Most people think of robots as constructs of hard materials such as chrome, steel and plastic. Those robots are pretty cool, and they can accomplish some amazing things, but they do have one important flaw: if they accidentally smack into you, it's going to hurt. (If they look and move like Arnold Schwarzenegger, they'll hurt even more.)

But a new field of science hopes to eliminate that problem, as well as a few other difficulties posed by hard and rigid robots. As detailed in the scientific journal Soft Robotics, which premiered this week, researchers are looking for ways to make robots that are soft, pliable and safe — not just for people but the environment around them.

"We're excited about soft robots for a variety of reasons," MIT professor of computer science and engineering Daniela Rus said in a news release this week. "As robots penetrate the physical world and start interacting with people more and more, it's much easier to make robots safe if their bodies are so wonderfully soft that there's no danger if they whack you."

Rus and other researchers have put soft robotics to the test by developing a fish-like autonomous robot that has a body made out of flexible silicone. It's capable of bending and twisting, allowing it maneuver easily. And unlike an earlier soft robot fish MIT developed in 2008, it is completely self-contained. The researchers have packed the silicon body not just with a power source but also with the computational power to navigate itself.

The robot does have a few rigid components — most notably the computer "brain," which can receive wireless signals from the researchers' computer — but it eschews normal robotic motors in favor of carbon dioxide, which is pumped into the tail of the robot to allow it to navigate. The researchers say it can flex and change direction in milliseconds — almost as quickly as a real fish. You can see their robot in action in the video below:

The researchers say soft robots could eventually have all kinds of applications that today's robots can't accomplish, including navigating in narrow spaces without worrying about damaging things when they bump into their surroundings.

Other topics covered in the first issue of Soft Robotics include hybrid hard-soft robots, flexible and stretchable electronics, and 3-D printing of soft multimaterial objects.

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