How to Make Electricity When You Run!

About: I'm a teen aged geek living in Nova Scotia, Canada. I feel safe giving this information because I live near another Shane Dulong. Normally I'm not very trusting of the internet especially due to the fact I f...

Don't you wish the kinetic energy used when you run could be attached to other things? Well know it can! This is an idea I got of of Daily Planet. Theirs was way better, but I wanted to make my own!

Step 1: Materials

Materials needed:
Piece of plastic or tough material in rectangular prism form (see pic)

And last but not least:

A crank flashlight! (must be a squeeze kind)

Step 2: Expand Crank!

It's quite simple:
Glue the plastic thing on the crank.

Step 3: Put on Harness

Glue on the harness that you will strap on your leg.

Step 4: Use!

Put it on right under your knee. Now when you run, It will press the switch and generate electricity! If you want, you can find some instructions to charge cell phones and iPods with these crank lights! Here's a link:

Plus it is guaranteed you can find more than this!

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    15 Discussions

    I saw a report on Daily Planet about an energy-harvesting knee brace, once. Their plan was to implement it with Soldiers, since they do a lot of walking, and these days, need like 8kg in batteries for all the advanced equipment they carry. Here's an article on the same study:

    I've thought of doing something similar. All you'd have to do is connect an angle joint to a standard knee brace, and then rig up one of those bike tire generators to that, and set that to charge a battery, or your cell phone or something.

    Would actually be really handy for charging batteries for Geocaching. Drain the batteries with your GPS while you charge a new set by walking.

    4 replies

    Ach!!! You beat me to the punch!! That's exactly what I thought when I saw this instructable. The knee brace is definitely the way to go; comfort and design. Probably need two to prevent over-using one knee. How much physical resistance does the crank currently place on the knee? How would it affect sprinting / running? Perhaps a pull pin to disengage the generator in situations where speed is when people are shooting at you? With the addition of a second knee generator, the resistance could be decreased a bit for both, adding to your overall travel distance before fatigue sets in.

    If you want to make it work more like the one made by the pro engineers, it would take a lot of complex gearing and electronics. On the other hand, the principle of their design had the option of only collecting energy when you step forward. This could easily be achieved by much simpler means. Two ways I can think of off the top of my head are to set up some kind of push button to disconnect the generator when you apply force backward (when you are in the "power" phase of your step), and reconnect it when you step forward to break your fall. Wish I could draw to illustrate the idea. The other idea would be to add some kind of gearing where the teeth on the gears only drive the generator shaft when it moves one way. And if someone really wanted to invest a lot of time, it would be possible to use a combination of all of the above and control everything with a microcontroller with lower power requirements and just power it off the walking device.


    9 years ago on Introduction

    This is good idea,but it would take nearly to walkto recharge a AA battery.

    Phil B

    9 years ago on Introduction

    I think I would find the continual thump of the crank lever against the underside of my knee irritating enough to cause a sore spot. I would probably prefer one of those flashlights with a sliding magnet and rig it to charge a battery I could use in something else.

    2 replies
    HarveyH44Phil B

    Reply 9 years ago on Introduction

    Think I would have mounted it to a shoe, maybe strap it on top the foot, and extend the crank/lever as needed to contact the ground. Surprised Nike hasn't done this yet...