Soft, bendy robots could have a wide variety of benefits, from squishing into tight spaces to conduct surveillance, to crawling through a person's body to deliver drugs or take medical images. But it's hard to build entirely soft objects containing soft bodies, soft batteries and soft motors. A new version developed at MIT and Harvard is both soft and tough, inching around like an earthworm yet surviving multiple cruel blows from a rubber mallet.
The robot is nicknamed "Meshworm," after the earthworms that inspired its design. Rather than using liquid, air or silicone gears to get around, like other soft robots we've seen, Meshbot uses artificial muscle made from a shape-memory alloy. It looks very much like a squiggling worm, as you can see in the video below.
Researchers led by MIT mechanical engineering professor Sangbae Kim took a flexible mesh tube and encircled it in wires out of titanium and nickel, an alloy that contracts and expands with heat. They separated the wire into segments, much like those found in an earthworm, and applied a current to heat some of the segments. This made Meshworm's soft body squeeze together sections at a time, which caused it to inch along a surface. This type of locomotion is called peristalsis, and it's the same action used by snails, cucumbers and our own gastrointestinal tracts (to move food into our stomachs).
The team examined earthworm body structure to come up with this idea, and found that earthworms use latitudinal and longitudinal muscle groups to inch themselves along. The mesh tube represents the longitudinal section, and the shape-memory alloy represents the horizontal muscle group.
The best part may be the robot's durability. There are no pneumatic pumps, rigid gears or batteries to break, so the robot can survive all kinds of assaults. This could make it useful for military applications — DARPA funded this research. Kim and colleagues subjected the robot to a battery of tests to see how it held up, including smashing it with a mallet and stepping on it.
"You can throw it, and it won't collapse," Kim says. "Most mechanical parts are rigid and fragile at small scale, but the parts in Meshworms are all fibrous and flexible. The muscles are soft, and the body is soft … we're starting to show some body-morphing capability."
The team recently published details of the design in the journal IEEE/ASME Transactions on Mechatronics.
[via MIT News]
So why wouldn't you use that memory material in large layers to build muscle around skeletons just like in animals?
IBM BLUE + NSA+SKYNET + MILITARY INCH WORM = DUNE GONE VERY VERY BAD! Mmmm, lets unleash this little critter in IRAN, lol.
... Endoscopes? Because *that* would be comfortable o_o
I'm talking robotic skeletons not human skeletons, though, there could be some interesting possibilities with that too...
Well I think you need to ask things like how efficient is this vs servos, hydraulics and pneumatics. Would this muscle be better to use than current means to move large scale robotics? seems to me like it really only fits well with small scale robotics. If it uses temperature, than I am sure your performance may be limited to how fast you can heat and cool your "muscle"
popsci, please note that it's 'sea cucumbers'. I was having a little trouble visualizing packs of angry cucumbers creeping up to my house.
@FlyBoy83, small scale is more what I'm referring to and the precision needed. There is a block in that field due to the size of motors versus the strength needed which defeats many of the uses of small robots. Also, there is a need for more complex fluid motion which this material looks like it could solve.
The temperature limit may not be too bad considering a thin filament will heat up rapidly under electric load but I don't know what could be done for rapid cooling.
Phoenixamaranth, Agreed I see a a huge benefit for complex fluid motion, also heating a thin filament doesn't take much and perhaps if the device was intended to navigate through the human body than bodily fluids could assist with cooling. I'm sure this is a fantastic stepping stone for the right minds to advance it toward what we all imagine or hope for.
it'd be better if we could scale it down to maybe the size of muscle fibers or at least muscle bundles. it'd be even better if we could design a suit that basically added an entire muscle group to key locations on our body!
to mars or bust!