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Artificial Muscles Pack a Mean Punch
sciencehabit writes "Here's a twist: Scientists have designed a flexible, yarn-like artificial muscle that can also pack a punch. It can contract in 25 milliseconds—a fraction of the time it takes to blink an eye—and can generate power 85 times as great as a similarly sized human muscle. The new muscles are made of carbon nanotubes filled with paraffin wax that can twist or stretch in response to heat or electricity. When the temperature rises, the wax melts and forces the nanotubes to contract. Such artificial muscles, the researchers say, could power smart materials, sensors, robots, and even devices inside the human body."
Does that mean getting rid of waste heat is going to be even more important?
What's the efficiency like?
I wonder if such a technology could be used in artificially enhancing the muscles of a person to make a super-human, or super-soldier. The chemistry can't be that complex, so I'm sure it's possible through bio-chemical engineering. I'd bet $100 that the US and others have done it before.
Sig: I stole this sig.
Could be interesting. But what's the energy conversion efficiency like?
Have gnu, will travel.
I never asked for this...
On top of the power efficiency I'm also wondering how many times a muscle can be used before it gets too damaged.
That article doesn't answer the most important question: how much essence does it cost?
augmented that.
Reserve your super suit now!
Ah. Excellent, I have been intentionally not developing real muscles for years so I would have room for the artificial ones.
Who's sorry now dad?!
Watch out for CANDLE MAN!
What I'm curious about is what kind of stress this would introduce to a human body if it it were used for artificial limbs. 85 times the strength would also mean a similar increase in energy conversion. Sure, It would be super sweet to see someone do the long jump without a pole, But at the same time the laws of physics haven't changed. The impact will still be distributed through out the skeletal structure of your body. Unless there is some type of hydraulic impact system. Then, Well, I admit defeat on that one! :p
Jack Vance had something like this in one of his stories. Science fiction becomes fact once again. (Now where's my hovercar)
http://www.sciencemag.org/content/338/6109/928.full
I suppose that this will answer some of the questions.
Kind of makes me wonder why slashdot almost never links the REAL articles and instead just links some fancy news sites with second hand information.
Yam-like? Or is that just bad keming?
Heinlein would have wanted Rasczak's Roughnecks to have 85 times normal strength for their exoskeletons. Still need some pocket nukes though. And some giant bugs to kill.
Maximum SPEED!
Maximum STRENGTH!
and [obligatory]
FALLLLCONNNN PUNNNNNNNCHHH!!
I remember reading some article about 15 years ago, where they talked about getting carbon nanotubes to contract quantum mechanically using an ionic solution. I think that contraction was even stronger than this stuff from the article.
These would make for a kick-ass revival of the old Rock'em Sock'em Robots toy!
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
So the sex droid has super impressive kegel muscles but cooks wieners in ten seconds flat!
I said - don't look Ethel!..., but it was too late..., she'd already looked.
FALCON PUNCH!!!
I deny that I have not avoided attaining the opposite of that which I do not want.
If you eat a ton of Halloween candy and then grill out on a charcoal grill, it's basically the same thing. You'll get mega super mutant muscle strength!*
*this statement has not been approved by the FDA
Could we run a belt made out of this stuff over a pulley system and apply a temperature differential along its length and get a motor? It's unlikely to be efficient as long as it's temperature driven, but what if the filler material is instead responsive to electricity?
Perfect for that cow zombie apocalypse! Also, wax on - wax off.
Kind of makes me wonder why slashdot almost never links the REAL articles and instead just links some fancy news sites with second hand information.
Maybe because of the paywall?
Sadly like it stated, the fiber is only useful as higher temperatures. Mostly because of the Latent temperatures at witch wax changes state. Though the most discerning thing, is most artificial items will never make it into practical use.
The major reason being the body is reproductive and self maintaining if given the right fuel and resources, along with that it is also adaptive to be (to en extent) anti disruptive. Meaning we function the same in a various amount of conditions. While artificial stuff will work its area will be limited to even more specific conditions and higher maintenance that we could ever keep up with. So a artificial human or android is highly impractical due to natural wear and tear.
Also it may be 1e5 times stronger but just how efficient is it in terms of cost of production and heat consumption to maintain its positions. Also at the speed it can move, how long it the durability and ability to repeat that effectively.
