temperature falls beneath that.

This method of thermal management means the robot can be operated for long periods of time without overheating, researchers said.

“Sweating takes advantage of evaporated water loss to rapidly dissipate heat and can cool below the ambient environmental temperature.”

Wallin added: “So as is often the case, biology provided an excellent guide for us as engineers.”

“Fluid excretions could be used to change the friction between surfaces and allow for smooth movement, particularly useful for directing the locomotion of crawling or sliding robots,” the researchers wrote.

The technology could also be used for “digesting” and “absorbing” — such as removing contaminants from a surface.

The researchers did, however, find the invention presented one potential challenge: There is a need for robots to replenish the water supply, which means one day robots may also need to “drink” like mammals, as well as sweat like them, to stay cool.

“Similar to animals that ingest food and water from their environment to sustain thermoregulated activity, our demonstrated system eventually requires a means to replenish lost water during extended operation,” they wrote in Science Robotics.