How to Charge Any USB Device by Riding Your Bike

Step 1 Our original intention...

Our original project was to develop a product that used the Faraday Principle to allow runners to charge their iPods while they run. This concept would generate electricity the same way those Faraday flashlights do.
However, we had a problem. To quote my team mate Nick Ciarelli,

"At first we considered using a design similar to one of those shake-up flashlights and converting it so that a runner could strap it on for a run and have energy to charge their iPod or whatever device they use. The shake-up flashlight gets its energy from the interaction of the moving magnetic field of the magnet in the flashlight and the coil of wire wrapped around the tube the magnet slides through. The moving magnetic field causes electrons in the coil to move along the wire, creating an electric current. This current is then stored in a battery, which is then available to use for the flashlight bulb/LED. However, when we calculated how much energy we would be able to get from a run, we determined that it would take a 50-mile run to get enough energy to charge one AA battery. This was unreasonable so we changed our project to the bike system."

We then decided to use a bike-mounted system instead.

Comments

[mitpatterson]

The other thing with the shake up light idea, is that they tend to have a strong magnetic field, that may wipe the contents, or at least mess them up, on any Ipod or MP3 Player that has a harddrive. the flash based ones like the nanos, should be safer.

[orangesrhyme]

It takes a LOT of gauss to even slightly corrupt a couple of sectors on a hard drive.

[wupme]

I dont think that magnetic field would be strong enough. You need a really strong magnetic field to damage data on an hdd, much more then people would think.

[name101]

I put my Ipod classic on a "Magnet bender"(Used to bend sheet metal with the help of a magnetic feild.) While playing music... no hiccup at all.

[mitpatterson]

well, probably doesn't hurt it, but just saying that its probably not a good idea for it to be around it for LONG periods of time. I had a cell phone get screwed up once from one of those

[name101]

"not a good idea for it to be around it for LONG periods of time." I happen to agree with that :D I was just experementing with my iPod. If it broke i would take it back to apple and claim a new one on warranty claiming harddrive failure :P.

[dungeon runner]

The magnet definitely wouldn't be strong enough to wipe the hard drive, although you might worry about the screen.

[revhead]

i have one of those shake it torch things and i pulled it apart and found that the magnet inside it was VERY powerful! i strugled to full it off the frige door, the only way i was able to get it off was to slide it off the edge of the frige. i dont know much about hard drives and such but it might be possible to corrupt the files with this sort of magnet.

[wupme]

Probably a neodymium magnet. But i still think not strong enough. You gotta remember that a magnetic field of such magnets loses drastical amounts of force when you increase the distance. Also harddrives are somewhat protected from magnet fields. I tryed with neodym magnets how much it actually takes. Now i dont remember what size the magnet was, and how strong he was, but a lot bigger and stronger then the once used in such lights. And the interesting thin, before i had data los... the motor failed completely from the magnetic field. Well ok, thats also a destroyed hdd then, but still interesting ;)

[drakesword]

Hard drives have a powerful neodymium magnet within the drive as part of the control mechanism for the read head. They sit RIGHT next to the platters. Wouldn't THAT corrupt data too? It doesn't, your good.

[uberdum05]

Yeah, but might there be a slight possibility of the other magnet changing the position of the HDD head and making data go corrupt in a bad way ?

[drakesword]

slight but the voice coil (the device that controls the arm) sits practically on top of the magnet. Any magnetic interference will have to change the magnetic field at the millimeter scale. I may set up a test with an old HDD if I can get my hands on one.