Soft Robots

Found Robotics

Imagine a flexible suit or garment that you can wrap around an object to turn it into a robot, something that convulsively—compulsively—moves against its will. Researchers at Yale have created a lo-fi version of exactly that: “Robotic skin that bends, stretches and contracts can wrap around inanimate objects like stuffed animals, foam tubes or balloons to create flexible, lightweight robots,” Science News reported last week.

“The researchers achieved different types of motion by altering the layout of air pouches or coils in the skin and by attaching pieces of skin to an object in various configurations,” the report explains. “For instance, wrapping the skin around foam tubes in different orientations created robots that either scooted like inchworms or paddled forward on two ends. Patches of robotic skin around three foam fingers animated a soft robot grabber.”

While the results, at least for the time being, look more like epileptic children’s toys, as you can see in the video embedded above, the idea of giving unnatural movement to the inanimate through an external suit is a compelling reversal of a standard literary narrative. There are so many stories, for example, where something from within—a drug or medicine, a magical spell, an act of demonic possession—causes a person or thing to act strangely, against their will.

Instead, a robotic suit like this makes the source of alien locomotion an exterior one. Put on this clothing, the story would say, and watch yourself change. Like, say, Venom.

In any case, the construction implications of this are also interesting. Rather than assemble materials into a building using nails, screws, or joinery, you could instead wrap those materials up in a particular order inside a geotechnical fabric or cloak; then, using a particular sequence of air pouches and electrical charges, you could watch as previously unconnected materials heave upward and compress like a fist, assembling into some sort of architectural unit.

While this seems useless on any real industrial scale, a series of small architectural sculptures taking shape could make for an interesting gallery installation—a kind of found robotics, enlisting everyday objects into uncanny mechanized forms.

Meshworm

The last few years have seen the rise of “soft robots,” squirming, biomorphic, and highly flexible little machines that can be used to slip through cracks, infiltrate tight spaces, even explore architectural ruins in the wake of earthquakes and warfare.

But soft robots are also getting closer to becoming what are, in effect, mechanically agile medical devices that can “monitor your insides,” in the words of Sangbae Kim, assistant professor of mechanical engineering at MIT, as reprinted by Popular Science, sneaking around inside your body like an earthworm.

The so-called “meshworm” is exactly that: a robotic “worm” made from layered wire mesh that uses “nickel-titanium alloy for muscles.” The application of a high temperature “shortens the wire, tightens the spring’s coil, and squeezes that body segment.” Thus, “when a segment contracts, the one behind it stretches out, and the robot inches forward. The tendon also has muscles attached so the robot can turn left or right.”

The result is the oddly grotesque and somewhat phallic creeping machine you see in the short video, above. The idea is that this could be used for medical diagnosis or vascular surgery.

However, the architectural or broadly spatial uses of this technology are also worth considering, including the potential for monumentally scaled-up versions of the meshworm, capable of assisting human or material transport through the built environment—a kind of peristaltic package-delivery tube that could replace the much-discussed pneumatic tubes of an earlier urban era. Like something out of a David Cronenberg film, the city would have a kind of giant bowel-infrastructure distributing waste material from point to point.

More interestingly, though, this new class of soft robots and meshworms could quickly assume their roles as architectural explorers in their own right, burrowing through collapsed buildings, passing beneath or around doors, even being taken up by the more ambitious burglars and tactical operations teams of the world.

Or, for example, earlier this month in the cave state of Kentucky, the annual “Cave City Hamfest” explored how to bring radio transmission deep underground. This was “accomplished by placing handheld (relay capable) walkie-talkies or relay boxes along a cave passage.” “After the inital debugging phase, we demonstrated the ability to simply walk the cave, until data was lost and then backing up a few feet for a solid link. Then placing a radio on a convenient rock and continuing.” Taking this as our cue, we could simply wire-up a team of meshworms with radio repeaters and send a small, crawling team of spelunking robots far ahead of us into caves where no human body can fit; they would crawl until they lose a signal, move back a few feet to re-establish a secure feed, and then the next one squirms dutifully forward.

You’ve thus built a mobile, semi-autonomous, deep-earth radio network made from repurposed medical devices—equal parts cave-mapping expedition and subterranean pirate radio station—opening up whole new realms of underground exploration (and tactical media).

I’m fascinated by the so-called “chemical robots” program run by DARPA. Its purpose is to create “soft robots”: a “new class of soft, flexible, mesoscale mobile objects that can identify and maneuver through openings smaller than their dimensions and perform various tasks.”

[Image: Video originally seen over at IEEE Spectrum].

These soft machines, DARPA suggests, can be materially realized using “gel-solid phase transitions, electro- and magneto-rheological materials, geometric transitions, and reversible chemical and/or particle association and dissociation.” The idea of a robot that travels via “particle disassociation”—that is, a blurry cloud of “mesoscale mobile objects” that temporarily coalesces into a functioning machine before dissolving again—seems particularly astonishing.

Watch the above video for just one example of a “chemical robot.”

So what would these machines be used for? As DARPA explains: “During military operations it can be important to gain covert access to denied or hostile space. Unmanned platforms such as mechanical robots are of limited effectiveness if the only available points of entry are small openings.”

This is what I imagine Eyal Weizman‘s alter-ego might invent if he went into the robotics business in collaboration with eXistenZ-era David Cronenberg.

I’m specifically reminded of Weizman’s amazing paper, “Lethal Theory” (it is well worth reading the PDF), in which he writes of “microtactical actions” used by the Israeli military as a means of exploring a new domination of the city. The Israeli Defense Force, Weizman writes, has begun strategically retraining itself, in a bid to explore a “ghostlike military fantasy world of boundless fluidity, in which the space of the city becomes as navigable as an ocean.” Soldiers, we read, can now become “so ‘saturated’ within [a city’s] fabric that very few would have been visible from an aerial perspective at any given moment.”

Furthermore, soldiers used none of the streets, roads, alleys, or courtyards that constitute the syntax of the city, and none of the external doors, internal stairwells, and windows that constitute the order of buildings, but rather moved horizontally through party walls, and vertically through holes blasted in ceilings and floors.

This is referred to as “infestation.”

So what if you replaced the living human soldiers with swarms of “soft robots,” capable of squeezing themselves, roach-like, through even the smallest opening? As Weizman terrifyingly suggests later in the paper: “You will never even understand that which kills you.”

Or perhaps we could find a more civilian use, we might say, for these soft machines, and send tens of thousands of them—a storm of flexible swarm-organisms shifting their shapes and flocking—outfitted out with GPS and radar, into the earth, traveling downward via faultlines, where they can map the spheroidal puzzle of our planet.

(Thanks to Alex Trevi for the tip!)