Slashdot Mirror
Typing Recharges Laptops?
TwoSticks writes "Compaq patents a keyboard that captures your kinetic energy. Magnets and coils on each key charge a small battery to augment the big one in your laptop. Standard NYTimes deal: requires free registration. "
I'm a bit suspicious but it looks interesting. It might give
me an incentive to fix typos anyway ;)
A keyboard power generator provides a plurality of keys with one or more magnets mounted thereon. Additionally, a plurality of coils are mounted on both ends of the magnet such that, when the user is typing, the magnet traverses the coils. The movement of the magnet over the coils causes a current to be generated. In one embodiment, one magnet is mounted per key on the keyboard. In a second embodiment, a plurality of magnets are mounted per key to enhance the power generation capability of the keyboard. The currents generated collectively by the keys are provided to a charge pump which multiplies the voltage to achieve a level greater than the voltage level of the battery to be charged. The multiplied voltage is provided to a charging circuitry such as a trickle charger to recharge the battery. In this manner, the more information entered by the user, the more electricity is generated by the keyboard power generator. The energy provided by the keyboard of the present invention can be used to lengthen the operating period of the portable computer, or alternative, can be used to reduce the size of the primary battery so as to result in a lighter portable computer.
This keyboard sounds like it would wear out your hands pretty quickly. You have to expend enery to generate electricty, and I doubt you are going to get much energy from a keyboard unless you make they keys very hard to press (or have very long tavel on each key). On a standard laptop keyboard (with almost no travel) I doubt you are going to get more than a few seconds of battery life out of your keystrokes, even if you are typing a huge amount of text all the time.
Anybody remember those generator powered headlights on bikes? Remember how hard it was to pedal whenever you tried to use it?
Wasn't there an April fools joke similar to this this year?
I read the internet for the articles.
--
Extracting energy from keyboards may not be too far fetched. I have a keyboard from an old 1975 (Xerox?) terminal that uses HAL effect sensors solderd to the kefboard for each key that had a small magnet glued inside. The resulting feel was a very smooth and quiet keystroke. Quite pleasant for the fingers. I would imagine a coil may not have made enough finger friction to notice. It is a fine keyboard and had something like 140 keys and powerd by an Intel 8080 processor with gold connections on everything.
My guess is that the idea is being implemented with a goal NOT to be the sole source of charging power for the battery (otherwise why have a battery at all?), but rather to stretch the amount of time the battery can power the notebook on a single charge. This would be similar to the idea of regenerative braking in electric vehicles.
;-)
This does make the mind wander with all kinds of other possibilities. What about capturing the energy of ambient sound waves? Then the swearing and cursing prompted by the Blue Screen Of Death could actually be put to constructive use.
About a forth of the way down this page (sorry, no cid link)...
Christopher A. Bohn
cb
Oooh! What does this button do!?
you can view the patent here
U S05911529__
http://www.patents.ibm.com/cgi-bin/viewpat.cmd/
- MbM
- MbM
Sure. This is actually pretty easy.
Energy per keystroke is force * distance, or 0.01 J. Keystrokes per second times energy per keystroke gives energy per second (or power), which is 0.1 W.
So, it doesn't look like this is viable unless we have *really* low power notebooks
What I really need is something that will harness the energy of this incessant tapping. Give me some dummy keys or something that I can tap on and I think I could run the entire floor.
Apparently it burns alot of calories so why not put it to other uses too?
Edu. sig-line: Choose rhymes with lose. Chose rhymes with goes. Loose rhymes with goose.
Comparing? THEN use THAN.
Please, I beg of you, do not encourage the loud typers.
There is nothing more annoying when you're sitting in the school computer lab at 3 am trying to puzzle out a particularly gruelling problem than someone who loves to hear themselves type. They pound away at the keys as loud and fast as possible, convincing themselves that they are cool due to their rapid button pushing skills- nevermind that a trained monkey could do the job just as efficiently.
These people are second on my list of annoyances only to people who like to hear themselves talk while in line for a club.
Do *not* give them a legitimate reason for this loud-typing behavior.
--
Grouchy and loving it.
-- First post (by a female living in a state that begins with M and does not end in a vowel with a birthday that falls
Save all your work now.
Oh crap!!!
askjhadslaashkjaasdkhdasasdsdhasdkasdsdajdashasdhd asdashdashshsdahaskdsahksdadsdaskjdaskhsdahsdaksda ksadsdhdashkaskhdashkdsasdahsdakdashshkahjdaskjasd sdflakldfslhjsfadhjlfsdakfdsalkdfsfdslffkdsalksjfk sdfafsdajhdfj;fdsajsdfahjfasd;jsdfa;fsdahsfadhjsdf
Power has been restored. You may now resume work normally.
- - -
I'm not going to use a keyboard that requires
me to apply more than 5 newtons to a key.
Let's say the key course length is about 2mm.
That's 10^-2 J per keypress, neglecting the losses
in transformation from mechanical to electric
energy.
You need 10 keypresses to get 0.1W of power for
1 second.
Forget about having your notebook run on that
alone. Keyboard power is somewhere between
"little influence" and "neglectable".
Could be more practical for a PDA without a
hard drive, but then the trend for these things
is not to have a keyboard at all.