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Toys Science Technology

The Ubiquitous LED Becomes More Ubiquitous 109

Posted by timothy from the more-meats-in-cones dept.
LiberalApplication writes "Piezoelectric generators have been mentioned here before, regarding the military's plan to integrate them into the heels of boots for the purposes of harvesting electricity from the cumulative stompage of a soldier, but now someone has come up with the idea to combine them with LEDs and cast the entire assembly into a little block of resin. Well, a stick, really. If you were getting tired of seeing little blinky lights everywhere, you ain't seen nothing yet."
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The Ubiquitous LED Becomes More Ubiquitous

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  • These things might make cool rave lights since they would glow so when people dance! And they wouldn't run out, so they would be reusable for the next event.

    But seriously, PiezoElectric power will likely be used as a parasitic power source for lots of small devices. Self-charging laptops [slashdot.org], Forever Flashlights [thinkgeek.com], etc. It might be the only way to power nanoscale devices [smalltimes.com] like found in The Diamond Age [slashdot.org]

    • Re:Lots of uses for Piezoelectric (Score:4, Interesting)

      by addaon ( 41825 ) <addaon+slashdot@nOsPAM.gmail.com> on Wednesday February 11, 2004 @02:00PM (#8251468)
      Score: 3, Interesting? Well, at least you didn't get an Informative. You have three links... one is to fiction, so we'll skip it. The two that are to real items have nothing at all to do, shockingly, with the point you're (failing at) making. Both use standard coil/magnet arrangements instead of piezo crystals. Have you ever thought about how much sound energy needs to be traveling through a piezo crystal to generate, say, 1W?
      • Have you ever thought about how much sound energy needs to be traveling through a piezo crystal to generate, say, 1W?

        Ummm, let me guess....

        One watt of sound?

        -
        • Well, at least you have thought about it. Basic principles of physics may escape you, but I admit, you lived up to my original standards.
          • Actually I have an exceptional understanding of physics. If you want a more rigorous analysis, then assumuing negligible energy loss to heat, and assuming an isolated piezo crystal (in a vacuum), then yes, 1 watt of sound energy will produce 1 watt of electricity. Maybe I have a peculiar sense of humor, but I thought my post was funny. On one level, the "what color was George Washington's white horse?" answer was pretty much correct. Ideally it always takes one watt of energy type-X to generate one watt of
      • All I know is that the people who drive past my apartment with their cars about ready to rattle apart from all the extreme bass are dissipating enough power to run a small city.

  • Bicycles... (Score:4, Interesting)

    by stefanlasiewski ( 63134 ) * <slashdot AT stefanco DOT com> on Wednesday February 11, 2004 @01:28PM (#8251078) Homepage Journal
    These things look small and light.

    I'd love to get a set of these and attach them to the spokes on my bicycle wheels. Swirly rainbow of light zooming across the dark.

    No driver could miss me then.

    • Re:Bicycles... (Score:4, Insightful)

      by Baron_Yam ( 643147 ) on Wednesday February 11, 2004 @01:33PM (#8251150)

      Actually, on a smooth road these wouldn't work; they require a cycle of compression and decompression to generate power - you'd want nice hard tires and a bumpy road to shake the suckers up.

      It would be interesting to know just how vigourously they need to be jostled to generate a given luminosity.

      • think of those annoying beads that went up and down the spokes as you were biking.. I guess this wouldnt work with sufficiently fast biking, but slow enough and with low enough friction, they will follow gravity, and hit the outside of the wheel on the bottom and the inside when the spoke is on the top. But yeah, any sped I'd be bikign I'd think centrifical (centrifugal?) force would keep them towards the rim.

        maybe on the pedals? A gentle rotation motion prolly wouldn't work would it.. Yes, I didn't re

      • Re: (Score:3, Interesting)

        by account_deleted ( 4530225 )
        Comment removed based on user account deletion

      • Re:Bicycles... (Score:5, Informative)

        by John Hasler ( 414242 ) on Wednesday February 11, 2004 @04:53PM (#8253496) Homepage
        The tension in each spoke varies cyclically as the wheel turns. Just put a piezoelectric generator in series with each spoke.

    • Re:Bicycles... (Score:5, Funny)

      by benploni ( 125649 ) on Wednesday February 11, 2004 @01:52PM (#8251365) Journal
      No driver could miss me then.


