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Energy From Vibrations
JN writes "Now here's a nifty invention. What started off as a Small Business Innovation Research grant from the Navy to a MIT professor has turned out to become a great mechanism that harnesses running machines' minute vibrations into energy. The possibilities are limitless. Aside from the obvious, imagine the ultimate cellphone - one that charges the battery every time it rings/vibrates, hence promising extended talktimes, and giving operators all the more reasons to get their customers to use their devices. How cool is that? Do I see 3G applications with a vibrate() call mandatory every couple minutes?
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On a Harley block these could power my Microwave!
Reminds me of this article. But seriously, wouldn't the daily movement of the cell phone user also be useful? Granted, it's not as vigorous as the vibrate feature, but it has to account for something.
"Crud, I dropped my cell phone. But now I have ten more minutes of talk time! Gotta love solid state!"
A programmer is a machine for converting coffee into code.
I know plenty of women that get energy from vibrating objects.
Yes! A phone that charges itself when it rings or vibrates.
And next, we can build a machine that, when slowing down from drag, uses that potential energy to cause another part of itself to move faster. Then, it would never stop. We could task it to make electricity to power... everything!
From cars that have more electricity at the end of the trip than when they started, to bicycles that coast faster when going uphill, the possibilities are... perpetual!
fifth sigma, inc.
This is a way to power small, low-power devices parasitically from the vibrations of a much larger engine. Actually very interesting.
> one that charges the battery every time it rings/vibrates
I sure hope you are just making a joke. If you're not being deliberately stupid, I impressed by your natural talent.
Anything that obtains energy from vibrations or sound is going to dampen those vibrations or muffle the sound [same thing really]. If phones can save energy like this, maybe you can levitate by pulling your own hair up. In fact, I recommend you try this.
http://rareformnewmedia.com/
The patent is certainly intended to cover large scale industrial equipment, not mobile phones. In that case, not only would you get excess electricity, but the very act of harnessing that power would also serve to quiet them -- a double bonus.
Hemos is like a lot of sci-fi fans: he thinks technology is cool, but he hasn't bothered to understand the science it's based on.
This is one slashdot story I'll need to read at -1, just for the vibrator trolls
The vibration of a cell phone is not wasted. It is intentional. To pick up energy from the vibration would be to damp it, then you'd have to vibrate more to get the same alerting effect.
Even if you could get power from the vibration, it would mean that the vibration (which is intentionally selected) is unwanted, or that you would have to crank up the power going into the vibration to compensate.
This supposed energy collector is meant to pick up wasted, unwanted vibrations from engines, ventilation ducts, etc. Not from intentional vibrations.
Infuriate left and right
I dunno about this -- my girlfriend seems to have no energy whatsoever left after I apply vibrations to her for 10-15 minutes straight...
I had an idea kind of like this a while back, when I had to replace the little watch battery in the key fob for my car (the little remote-control that unlocks my doors). So instead of having to replace this battery, I thought it would be a good idea to make it a small rechargable battery. It would utilize the kinetic vibrations of the car, which would be transfered into electricity. Or to be more precise, inside the keyfob would be a tiny magnet on the end of a tiny spring. The vibrations would cause the spring to wave the magnet around, and the moving electromagnetic field would be transferred into electricity.
This would be especially efficient for the keyfobs that are part of the key structure themselves, so that they are directly connected to the steering column (as opposed to the ones that are simple part of the keychain and just dangle under the steering column)
And it's not like I'm claiming originality on this -- I got the idea from a tiny cell phone a friend brought back from Japan. It had no connectors on it to recharge the battery, but the recharger base would vibrate when the phone was set on it, and passed the electicity via electromagnetic fields.
Punctanym: alternate spelling of words using punctuation or numerals in place of some or all of its letters; see 'leet'
Please. Everyone should make basic errors in logical reasoning in their submissions, that way, we'll never talk about anything else. Slashdot will be ruined. My evil plans will come to fruition! Ah ha ha ha ha HA HA HA!
There are no trails. There are no trees out here.
The article is (I assume) about energy recovery/scavenging
Classic slashdot. You know, you could actually read the article and find out. You do go to berkeley.
the article poster just invented perpetual motion, arguing that the vibrator from the ringer could power the cellphone.
