This tiny robot tentacle is so accurate it can lasso live ants

Hey, you. Yes, you. Have you always wanted to run an ant rodeo, but were concerned that you’d crush the poor critters with your lasso? Well, start working on your flyers, because materials scientists from Iowa State University have come up with a robotic tentacle so delicate that it can grab an ant without crushing it.

This combination of gentle and precise has eluded robotics for quite some time, and has all kinds of potential implications for surgery and biology.

So just how gentle are we talking? The tentacle can grab ants and fish eggs with a grip that’s 0.78 micronewtons of force. How crushing is that? Blink your eyes – thousands of times softer than that, according to Popular Mechanics.

The tentacle is crafted from polydimethylsiloxane (henceforth referred to as PDMS for the sake of our overworked sub-editors), a silicone compound that’s both cheap and soft. The PDMS is moulded into hollow tubes that curl when air is extracted. One side of the tube is thinner than the other to ensure that the tentacles curl in a uniform way for precise grabbing.

One problem the scientists had to overcome was the viscous liquid form PDMS takes. They got around this dilemma by heat-treating it to make it more malleable. This allowed them to set the mixture around optical fibres, which could then be stripped away, leaving the hollow tubes.

“Two of the biggest trends in robotics right now are soft robotics – utilising soft materials for purposes like gentler human interaction – and micro-robotics, making robots smaller,” Dr Jaeyoun Kim, the scientist who led the team, told Popular Mechanics. “These micro-tentacles fuse those together.”

The result is the delicate micro-tentacle you see in the pictures above – able to grab an ant by the waist, or extract a fish egg without crushing it. Because the super-soft tentacles spread the force across their entire five- to eight-millimetre length, the touch is far more delicate than the dual pinchers usually seen on robots.

Microsurgery is the most obvious beneficiary of the new technology. As Kim says, “there’s a great benefit to utilising tools you know can’t accidentally damage the tissue around where you’re working.”