      Actually, I thought you'd rather want him to miss you :-)

    • Re:Bicycles... (Score:5, Interesting)

      by jarran ( 91204 ) on Wednesday February 11, 2004 @03:03PM (#8252190)
      Well, they need batteries, but you might be satisfied with Hokey Spokes [hokeyspokes.com]. They even communicate somehow and sync if you have several on one wheel.
    • Ummm... don't you want the drivers to miss you?

  • Cool! (Score:5, Interesting)

    by Deagol ( 323173 ) on Wednesday February 11, 2004 @01:29PM (#8251082) Homepage
    I think self-powered and self-contained light sources are really cool. I'd rather have a Glowring [gadgets.co.uk], but they can't be imported for resale in the US/Canada. Any enterprising folks across the pond wish to work out a deal and get me some? ;-)
    • I know this is slightly off-topic, but -- are you sure it's safe to have that amount of tritium dangling from your keys? Those things look pretty bloody bright... just don't stick your keychain in your pocket if you wanna have kids in the future ^_^

      • Re:[ot] tritium?!? (Score:5, Informative)

        by Deagol ( 323173 ) on Wednesday February 11, 2004 @02:12PM (#8251609) Homepage
        I did my homework. The radiation emmited by these things is about as low-power as you get (even in nature). If you ingest the stuff, however, better file your will in a month or two. The stuff reacts as normal hydrogen, and is diffused throught the food chains (hydrocarbons -- fats!) and water supplies. Contamination is the major problem. But I'm guessing the mercury & lead in my 19" CRT would be far worse upon disposal, as well as the PCBs in my PC.

        Sure, I wouldn't give one to my kids (which I'm done having, btw), but it's safe. What were those military lights called? Watchlights? Watchglasses? Whatever -- they were regarded as safe, I believe.

        • Re:[ot] tritium?!? (Score:5, Informative)

          by Anonymous Coward on Wednesday February 11, 2004 @06:47PM (#8254487)
          Disclaimer; I am a Physics Undergraduate & have just spent the day on a tour of JET, where they use tritium as a fuel to start a nuclear fusion reaction.

          Gaseous tritium is absolutely fine, it decays by beta emission - but the electron is so unenergetic that it can't even penetrate skin.

          However, if the tritium oxidises, it becomes heavy water which can get directly absorbed by one's lungs. In which case, it pases through the body after a few days in the standard way ;) In case of contamination by oxidised tritium, the radioactivity of the patient's urine is monitored, as beer is poured down their throat to 'flush the system out'.

          The safe dose for gaseous tritium is 10s of thousands of times higher than that for oxidised tritium; if you did crack one of those vials, I doubt much harm would come to you at all. Any tritium released into the atmosphere will quickly diffuse into space [also the reason why there's precious little atmospheric hydrogen]...

        • Re:[ot] tritium?!? (Score:5, Informative)

          by deglr6328 ( 150198 ) on Wednesday February 11, 2004 @07:58PM (#8255048)
          No need to worry, these are absolutely safe. Even if you break open the capsule containing the Tritium (3H) and ingest the whole lot, there will be no need to fill out a will. The amount of 3H in these devices is limited to less than 25 millicuries and at a committed effective dose [wpi.edu] of 64 millirem per mCi you could only possibly be exposed to a REM or 2 in the absolute worse case scenario. The yearly limit for radiation workers set by the DOE is 5 REM, so I think you will be OK!! :-)

    • Re:glowrings (Score:1, Informative)

      by Anonymous Coward
      They're called "location markers", but could probably be keychains in a pinch.

      http://www.ameriglo.net/pages/locationmarkers.ht ml

    • Re:Cool! (Score:2, Interesting)

      by vlm ( 69642 ) *
      you can buy a similar tritiated light from www.unitednuclear.com [unitednuclear.com] and they are in the USA.

      It uses the same traser trademark.

      I have a green one, it's encapsulated into a teardropped shaped lump of plastic. It's on my keyring and it's about as bright as my clock radio at night.

      I have no relation to www.unitednuclear.com other than being a happy customer.

    • Re:Cool! (Score:3, Informative)

      by Suidae ( 162977 )
      Those glow sticks are popular items on E-bay.

  • targets (Score:4, Funny)

    by TheSHAD0W ( 258774 ) on Wednesday February 11, 2004 @01:31PM (#8251120) Homepage
    Oh great, let's make our troopers into marching Xmas trees, why don't we? "Don't fire until you see the lights of their feet!"
    • I forgot to make a joke about a record number of court martials for people trying to get out of the army by getting shot in the foot.

