Breath powered USB charger

Step 1 Introduction and Step 1

This project requires a wide range of "maker" skills, such as PCB board manufacture, dismantling of electronics, cutting and drilling plastics, mixing epoxy, designing a gear train, kludging together a bunch of parts, bending paper clips, and risking the well being of your ever so expensive phone, camera, or PDA. All in all, good fun.

Since everyone will have a different collection of junk parts to build this from, I will just give you a detailed overview of how I went about it and you can apply these ramblings to your own project. Which will consist loosely of four steps.

1. Scrounge up some suitable parts for the generator
2. Build the charger circuit
3. Assemble the generator, thorax coupler, and mechanical return
4. Connect the charger circuit, and test

Step 1:

I had about four old CDROM drives hanging around and took apart a few of them to see what cool parts were inside. Turns out there are lots of cool motors, gears, and other parts inside that fully validate my insistence of keeping such crap laying around. Seeing the gear trains inside these units used for opening the tray gave me the idea for this project. The small low-torque, high-RPM motor is linked to the tray via a gear train that has a final ratio of about 20:1 Previously I had been using a parallel array of tiny pager motors to generate electricity from breathing (see below) but the linear travel from your chest expansion is not that great (around an inch) so in order to generate useful voltages you had to really huff and puff.

Anyway, tear into those CDROM drives, which you can find at pretty much any garage sale, thrift store, or landfill. The pic below shows the results. Lots of potential projects in there. For now, we are only interested in the plastic gears and the motors for opening the tray and/or moving the laser carriage.

Look over the various gears and drives and try to visualize a way to add additional gears to increase the gear ratio, or how to add another motor in series. You want to minimize the changes to the gear train. Alternatively you can just scavenge all the gears and build your gearbox up from scratch.

You are also going to need at least one motor with a small gear or pulley on it so that you can connect it to the gear train. The motors in the CDROM drive are typically simple permanent magnet DC motors designed to run on 5V, except for the spindle motor, which you don't want to use anyway.

At this point you also want to think about what you are going to use for a strap to go around your chest. An old belt, some webbing, an old shoelace, a name badge strap, or anything that will fit around you comfortably without any stretch to it. You want all the expansion to take place in your linear generator. Any stretch that occurs in your thorax coupler will be wasted energy.

Comments

[tjmortenson]

(removed by author or community request)

[DarkTrinity]

You can't be serious....

[Gjdj3]

I read that when I took mine apart too. My message for you is... Dude, don't worry! It only matters when the drive is in action and it's not the kind of radiation you're thinking of anyway.

[Coolbreaze]

Lol I'm guessing the removed post was about the Radiation Generated by the Cdrom/dvdroms Laser. For those that don't know Light Amplification by Stimulated Emission of Radiation that's what LASER stands for. There is No radiation involved what so ever in this device since there is no laser. And keep in mind SIMULATED Emission of Radiation.

[tjmortenson]

(removed by author or community request)

[Gjdj3]

Sorry for the repetativeness!

[Xellers]

LOL! That's all I have to say...

[Father Christmas]

only applicable when drive is in operation and immediately after.

[lovely2]

Huh, are you serious.

[george r. m.]

man,the radiation is there just with the device turned on,and it does not harnesses cells,but if you look at the laser ,it may blind you.i've been destroying cd players since i was five,and i'm still ok

[lampajoo]

I love the funny side comments. =)