Soft Bots Get Out of Tight Spots

Soft-bodied robots are able to squeeze into tight places while still maintaining their strength and gripping power.

For decades, most people have seen robots as upright, rigid, humanoid machines with gleaming chrome body parts, perhaps glowing red eyes and clunky movements. But many researchers and engineers are switching gears, seeking instead to build robots that move like the body of an octopus, a caterpillar, Venus fly-trap, flea or folded paper origami.

"Soft robotics" is challenging traditional robotics as a way of building devices that are better integrated with the natural environment, moving the ways that animals do.

The goal is to design robots that mimic the movements of creatures who have evolved over millions of years, while still accomplishing the tasks that people need robots for in the first place, like exploring dangerous areas, picking up and moving things or doing repetitive tasks.

"It was a big change for me," Cecilia Laschi, professor at the Biorobotics Institute at the Scuola Superiore Sant'Anna in Pisa, Italy, said about her conversion to the field. "I realized that if we want to use neuroscience or brain models to control robots, we also need to look at a different body. We have to look at animals and plants, they have a lot of soft parts."

Soft-bodied robots can get smaller, squeeze into tight places, deform their shape and still maintain strength and gripping power, Laschi said.

Her robot octopus, for example, is designed to explore underwater nooks and crannies of shipwrecks, coral reefs and drilling operations. It uses an artificial muscle of a special braid of plastic fibers embedded in silicon.

Similar human-like soft robots can also exert fine motor control, and a gentle touch. That might be important when for a robot that has to handle delicate gourmet chocolates, cookies or silicon chips on an assembly line, according to Laschi.

Soft robotics includes everything from new endoscopic surgical tools that can grip and harden inside the human body like an octopus tentacle, to a flexible exo-skeleton hidden beneath a uniform to give a soldier (or athlete or injury patient) an extra power boost.

Many of these soft devices were on display this week at the International Conference on Intelligent Robots and Systems (IROS 2014) in Chicago, including Harvard University' squishy flesh-colored three-limbed robot or an external mask worn around the face -- made from rubber, wire and fabric -- to help patients who have trouble eating or talking.

Laschi said the number of researchers and academic labs building soft robots has skyrocketed in the past few years, enough for the field's own journal, Soft Robotics, that launched recently.

"If you need a robot for an industrial factory, a traditional robot is better," Laschi said. "We have 50 years of knowledge about how they work. But if you want to put a robot in a house or park or city or hospital, then you need something different."

The biggest challenge for engineers working on soft robots is figuring out actuation, or the devices that cause movement, as well as gripping, according to Kyuchin Cho, director of the Biorobotics Institute at Seoul Natinal University in Korea. "If you try to grab something, you need precise control. Softness makes it a lot easier," he said.

Cho is modeling robotic devices on the quick-closing hinge of a Venus fly-trap, as well as a soft robotic glove to help patients with paralysis injuries.

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"If you look at the fly-trap, it's very simple, but can close in a short amount of time, within .1 seconds," Cho said. "If you look at the structure, it has a much simpler link and joint mechanism. They have stability their structure."

Cho doesn't believe soft robots will ever work on factory floors assembling cars, for example, or be sent in to defuse bombs. But expect to see more of them crawling, scooching and slithering their way into our doctor's offices and workplaces in coming years.

This inflatable snake robot can curl around a rigid maze.

The fast and maneuverable Naro-Tartaruga will have pressure, temperature, water leakage and water flow sensors, along with gyros, GPS and a compass to navigate.