  • Jurassic Park (Score:4, Interesting)

    by AtariAmarok ( 451306 ) on Wednesday February 11, 2004 @01:32PM (#8251125)
    but now someone has come up with the idea to combine them with LEDs and cast the entire assembly into a little block of resin

    63 million years from now, some huckster is going to have an amusement park featuring cloned glowing lights.

  • Embedded into sidewalks (Score:3, Interesting)

    by SandSpider ( 60727 ) on Wednesday February 11, 2004 @01:32PM (#8251129) Homepage Journal
    It might be interesting to embed these into the top of a sidewalk, then watch the sidewalk start glowing whenever someone walks on it, or whenever there are other vibrations in the area. Not necessarily useful, but interesting.

    =Brian

  • Blinking LEDs on Combat boots? (Score:4, Funny)

    by weeboo0104 ( 644849 ) on Wednesday February 11, 2004 @01:34PM (#8251166) Journal
    the military's plan to integrate them into the heels of boots

    I wonder if they will resemble these. [nordstrom.com]

  • Concerts... (Score:5, Interesting)

    by Bugaboo ( 266024 ) on Wednesday February 11, 2004 @01:35PM (#8251176)
    Am I the only one who thinks this would be a neat thing to embed in a clear drumstick and then use at concert?

    Hell, disperse the little ones in the crowd and turn the whole place into a giant pulsating light...

    • Re:Concerts... (Score:3, Interesting)

      by Deagol ( 323173 )
      How about embedded onto speaker assemblies? Different colors for different cone sizes (or whatever -- I'm no audiophile). Could be rather neat-looking, no?
    • Am I the only one who thinks this would be a neat thing to embed in a clear drumstick ...

      Hey, that's a pretty cool idea. While not on the drumline of my high-school marching band (I played trumpet in the brass line), I imagine such a thing would have been well-received during a half-time show.

      The frivolous uses of these little gizmos are almost unlimited. :)

    • Am I the only one who thinks this would be a neat thing to embed in a clear drumstick and then use at concert?

      Public announcement! You now have 1 year if you want US patent protection, and you are out of luck if you wanted international.

  • Children's Shoes (Score:1, Interesting)

    by Anonymous Coward
    You know, I've noticed glowing blinking lights embedded in children's shoes for years. Are those lights battery powered?

    • Re:Children's Shoes (Score:5, Informative)

      by netringer ( 319831 ) <maaddr-slashdot@@@yahoo...com> on Wednesday February 11, 2004 @01:57PM (#8251428) Journal
      You know, I've noticed glowing blinking lights embedded in children's shoes for years. Are those lights battery powered?
      Yes. There are button cells and switches embedded in the sole of the shoes.

      I thought of those when I first read the "in the heels of soldier's boots" in the story.

      Cops loved it when crime suspects wearing those hip shoes tried to sneak away into the night.

      • I saw that on an X-Files episode once, but does it actually happen in real life? And if so, where can I get adult-sized light up shoes?
        • I saw that on an X-Files episode once, but does it actually happen in real life? And if so, where can I get adult-sized light up shoes?
          IIRC, it was real story on Fark [fark.com]. I didn't find it with a google.

          Maybe it was in regards to Juvenile-offender-sized shoes.

  • No more "blackouts" (Score:4, Interesting)

    by siegesama ( 450116 ) on Wednesday February 11, 2004 @01:51PM (#8251354) Homepage

    These things (or rather, an application of ther technology) would make amazing emergency lighting in offices or homes. Heck, even in non-emergency situations. Perhaps a walkway with peizo-electric flagstones to power the lights along its path?

    I wonder how much power could be obtained from the highways and biways of America? All those cars racing over millions of little generators all day long should produce a pretty goo amount of electricity, I'd imagine. It would almost make up for the ridiculous cost of burning all those fossil fuels in the first place.

    • A: Interesting idea.

      B: You're kinda missing the whole "conservation of energy" thing. It could never come close to making up the difference.

      C: After reading the article, it's clear that converting vibration into current will never create a large ammount of electricity. It WILL create small ammounts just about anyplace, allowing electronics to go without a battery or powercord. Pizo in the road might for various sensors to be included into a kind of "smart streets" (as opposed to "street smarts"). The
    • All those cars racing over millions of little generators all day long should produce a pretty goo amount of electricity,

      Probably so, but the energy produced would never even come close to offsetting the price of the generators.

