Researchers Build Wearable Generators

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Researchers Build Wearable Generators

Posted by samzenpus on Sunday April 10, 2011 @07:34AM from the power-from-the-people dept.

schliz writes "From the itnews article: 'Bioengineers from the University of Auckland have developed cheap, lightweight rubber power generators that could harvest up to a Watt of power if embedded in shoes. The researchers built on "dielectric elastomer generator" technology that used the movements of a flexible, non-conductive material to build up charge in attached electrodes.'"

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Help power cars? by froggymana · 2011-04-10 07:40 · Score: 2, Interesting

I wonder if something like this could be embedded in the tires of a car to help generate electricity to power it self. Would it actually be able to generate enough electricity to make it worthwhile for an electric car though?

--
"To prevent this day from getting any worse, I'll just read ERROR as GOOD THING" 1GJU8xLuDKDxEs4KLf8fAGyptoDsqvEsBT
1. Re:Help power cars? by QBasicer · 2011-04-10 07:45 · Score: 4, Insightful
  
  I wonder if something like this could be embedded in the tires of a car to help generate electricity to power it self. Would it actually be able to generate enough electricity to make it worthwhile for an electric car though?
  Unfortunately, the extra energy you'd get out of the generators would be provided by the engine (conservation of energy). You'd only get a benefit if the car was coasting downhill by turning the potential energy into electric energy. Since energy conversion isn't 100% efficient, you'd actually lose energy and be further behind in the process.
  
  --
  x86, oh yes, I'm pro.
2. Re:Help power cars? by WrongSizeGlass · 2011-04-10 07:47 · Score: 2
  
  These could be placed in the shoes of the secret service men who run along the President's car. Finally, a president who drives a hybrid!
3. Re:Help power cars? by westlake · 2011-04-10 08:10 · Score: 1
  
  You'd only get a benefit if the car was coasting downhill by turning the potential energy into electric energy.
  If you are coasting downhill, it seems to me that what you really need is power for the steering and the brakes.
4. Re:Help power cars? by Phoshi · 2011-04-10 08:20 · Score: 1
  
  Surely it does - when the tire un-deforms as it's coming off the road. There's not much 'wasted' kinetic energy in a car.
5. Re:Help power cars? by bmo · 2011-04-10 08:28 · Score: 5, Funny
  
  What we need is to find a way to coast uphill without having to coast downhill.
  I've got it.
  Put a magnet on the end of a pole in front of the car. It'll pull itself up a hill!
  http://27.media.tumblr.com/tumblr_laxcr841Fm1qewll0o1_500.jpg
  --
  BMO
6. Re:Help power cars? by oliverthered · 2011-04-10 08:28 · Score: 1
  
  one would assume that any energy created would create some drag co-efficient somewhere.. may act to cool the tires a bit though.
  
  --
  thank God the internet isn't a human right.
7. Re:Help power cars? by Anonymous Coward · 2011-04-10 08:56 · Score: 1
  
  For cars there is already something similar, at least in F1. KERS: http://en.wikipedia.org/wiki/KERS
  It has a questionable benefit for road cars though, considering the difference in forces.
8. Re:Help power cars? by arielCo · 2011-04-10 09:00 · Score: 1
  
  Touch the tires after a ride - they're hot from the energy wasted in this deformation-restoration cycle.
  
  --
  This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
9. Re:Help power cars? by QBasicer · 2011-04-10 09:00 · Score: 1
  
  Unless you used that energy to recharge some capacitors or batteries or something useful. Even if that power went into the electrical system directly there'd be less of a demand on the engine and thusly use less fuel.
  
  --
  x86, oh yes, I'm pro.
10. Re:Help power cars? by Anonymous Coward · 2011-04-10 09:05 · Score: 1
  
  What we need is to find a way to coast uphill without having to coast downhill.
  My grandfather walked to school uphill both ways. And it was always snowing.
  I suggest we look for the opposite of this area, perhaps on the other side of the world, and then we all can start coasting downhill on all our errands we go and it will always be nice and sunny:)
11. Re:Help power cars? by hedwards · 2011-04-10 09:10 · Score: 1
  
  Well, at least we can still use windmills to keep the Dutch cool.
12. Re:Help power cars? by Unoriginal_Nickname · 2011-04-10 09:10 · Score: 2
  
  They're hot from friction with the road.
13. Re:Help power cars? by arielCo · 2011-04-10 09:12 · Score: 1
  