Contract in 25 mS - what does that mean? The time before contraction is initiated? Or is it related to shortening velocity? If so, over what distance and how liner is the contractile force? Then there's recovery time before the next contraction; the force generated per unit cross sectional area of this material (what do they exactly mean by "size"); efficiency and heat dissipation. As with all these hyped technology claims that purport to mimic biological systems there's an embarrassing lack of detail. And optimistic expectations for attracting venture capital I imagine. I'm very skeptical this would compete with mammalian or avian skeletal muscle on any number of important functional parameters. If it did and it was mine, I would be shouting the numbers from the rooftops.
This seems to have the same problem as shape-memory alloys. Those change shape quickly when heated above their transition temperature, but the amount of energy you have to put in is far more than you get out. Then they have to cool down before they can be cycled again. Power to weight ratio is good, but energy to weight ratio is poor because the cycle time is slow.
Probably not all that useful as a general actuator.
Also important and that no one has mentioned yet is the contraction ratio. The muscle does no good if it can only contract 1% of it's length...
The article's (Electrically, Chemically, and Photonically Powered Torsional and Tensile Actuation of Hybrid Carbon Nanotube Yarn Muscles) abstract has this to say about how many times this Nanotube yarn muscle can be used:
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We have designed guest-filled, twist-spun carbon nanotube yarns as electrolyte-free muscles that provide fast, high-force, large-stroke torsional and tensile actuation. More than a million torsional and tensile actuation cycles are demonstrated, wherein a muscle spins a rotor at an average 11,500 revolutions/minute or delivers 3% tensile contraction at 1200 cycles/minute.
[bold text added by me to accentuate the answer, at least one million cycles demonstrated thus far]
Sulphur, I don't have access through the paywall to the article, but I calculate the fiber recharge time to be less than 50 milliseconds:
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"delivers 3% tensile contraction at 1200 cycles/minute"
The abstract explicitly states that they tested the carbon-nanotube fibers for up to 1-million cycles with a rep-rate of 1200 cycles/minute, so that gives us 20 Hz, so the recharge/rep time is less than 1/20th of a second = 50 milliseconds:
The article's abstract (Electrically, Chemically, and Photonically Powered Torsional and Tensile Actuation of Hybrid Carbon Nanotube Yarn Muscles) has this to say about how many times this Nanotube yarn muscle can be used:
.
We have designed guest-filled, twist-spun carbon nanotube yarns as electrolyte-free muscles that provide fast, high-force, large-stroke torsional and tensile actuation. More than a million torsional and tensile actuation cycles are demonstrated, wherein a muscle spins a rotor at an average 11,500 revolutions/minute or delivers 3% tensile contraction at 1200 cycles/minute. [bold text added by me to accentuate the answer, at least one million cycles demonstrated thus far]
... More than a million torsional and tensile actuation cycles are demonstrated, wherein a muscle spins a rotor at an average 11,500 revolutions/minute or delivers 3% tensile contraction at 1200 cycles/minute.
That may be good for some muscles, but think about all the little movements you do when handwriting. Some muscles get to do many cycles just writing a little piece of text. And it's not like we really keep our body parts steady with muscles either contracted or relaxed.
I'm not a doctor but I think we need to know how much cycles regular muscles perform in a given time period, this would shed light if this is useful for any kind of human surgery.
Well, think of the eyelids blinking (skeletal muscle) or of the human heart (cardiac muscle). The heart beats on average of say 60 times per minute (1 Hz) for a life-time in the USA of 77 years:
60 beats/min * 60 min/hr * 24 hr/day * 365.25 days/year * 77 years
= 2429935200
= 2.43 * 10^9 = 2.43 billion heartbeats per average lifetime.
.
So if you're 31 years old, your heart have beaten 10^9 times thus far. Then each muscle you use at a lower rate than the heart would tell you that you need fewer than 2.43 billion reps to make it last a life-time.
The sky above the harbour does have the color of a TV set turned on a dead channel, today.
Oh, the beautiful gloss of greality!
...just heat them up.
My god!!! I can actually realise my dream and become Bionic!!
One million cycles at 1200 cycles/minute means that it breaks in 13.8 hours.
jamstar7 wrote: "85x stronger muscles are going to do some serious damage if the bones aren't reinforced."
From TFA, suggested initial applications include "precise facial expression in robots" and "movement in small toys like robotic fish":
"Compared to their size and weight, the performance of these muscles is spectacular," Baughman says. "And we can do all sorts of things with them: We can weave them; we can braid them; we can knit them; we can cut them in different lengths."
Baughman suggests that the muscles could be useful for providing power for microfluidics chips, generating precise facial expressions in robots, and providing movement in small toys such as robotic fish in an aquarium. For many other applications—such as those inside the human body and "smart fabrics" that could become more porous when the temperature heats up or contract around an open wound—the muscles will need to be improved and scaled up in size.