      Instead lets put windmills on top of all the cars, that way they can charge themselves while they drive down the highway! (*)

      (* Yes, I know, its a joke.)
    • I wonder how much power could be obtained from the highways and biways of America? All those cars racing over millions of little generators all day long should produce a pretty goo amount of electricity, I'd imagine.

      No, because the highway doesn't flex; the tires do. Since it doesn't move, there is no work done. There is a very small amount of heat imparted on the roadway, but not very much. OK, so maybe you make the highway segmented, and use the weight of the car? Ok, the car still has to climb up t

      • For the conservation laws to work the highway must flex in proportion to the applied load. Normally the deformation is both very small and elastic in nature. Occasionally, (think lots of slow moving trucks on a hot summer day), it is significant and permenant.
    • exit signs of this tupe (first graph) exist..
      search for Self-Luminous Exit Signs, they'vc been about for a few years in the USA

  • Lost in the translation? (Score:3, Insightful)

    by Hardwyred ( 71704 ) on Wednesday February 11, 2004 @01:55PM (#8251397) Homepage
    The article claims that the piezo generator can crank out up to 10amps! Is that right?
    • one tiny shake and BLAM! there goes your LED. I seriously doubt the piezo generator can create 10A; I think it was a typo.
    • If the amps are that high, voltage must be way low... but that would necessitate a transformer to get the LED to shine. Sounds wrong.

    • Re:Lost in the translation? (Score:4, Informative)

      by TheOnlyCoolTim ( 264997 ) <tim.bolbrock@nOspam.verizon.net> on Wednesday February 11, 2004 @02:27PM (#8251774)
      Probably 10 mA, which would be on the low end of where LEDs are generally rated.

      Tim
    • Is this the same effect you get with those electronic cigarette lighters that make a spark when you press down the button?

      You can get a nice healthy spark from those things, which probably has to have a good voltage to jump across the air like that, but the amperage must be pretty low or they'd be deadly =D
      • Actually, no... IIRC, both the amperage and the voltage are surprisingly high. The reason you don't get fried by the piezo-electric lighters or by simple static shocks is because the duration is incredibly short.
    • It would probably be a high peak current.

      As for the LED's: A LED might well be able to handle this much current. Although continous current should not exceed around 20 mA on most models, most LED's can handle short peak currents just fine.

      For a viewer, it would be difficult to spot the difference in a 1 ms 1 A flash and a 10 ms 100 mA flash.

      Recent LEDs have also been produced with phosphors in them to make specific colors (and white). These phosphors can also help to buffer the peak of energy and emit

      • Just as a data point, I attached a white light LED to a single motherboard-style lithium coin battery in September 2003. That LED is still glowing 5-1/2 months later. It's drawing about 400 microamps. It doesn't take amperes to get these things to glow. I imagine one could charge a supercap with a piezo element and have sustained light output with very little ongoing mechanical work needed.

  • But, that was my idea! (Score:3, Insightful)

    by HTH NE1 ( 675604 ) on Wednesday February 11, 2004 @02:24PM (#8251740)
    The piezoelectric transducer is sealed with resins, but is planned to undergo future improvements of waterproof sealing. Shaken in a container having a small amount of water, the Light Emitting Stick looks beautifully luminous between light rays reflected from the water, Nissin Electric said.

    I had an idea for luminous items in beverages before, but then I envisioned glowing beads that were neutrally buoyant so that any carbonation in the beverage would cause them to continously move around. I was going to call them "fireflies" and market them to trendy bars.

    Of course they'd either have to be safe for consumption or have the beverage container's opening be filtered with a mesh so they couldn't be swallowed.

    Think glowing skittlebrau.
    • How would you get them to not float or sink? You said 'neutrally buoyant', but isn't buoyancy dependent upon relative densities? The density of most beverages is changing so rapidly that it'd be nearly impossible, at least from my extremely limited physics knowledge.

    • Of course they'd either have to be safe for consumption or have the beverage container's opening be filtered with a mesh so they couldn't be swallowed.

      Look up the Japanese soft drink Lamune. It used a particularly unique design in which the drink was sealed by a marble stuck in the neck of the bottle. To open you pushed the marble down into the bottle. If you wanted to save a little for later you could flip the bottle upside down and suck on it, the marble would fall down and reseal the bottle.

    • Perhaps you could have a weight that would sink to the bottom, and have the beads tied to the weight by threads or wires?

