Gumby-like flexible robot crawls in tight spaces (w/ video)

Gumby-like flexible robot crawls in tight spaces (w/ video)

Harvard scientists have built a new type of flexible robot that is limber enough to wiggle and worm through tight spaces.

It's the latest prototype in the growing field of soft-bodied robots. Researchers are increasingly drawing inspiration from nature to create machines that are more bendable and versatile than those made of metal.

The Harvard team, led by chemist George M. Whitesides, borrowed from squids, starfish and other animals without hard skeletons to fashion a small, four-legged rubber robot that calls to mind the clay animation character Gumby.

In recent years, scientists have been tinkering with squishy — sometimes odd-looking — robots designed to squeeze through hard-to-reach cracks after a disaster like an earthquake or navigate rough terrain in the battlefield.

"The unique ability for soft robots to deform allows them to go places that traditional rigid-body robots cannot," Matthew Walter, a roboticist at the Massachusetts Institute of Technology, said in an email.

A team from Tufts University earlier this year showed off a 4-inch caterpillar-shaped robot made of silicone rubber that can curl into a ball and propel itself forward.

The Harvard project, funded by the Pentagon's research arm, was described online Monday in the journal Proceedings of the National Academy of Sciences.

The new robot, which took two months to construct, is 5 inches long. Its four legs can be separately controlled by pumping air into the limbs, either manually or via computer. This gives the robot a range of motions including crawling and slithering.

The researchers tested the robot's flexibility by having it squirm underneath a pane of glass just three-quarters of an inch from the surface.

Scientists maneuvered the robot through the tiny gap 15 times using a combination of movements. In most cases, it took less than a minute to get from side to side.

Researchers eventually want to improve the robot's speed, but were pleased that it did not break from constant inflation and deflation.

"It was tough enough to survive," said Harvard postdoctoral fellow Robert Shepherd, adding that the robot can traverse on a variety of surfaces including felt cloth, gravel, mud and even Jell-O.

There were drawbacks. The robot is tethered to an external power source and scientists need to find a way to integrate the source before it can be deployed in the real world.

"There are many challenges to actively moving soft robots and no easy solutions," Tufts neurobiologist Barry Trimmer, who worked on the caterpillar robot, said in an email.

Robotics researcher Carmel Majidi, who heads the Soft Machines Lab at Carnegie Mellon University, said the latest is innovative even as it builds on previous work.

"It's a simple concept, but they're getting lifelike biological motions," he said.

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More information: Multigait soft robot: Published online before print November 28, 2011, doi: 10.1073/pnas.1116564108

This manuscript describes a unique class of locomotive robot: A soft robot, composed exclusively of soft materials (elastomeric polymers), which is inspired by animals (e.g., squid, starfish, worms) that do not have hard internal skeletons. Soft lithography was used to fabricate a pneumatically actuated robot capable of sophisticated locomotion (e.g., fluid movement of limbs and multiple gaits). This robot is quadrupedal; it uses no sensors, only five actuators, and a simple pneumatic valving system that operates at low pressures (< 10 psi). A combination of crawling and undulation gaits allowed this robot to navigate a difficult obstacle. This demonstration illustrates an advantage of soft robotics: They are systems in which simple types of actuation produce complex motion.

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Nov 28, 2011
Really cool engineering,
but still totally creepy.

Nov 29, 2011
now if the researchers could bring it down to the size of a grain of pepper or smaller, it might be useful in delicate brain surgery where a steady hand might not be steady enough to extract a tumor.

For that kind of thing we already have robot assisted surgery where the robotic hand is (passively) guided by the operator and an algorithm automatically smoothes out any tremors.

What they should so is combine the gas filled chambers with liquid filled ones (like in living organisms). Would give added strength to the structure.

Nov 29, 2011
Interesting concept. Like a robotic amoeba. Starfish would be neat too.

Anybody working on artificial muscles based on cross-linked polymers ?

Nov 29, 2011
Anybody working on artificial muscles based on cross-linked polymers ?

These guys are:

Electroactive polymers:

Nov 29, 2011
....hmmm.....seen those. Seen anything nifty with IPMC's ?

I recently started fooling around with CL polymers, somehow managed to make one that eerily resembles muscle tissue, got me to thinking about what other materials I could play around with this winter ....o,O

Nov 29, 2011
I love how he, after the walk, splat himself where he stands. Reminds me of.. well.. me. :D

Nov 29, 2011
If the surgeons had a small enough unit to remove the rest of the malignant cells,

That's not really an issue in brain surgery. The problem lies more in the fact that you can't readily distinguish malignant from benign cells. Tumor surgeries usually try to take out a bit more - just to be safe. In brain surgery that line has to be drawn somewhat tighter as just 'taking out an extra scoop' is not really an option. tumors often also frazzle out out the edges - making the delineation doubly difficult (these outliers often don't even show up on scans).

Then you have to consider that removing a tumor does not neccessarily remove the cause of the tumor (which may be genetic, trophic, or the tumor you removed my simply be a secondary one that was spawned by a tumor somewhere else). So reappearance of a tumor is not always caused by suboptimal removal of the first one.

Nov 29, 2011
Pirouette, you looking at this and claiming it would be useful for brain surgery is about as logical as someone claiming the same for an automobile. Sure if an automobile were small enough we could drive it around someone's arteries... jeez. How can you not see that creating something of such a small size, not the form, is the problem. Uggggggggggggggggg.

Maybe if we can get you to realize your nuttiness on an issue you aren't so involved in maybe you'll be capable of some self reflection.

Nov 29, 2011
Yeah, and a nano-Humvee with roof-mounted ablative lasers would also save countless lives.

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