  If you meant "to power itself" literally:
  The extra energy generated from the tires would have to come at no cost from the engine. That is known as a perpetual motion machine, which violates the principle of conservation of energy (free lunch out of nowhere).
  Now, if you meant "have some extra power for accessories and the like":
  When tires roll they get hot, partly from the energy wasted flexing and un-flexing the rubber, which is not perfectly resilient. Any energy drawn out of this cycle would ultimately be supplied by the engine in addition to said losses, which is the same as drawing current from the alternator minus the conversion losses of the elastomer.
  OTOH, brakes as implemented in most vehicles dissipate engine energy, and that's where regenerative brakes may be the answer, once they're practical
  
  --
  This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
14. Re:Help power cars? by modmans2ndcoming · 2011-04-10 09:53 · Score: 1
  
  The rubber in the tires is compressing anyway. unless this generating material is more flexible than car tire material, then I see it as capturing energy that would be lost with out it.
15. Re:Help power cars? by SeaFox · 2011-04-10 10:04 · Score: 1
  
  Damn you! I saw that same pic once and saved it thinking "This will come in handy someday, on Slashdot most likely".
16. Re:Help power cars? by arielCo · 2011-04-10 10:23 · Score: 1
  
  I'm saying that they do, and any usable energy you want to harvest at the tires (as from using these dielectric polymers) will be in addition to this heat, and thus will have to be supplied ultimately by the engine. At any rate, we're talking single-digit watts here, tens at most, when the engine puts out tens of kW.
  Energy harvesting is mostly about energy sources that are already present and end up as heat (sea/river waves, wind, sun), or "stealing" a few watts from a system you can't modify (e.g. your body). The idea of using human gait has been around for a whlle, and it can be a bit tiresome because in each step some of the energy that your tendons recover is being diverted to the device, so the goal is to increase conversion efficiency.
  There are MUCH bigger sources of recoverable energy, including regenerative brakes (last paragraph).
  
  --
  This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
17. Re:Help power cars? by TheClam · 2011-04-10 11:00 · Score: 1
  
  No, they're not, unless you've been drifting.
  The friction between the tires and the road is static friction, which keeps the tire from slipping. Only kinetic friction would result in loss of energy as heat.
18. Re:Help power cars? by TheClam · 2011-04-10 13:23 · Score: 1
  
  Windmills do not work that way.
19. Re:Help power cars? by michelcolman · 2011-04-10 22:39 · Score: 2
  
  Depends on your definition of "slip". If you say a tire is slipping when its rotational speed does not match the theoretical zero-slip speed of a rolling tyre (which is a common definition), then yes, it is slipping pretty much constantly while driving. However, this "slip" is comparable to your being able to move your finger forward and backward while touching something, without the finger actually sliding over the surface, just using the elasticity in your fingertip. A tyre can keep doing this as it rolls around, which means the calculated "slip" is not really the tire sliding over the surface, but rather a continuously repeated deformation of the tyre surface which can give a significant difference between the theoretical zero-slip speed and the actual tire rotation speed. So while it is slipping according to the naive definition "speed does not match", it is usually not slipping when you use the "sliding, screeching" definition. That only happens in tight turns or when you drive like I do ;-)
  This deformation-pseudo-slip does generate some heat since rubber does not reversibly deform perfectly without energy loss, but this is nowhere near the amount of energy released in a "real" slip.
20. Re:Help power cars? by Wolvenhaven · 2011-04-11 00:16 · Score: 1
  
  What about embedding it in the road itself? Roads flex from cars driving over them, if this stuff could be made cheaply, laying down sheets of it under the road surface might generate a lot of power. If a person walking generates a single watt, thousands of cars weighing thousands of pounds theoretically would produce an exponential increase on that. Power transport would be an issue over this type of design, but it could be done every few miles so it generates just enough power to power the street lights, traffic lights, and stuff of that nature and maybe a small surrounding area too if the power generation is high enough. On certain roads it would also be more reliable than solar/wind power as there is always a base-number of cars driving on the road at any one time.
  