  • K2 skis and airplane wings had these years ago (Score:5, Interesting)

    by goombah99 ( 560566 ) on Wednesday February 11, 2004 @02:27PM (#8251778)
    The K2 - "fours" have embedded piezos hooked to leds. the piezo's in turn are hooked to the fiberglass top sheet. when the ski vibrates excesivley the energy is damped by draining the piezo through a load, in this case an LED. The LED is used in stead of a resistor for two reasons 1) it sells skis cause its cool to watch and you know its "working". 2) the diode has a threshold for activation that turns on the damping only when the vibration is excessive. so your ski is lively up to a point.

    they got the idea from the airforce who uses this idea to damp wing vibration.

    in both cases active vibration is lighter weight than passive damping materials. (unfortunately the K2s are still heavy as sin, so really it was a gimmick aimed at nerds. still it worked--I bought the skis!)

  • Solar powered LED in a calculator (Score:5, Interesting)

    by G4from128k ( 686170 ) on Wednesday February 11, 2004 @04:10PM (#8252978)
    I once disassembled a early model of solar-powered credit card-sized calculator (one with no battery at all). While holding the circuit board near a light, I noticed a little glow ont he backside of the board. The designer had used an LED as a cheap voltage regulator. The LED lit up to dump excess energy coming from the solar cells.

  • Toys (Score:3, Insightful)

    by javaxman ( 705658 ) on Wednesday February 11, 2004 @04:54PM (#8253509) Journal
    Neat.

    But really, aren't these most likely to show up as toys ( both for children and rave-going tripsters ) ? At least on a consumer level, I'm having a hard time thinking of other good applications.

    Of course, the article was a little thin, and I'm left asking questions.

    How much light do these generate? I take it all the light-up kid's shoes we see have batteries in them, right? These won't compare to -or work for- that kind of thing... how many applications require that the light source _always_ works and doesn't need to be very bright ? Basically, I'm wondering if these won't be adopted too well because battery-based solutions will "outshine" them. And with LEDs, batteries last quite a long time. I know my son outgrows his light-up shoes before they stop lighting up...

  • Mix those P-LEDS plus a remake of MJ's 'Billie Jean' vid, and you'd have a music video that would appeal to the slashdot reading, pop-music loving "Gen X & Y"ers. Better yet, replace some of the LEDs with little speakers that say "Wooh!" Cool!

    Or not ;)

  • 10 Amps ?? (Score:2, Insightful)

    by rir ( 632769 )
    From the article:

    The Light Emitting Stick generates a current of up to about 10A


    10 Amps ?? Is it just me or does this seem a little high to anyone?
  • I had an idea a while ago to get large piezoelectric strips and put them in the roadways of the USA. They would power LEDs in the little road-top reflector thingies for enhanced roadway visibility. It'd be costly, but man it'd be cool!
  • People get all excited over this kind of thing, but it's nothing new. Long before there were piezo anythings, there were magnets and coils. Use a lever to disrupt the magnetic field through a coil, and the magnetic field colapses, generating power. I've even got one of these little thing embedded in epoxy, that was used as a gas igniter. You can replace the LED in the article with a capacitor and Neon bulb, and your've got the same thing -- only using technology that's been around for ages. Nothing rea

    • Re:Big deal (Score:3, Interesting)

      by drinkypoo ( 153816 )
      The difference is that piezoelectric materials, if made sufficiently convenient, can be employed in ways that are complementary to, and just as useful as, the generation of electricity by electromagnetic means, whereas your assorted magnet-driven gizmos have all required something outside themselves to actuate them. These materials are both actuator and generator.

      There are lots of things in this world that are designed to be in motion. Some of them naturally lend themselves to being made with piezoelectri

  • Those blinkin' boots-boots-boots-boots... (Score:3, Interesting)

    by dpbsmith ( 263124 ) on Thursday February 12, 2004 @09:38PM (#8265730) Homepage
    Don't-don't-don't-don't-look at what's in front of you.
    (Boots-boots-boots-boots-movin' up an' down again);
    Men-men-men-men-men go mad with watchin' 'em,
    An' there's no discharge in the war !

    'Tain`t-so-bad-by-day because o' company,
    But night-brings-long-strings-o' forty thousand million
    Boots-boots-boots-boots-movin' up an' down again
    There's no discharge in the war !

    --Rudyard Kipling, "Boots"

    Now if those boots had had little blinking lights in them...

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