It is an interesting approach, but we're a ways off from powered armor or super-strong robots.
Now figure out a way to mass produce it and slap it on a robot.
Or make a new artificial heart.
I appreciate that this is a first step. But sometimes I get tired of the "scientists in a lab figured out a way to make a few molecules/micrograms/reallyreallytinyinsignificantamounts of X after 1000 hours of labor". I'm much more interested in the practicality of things, and until you can efficiently mass produce in usable quatities i almost (not quite though) dont care. yes i am impatient.
The guy who said the election was rigged won the presidency with the second-most votes.
That doesn't say whether they tested to the breaking point or to 0.001% of its lifespan. 1 million contractions is a small amount for many muscles. About 12 days for the heart.
while(1) attack(People.Sandy);
Most things would break in a relatively short timeframe if operated at their maximum rate. A human heart would expend it's average lifetime beat count in a little more than 3 years if it operated at 1200 bpm and only 22 years at 200bpm(target max rate for a human heart).
Consider an RF electro-mechanical switch. They tend to be pretty robust (as far as mechanical items go), but you won't see many manufacturers list a life of greater than 1,000,000 cycles. Thats on a very simple, highly mature design. So a device which has been in high volume manufacture since the 60s, is a highly competitive market and thus manufacturers would do well to improve the design, and it is a component which is a single point of failure by virtue of the fact that it is in-line with the RF path (in most configurations) so a failed RF switch often means the entire system (or systems) depending on it fail (or are at least degraded). As you can see, increasing the cycle count for these things is HUGE selling point, yet again, we only see a 1M cycle count advertised on a mature design.
1 million cycles on a new technology is actually pretty damned impressive. I certainly wouldn't use it in a heart replacement yet, but almost any other muscle in the human body would certainly be able to support a 1 million cycle lifetime (assumptions that most other muscle replacements would be accessible and replaceable in event of a failure or would be controlled in a manner to minimize extraneous movements and thus wasted cycles)
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
I canget rid of these flash limbs and get 'bionic' arms, and legs.
The Kruger Dunning explains most post on
1200 cycles per minute isn't the maximum. It's the frequency needed to exert 3% tension.
Give me Classic Slashdot or give me death!
Provided these synthetic nano-muscles are energy efficient, they sound like something that would work well for really tiny insect sized robots. Tiny magnet based motors appear to have some power/efficiency limitations because of the nature how magnets themselves scale, so something like this may be very beneficial to itty-bitty robots. If these don't need much juice for the mechanical impulse they can provide, that R/C dragonfly might fly for an hour instead of under 10 minutes. It's also likely many tiny mechanisms may be able to get rid of reduction gearing too, provided these synth-muscles produce that much more force, which then saves on weight and allows for further miniaturization.
...or you'll be able to break those bones into itty-bitty pieces. Even as it is, bone and cartilage often have to withstand muscular forces that are ten to thirty times greater than the limb itself is actually exerting due to mechanical disadvantage at the torque pivots.
Multiply that by 25 and you'll very likely exert fracture-level stresses on the bone or severely damage the cartilage. So if you plan to "go bionic" either use scaled down versions of these "muscles" or go bionic all the way with adamantium bones.
With that said, it's still kind of cool...
rgb
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
If it can only contract once, then it won't be very useful.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Human have relatively weak muscles so the "85 times" figure doesn't ring a bell. How long lasting are these artificial muscles? I would imagine rotation is something that will wear out more quickly than the current "solution" for human muscles.
ARGH!
Seriously, a few things to consider are
1) replacing natural muscle with this artificial muscle means that your energy requirements are drastically reduced: the ATP requirements would probably be limited to the nerve impulses required for muscle contraction and some other collateral factors.
2) you would need to have some sort of aesthetic implants: the amount of artificial muscle required to replace is going to be smaller: "[artificial muscle] can generate power 85 times as great as a similarly sized human muscle". Otherwise, you have freaky skeleton dudes walking around.
3) You to create some kind of feedback sensor so you don't tear up tendon and ligament
3a) The skeletal system and connective tissues need to be enhanced to account for higher load.
Just don't fly too close to the sun!
Such a material could be used to create supersonic pellet launchers.
Can we call it a human revolution?
Nice idea, but would mean a whole lot more if they could fix this stupid Thomsen's Disease that I have.
Then again, I never expect that to happen in my lifetime!