  --
  Orwell was an optimist.
Up to a Watt of power by Anonymous Coward · 2011-04-10 07:41 · Score: 1

Bioengineers from the University of Auckland have developed cheap, lightweight rubber power generators that could harvest up to a Watt of power if embedded in shoes.
One watt and then if you want another watt you have to buy some more shoes? I can't see it catching on.
1. Re:Up to a Watt of power by bemymonkey · 2011-04-10 08:38 · Score: 4, Interesting
  
  A watt can recharge an entire smartphone battery in 1-2 hours... I'd welcome a pair of shoes that provides me with a Watt of power when I walk around.
2. Re:Up to a Watt of power by TD-Linux · 2011-04-10 10:08 · Score: 3, Insightful
  
  One watt and then if you want another watt you have to buy some more shoes? I can't see it catching on.
  A watt is a unit of power, not energy. The lifetime of the shoes is unspecified. Speaking of a watt, that's a lot of power for an energy harvester like this, and sounds too good to be true - because it is. The article only shows a 10mW generator, though that is still enough for periodic radio transmissions. Also, I would guess because it is electrostatic in operation, it would also work as a fairly large capacitor for temporarily storing the energy.
3. Re:Up to a Watt of power by Simon80 · 2011-04-10 13:14 · Score: 1
  
  I wish you were right, but if you take a 1500mAH battery at 3.7V, and assume 100% efficiency in charging, it's more like 5 and a half hours, and I'm guessing that's not a valid assumption.
4. Re:Up to a Watt of power by bemymonkey · 2011-04-10 17:12 · Score: 1
  
  Ah crap, you're right... for some reason I was going Watts=>Amps at 1:1 - *facepalm*.
  Ouch.
  It would charge, just slowly - or keep the battery from draining when in use. 1W (~270mA) is around the average amount my Desire draws in active use (screen on low brightness, online via 3G)...
5. Re:Up to a Watt of power by michelcolman · 2011-04-10 23:06 · Score: 1
  
  As long as you keep pacing while on the phone, it could work.
6. Re:Up to a Watt of power by bemymonkey · 2011-04-11 00:02 · Score: 1
  
  Funnily enough, I actually do that - drives my girlfriend crazy.
Great by Anonymous Coward · 2011-04-10 07:41 · Score: 1

Now all I need are 2,000 people jogging around my house and I'm set.
Obvious statement by 1s44c · 2011-04-10 07:59 · Score: 2

If you wear these walking will become 1 watt harder.
1. Re:Obvious statement by hedwards · 2011-04-10 09:12 · Score: 1
  
  Not really most people bounce a bit when they walk, and the knees end up having to absorb the wasted energy, may as well absorb at least some of it and put it to good use.
2. Re:Obvious statement by White+Flame · 2011-04-10 11:26 · Score: 1
  
  The only real sensible non-intrusive human power generation I've seen was based on catching your knee joint as it extended to take the next step.
  Normally when you extend your leg out, your muscles "catch" your lower leg so you don't snap it out against the joint's limit. By having a device hinged on your knee to slow your shin down instead, you do only half of that cycle of work, and also generate some electrical power at the same time.
3. Re:Obvious statement by wamatt · 2011-04-10 19:28 · Score: 1
  
  Not obvious.
  Because it may reduce heat / sound energy emanating from your shoe by 1Watt.
4. Re:Obvious statement by StillNeedMoreCoffee · 2011-04-11 03:10 · Score: 1
  
  That is true, no free energy. Like walking on sand. Each step would expend more energy, that is unless it is taking over a normal function of the shoe that was disapating that much energy in heat, sound, wear. If that is the case then it could be that the walking will not be any harder.
5. Re:Obvious statement by 1s44c · 2011-04-11 22:13 · Score: 1
  
  Not obvious.
  Because it may reduce heat / sound energy emanating from your shoe by 1Watt.
  Things can be obvious even if they are not true.
Been hearing this for a while now by Trepidity · 2011-04-10 08:05 · Score: 5, Informative

This might be a new advance, but it's hard to tell. Here is a Slashdot story from 2001 with basically the same "researchers find a way to make shoes generate power" line.

--
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
1. Re:Been hearing this for a while now by Anonymous Coward · 2011-04-10 08:22 · Score: 1
  
  We can call this an advance purely because of the numbers they're reporting--according to the 2001 article. While then they reported 0.0013W generated, now we're seeing one whole watt. Quite the improvement, and it can actually be used for things!
2. Re:Been hearing this for a while now by Hultis · 2011-04-10 08:24 · Score: 1
  
  So, would these shoes be sole-ar powered?
  
  That one made me laugh, thanks kafka93 (ten years later)!
3. Re:Been hearing this for a while now by binkzz · 2011-04-10 08:26 · Score: 1
  
  Maybe they got lost in time, and have been trying to get together 1.21 billion Chinese people to wear these shoes so they can get back.
  Just a thought..
  
