Tiny microrobotic tentacles could be used to safely handle even the most delicate objects.

A team of researchers demonstrated the micro-tentacles could pick up a live ant without harming it, Iowa State University reported.

"Most robots use two fingers and to pick things up they have to squeeze," said Jaeyoun (Jay) Kim, an Iowa State University associate professor of electrical and computer engineering and an associate of the U.S. Department of Energy's Ames Laboratory. "But these tentacles wrap around very gently."

To create these remarkable tentacles, the researchers fabricated microtubes that were only eight millimeters long and less than a hundredth of an inch wide using the transparent elastomer PDMS. One end of each individual tube is sealed, and air is pumped in and out. The air pressure creates a circular bend, and a small lump of PDMS (which can be either a liquid or rubbery solid) is injected into the bease of the tube to amplify the bend and create a coiling action.

"Spiraling tentacles are widely utilized in nature for grabbing and squeezing objects," the engineers wrote in the paper, which was published in a recent edition of the journal Scientific Reports. "There have been continuous soft-robotic efforts to mimic them..., but the life-like, multi-turn spiraling motion has been reproduced only by centimeter-scale tentacles so far. At millimeter and sub-millimeter scales, they could bend only up to a single turn."

The new production technique that was used to build the microtubes helped solve these problems and allow for the production of the ultra-precise devices. These micro tentacles could be used in medical procedures because they cannot damage tissue or blood vessels.

"There's microrobotics, where people want to make robots smaller and smaller. And there's soft robotics, where people don't want to make robots out of iron and steel. This project is an overlap of both of those fields. I want to pioneer new work in the field with both microscale and soft robotics," Kim concluded.