Soft robots get their power from the skin they’re in | Science News for Students

Soft robots get their power from the skin they’re in

Given bendy, stretchy skin, everyday objects can morph into useful — or just adorable — robots
Oct 10, 2018 — 6:45 am EST
a horse stuffed animal with white wraps around its legs is walking across a the screen against a black background, electric wires trail behind it

A new bendable, stretchable skin can wrap around inanimate objects — such as this stuffed horse’s legs — creating a soft robot.

J.W. Booth et al./Sci Robotics 2018

A new type of soft robot gets its power from the skin it’s in.

This robotic skin bends, stretches and contracts. That flexibility lets it wrap around inanimate objects. Wrap it around the legs of a stuffed animal and presto! A flexible lightweight robot. Putting removable, reusable sheets of this “skin” on other objects could turn them into useful grippers or wearable devices. Researchers described their new invention online September 19 in Science Robotics.

“It’s an interesting approach,” says Christopher Atkeson. He’s a roboticist at Carnegie Mellon University in Pittsburgh, Pa., who did not work on the project. Sometimes it might be simpler to use a soft ready-made robot for a specific purpose. Like squeezing through tight spaces, for example, or gently grabbing objects. The new robotic skins might come in handy for other things, such as search-and-rescue operations or space exploration. These are missions where users might not know in advance what types of robotic helpers they’ll need. They also are missions where packing light is key, Atkeson notes.

Each piece of robotic skin is made of an elastic polymer (PAHL-ih-murr) or fabric. That stretchy skin can hold air pouches that inflate when pumped full of gas. Or it might hold nickel titanium (Ty-TAY-nee-um) coils that contract when heated by an electric current. Such gas pouches or coils would allow the robotic skin to move and change shape.

Rebecca Kramer-Bottiglio is an engineer at Yale University in New Haven, Conn. She and colleagues used the skin to build several robots. They gave the robots different types of motion two ways. In one, they changed the layout of air pouches or coils in the skin. For the other, they attached pieces of skin to an object in various ways.

For instance, wrapping the skin around foam tubes in one direction created robots that crawled like inchworms. Wrapping it another direction created robots that paddled forward on two ends. Patches of robotic skin around three foam fingers created a soft robot “grabber.”

The researchers also fastened robotic skin to a shirt to create a garment that monitors posture. Whenever the skin sensed the user’s shoulders slumping, it wriggled gently as a reminder to sit up straight. Robotic skin stitched into clothing could give the wearer a massage. Or it could provide tactile (touch) feedback in virtual reality systems, Atkeson says.

The robotic skin isn’t ready for off-the-shelf use just yet. To work, each piece must be tethered to hoses or wires. These feed into its gas pouches or electric coils. But future versions might include portable air pressure and electricity devices, Kramer-Bottiglio says.

Wrapping a robotic skin around a foam tube one way can turn it into a robot that paddles (top). Wrapping it another way creates a robot that moves by inching along (bottom). And even on its own, the skin can scoot across the ground (middle).
J.W. Booth et al./Sci Robotics 2018

Power Words

(more about Power Words)

air pressure     The force exerted by the weight of air molecules.

coil     Concentric rings or spirals formed by winding wire or some other fiber around and around a core; or the shape that such a wire would make.

colleague     Someone who works with another; a co-worker or team member.

current     (in electricity) The flow of electricity or the amount of charge moving through some material over a particular period of time.

electric current     A flow of electric charge — electricity — usually from the movement of negatively charged particles, called electrons.

electricity     A flow of charge, usually from the movement of negatively charged particles, called electrons.

engineer     A person who uses science to solve problems. As a verb, to engineer means to design a device, material or process that will solve some problem or unmet need.

fabric     Any flexible material that is woven, knitted or can be fused into a sheet by heat.

feedback     A response or assessment that follows some a particular act or decision. Or a process or combination of processes that propel or exaggerate a change in some direction. For instance, as the cover of Arctic ice disappears with global warming, less of the sun’s warming energy will be reflected back into space. This will serve to increase the rate of Earth’s warming. That warming might trigger some feedback (like sea-ice melting) that fosters additional warming.

monitor     To test, sample or watch something, especially on a regular or ongoing basis.

nickel     Number 28 on the periodic table of elements, this hard, silvery element resists oxidation and corrosion. That makes it a good coating for many other elements or for use in multi-metal alloys.

online     (n.) On the internet. (adj.) A term for what can be found or accessed on the internet.

polymer     A substance made from long chains of repeating groups of atoms. Manufactured polymers include nylon, polyvinyl chloride (better known as PVC) and many types of plastics. Natural polymers include rubber, silk and cellulose (found in plants and used to make paper, for example).

pressure     Force applied uniformly over a surface, measured as force per unit of area.

robot     A machine that can sense its environment, process information and respond with specific actions. Some robots can act without any human input, while others are guided by a human.

roboticist     Someone who designs or builds robots.

tactile     An adjective that describes something that is or can be sensed by touching.

virtual reality     A three-dimensional simulation of the real world that seems very realistic and allows people to interact with it. To do so, people usually wear a special helmet or glasses with sensors.


Journal: J.W. Booth et al. OmniSkins: Robotic skins that turn inanimate objects into multifunctional robots. Science Robotics. Published online September 19, 2018. doi: 10.1126/scirobotics.aat1853.