  --
  'For we walk by faith, not by sight.' II Corinthians 5:7
4. Re:Been hearing this for a while now by BillX · 2011-04-11 15:10 · Score: 1
  
  Haha... The company I work at bought the company (that bought the company...) that used to make those! While they existed, they used to make vibration-absorbing golf clubs and bike shocks with the same guts.
  It was a clever idea, at least - inside were one or more piezoceramic benders, wired through a very large inductor to a load (typically an LED to show that it was Doing Something). For the spark chasers out there, it was an LC tank circuit tuned to cancel out the main resonant mode of the "beam" (ski, club shaft), using the loaded piezo to draw mechanical energy out of the system (similar to back EMF on a heavily loaded electric motor). And it did "work"; at least in a laboratory setting, vibration was measurably dampened. Whether the difference was enough to matter in practice was debatable, though.
  The big problem was that for as "active" as it was, it was completely passive - the only motion-opposing force was provided by what electricity was extracted from the motion itself (some 10s of mW per strike). Its downfall AFAICT was that a passive tuned mass damper could achieve the same result for 1/10 the cost. K2 / ACX eventually folded and was bought mostly for its equipment. Those same machines now are used make piezo energy harvesters that use vibrations to power small sensors embedded into airframes and other hard-to-reach places.
  
  --
  Caveat Emptor is not a business model.
This is useless, but... by bmo · 2011-04-10 08:14 · Score: 2

...it's perfect for a gag.
Hook this up to a pack of capacitors and I can go 'round zapping people, at random, without any need to find any woolen carpets to shuffle my feet across.
"Hi, Bob, that's a nice tray of cmos chips ya got there." *zap*
--
BMO
1. Re:This is useless, but... by yelvington · 2011-04-10 08:15 · Score: 1
  
  Or rig the capacitors to discharge back into the shoe. Perpetual motion!
Olympics by Flipstylee · 2011-04-10 08:27 · Score: 2

Perhaps with enough of these the olympics could power itself...
Done before by jimmydevice · 2011-04-10 08:40 · Score: 1

This idea was thought up in the 70's, and probably long before that.
years away from being wearable... by StudCapsFTW · 2011-04-10 09:00 · Score: 1

The title is misleading. From TFA: “What we want to work towards is something that’s wearable ... but that might be a few years away yet.”
SWEET! by Lexible · 2011-04-10 09:02 · Score: 1

Regenerative breaking for people!
Next, they'll be... by ToastedSpider · 2011-04-10 09:19 · Score: 2

inventing stillsuits. Add a bit of spice and we're set!
Soylent Shoes by Anonymous Coward · 2011-04-10 09:32 · Score: 1

Regenerative breaking is people!
Re:Power generating rubbers? by Culture20 · 2011-04-10 09:34 · Score: 1

...think of the possibilities.
It sits in my wallet for two decades and goes bad?
I'm Siiiiingin' in the Rain... by Ezekiel68 · 2011-04-10 09:40 · Score: 1

[BZZZZzzzzzzzt!] GAaaaaaaaaaAAaAaaAAh!

--
Imagination is more important than knowledge -Einstien
Bouncing Breasts -- energy by psychogre · 2011-04-10 09:59 · Score: 1

Old news, but personal power generation has been around for quite a while.
See http://www.slate.com/id/2193827/
Walking? by Adam+Appel · 2011-04-10 10:08 · Score: 1

For this to work in any way we would have to get people walking somewhere.

--
They come in the dark, only in the darkest.
Re:Slashdotters need not apply by White+Flame · 2011-04-10 11:27 · Score: 1

Hey, I bounce my leg all the time, you insensitive clod!
Water... by ibsteve2u · 2011-04-10 15:59 · Score: 1

Could see setting ribbons of the things fluttering in ocean currents and rivers...somewhat less harmful to the fish, I reckon; they've dealt with fluttering seaweed a lot longer than they have turbine blades.

--
Orwell: "In a Time of Universal Deceit, telling the Truth is a Revolutionary Act"
Your conversion might be off by LostMyBeaver · 2011-04-10 18:34 · Score: 1

After all, a Jiggawatt is clearly not a Gigawatt. It might be the old definition of a Gibiwatt prior to those nifty genii who came up with a power of two friendly version of the metric system. Of course, it could also be that Douglas Adams was involved with the script indirectly and it's somehow based on base 13.