Well, he didn't imply "power," he stated "recover." As others have mentioned, any vibration recovered isn't giving you that tingly feeling that says your phone is going off. So nothing doing there, but Hemos isn't quite as daft as you think. (Insert ./ editor joke here)
What this article is really about (I feel like I'm making Cliff's Notes here for the science-deprived) is not recovering a significant proportion of power from a low-power device like a cell phone. It's about powering a milliwatt-draining device like a sensor off of, say, a megawatt-producing device like a nuclear reactor. This is actually kind of cool, since as the article states (for the literate among you), there are places with no light, no wiring, and a lot of vibrations where you might need power. So this has the chance to do some cool things - just don't expect it to actually extend the life of your cell phone or be a perpetual-motion machine.
On the interesting side, this would make a cool way to create non-powered earthquake sensors. When it gets a quake, it transmits its position and maybe have the power out proportional to power in. You could distribute hundreds of them and have a real-time quake sensor that might be better than triangulating.
Also, could be useful to track vehicles if you slap it on the chassis. Again, deploy once, no worries about going dead.
Imagine. Your systems are running fine, and suddenly half of your sensors stop working. Two days later you find out it's because the HVAC man came around and upgraded all the old compressors' parts to run with no vibration ('cuz it increases the life of those machines, you see), and now all your little micropowered machines have stopped working.
It would seem to me depending on a machine to be inefficient (and thus stealing some of its wasted energy) has this equivalent in the software world: depending on a bug or deficiency in the OS to make your application work. Someone's gonna finally think to fix that bug or deficiency.
fifth sigma, inc.
Damn thermodynamics... always holding us back.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
perpetual motion is possible! ... Proof? Earth's revolution around the sun, the moon's revolution around the earth etc.
Suggesting that the movement of celestial bodies is "perpetual motion" is ludicrous.
"Perpetual motion" (in the context used here) means that you can extract more energy from a device than you put in - which is clearly impossible.
Even taken literally (ie. that something will continue to move forever), it's still not possible - your examples just show that you don't have a very firm grasp of physics, or knowledge of astronomy or geology.
The earth will not continue revolving around the sun indefinitely. It's gradually slowing down, and will probably be consumed by the sun before it comes to a complete halt.
Imagine an energy scavenger like this inside a standard PC keyboard. You could power Intels hungriest processors using Windows and Ctrl-Alt-Del...
"I don't know why we didn't see it before", stated a young lab assistant at the M.I.T center for alternative energy. "I wonder if Thomas Edison truely realized the potential in his invention."
-- Thou hast strayed far from the path of the Avatar.
Of course, one can't get any more energy. Duh.
/s = 21.3 W.
But exactly how much energy could one get out of a vibration? Are we talking powering an LED by the San Andreas fault? Or are we talking powering San Francisco from the vibrations on an air conditioning shaft?
Let's see:
We'll consider the vibrations to be simple harmonic motion (because it is relatively accurate, and anything else is near impossible to calculate without a beowolf cluster).
Let's look at the vibration when your car goes over a speed bump. This should have a relatively large energy associated with it, since the energy in a object due to vibration is:
E = 0.5 K A^2
Where k is the spring constant (in metric, it would be N / m ).
K can be determined by calculating how far your car is lowered when you get in (your weight, in newtons, divided by how far your car is lowered, in meters).
Let's assume that you weigh 150 lbs. This is about 70 kilos, or 670 Newtons. Let's also assume that your car is lowered by about an inch when you get in (0.0254 m).
This makes the spring constant for your car's suspension:
670 N / 0.0254 m = 26,378 N / m
This is to say that if one were to depress your car's suspension by one meter, you would be exerting a force of 26,378 Newtons.
Let's also assume that, when going over the speed bump, your car bounces 10 inches. Thus, the amplitude of your car's motion is 5 inches, or 0.127 meters. Putting this information, and the spring constant into the first equation for energy:
E = 0.5 ( 26,378 N ) ( 0.0127 M ) ^ 2
E = 213 Joules.
Great. How does this relate to power needed for powering some electronic device?
Power = Energy / Time.
Let's assume that this vibrations to energy device in the article can absorb your car's vibrational energy in 10 seconds. Thus, the power going into the device is:
213 J / 10 s = 21.3 J
That's right. 21 watts. Barely enough to power a small lightbulb. And that is coming from a whole car!
Thus, I think that we can safely say that we're not going to be replacing our power plants any time soon. But for, say, a low-powered electronic sensor, which wirelessly broadcasts it's data in bursts every ten seconds, it would be fine.
More importantly, let's hope for commercial windmill farms that don't kill birds.
better yet, a windmill farm that converts the birds it kills into energy.
If you mod me down the terrorists will have won
Always, as long as there is a remote possibility of it applying to the subject. Sometimes even that isn't a necessity.