DIY suspension generator / regenerator

[Daox]

We all know the up and down motion of our suspension is just wasted energy (or at least we do now that I just said it) . Anyway, Darin posted a while back about Tufts University electromagnetic shock absorber. It sounds like this shock absorber has a reasonable shot at completely eliminating an alternator unless you drive on roads of glass (haha, yeah right). So, how can we use their fancy design and make a cheapo DIY version? Lets get some ideas out there. This sounds like a good area to look at for 'free' energy.

My idea is to use a device similar to one of those shaker flash lights. You would mount a magnetic post somewhere on your A-arm and that would go up and down with the suspension travel. The coil could be mounted on an arm that is attached to the frame. The up and down motion would generate some electricity and it could be fed to charge the battery. I'm not sure on the specifics of how the shaking motion actually produces electricity, so you'll have to excuse my ignorance there. However, those shaker lights are cheaper than dirt, so I'd think we can make something up and keep it on the cheap.

What can you guys think up?

[Daox]

Here is some info on how the shaker flashlights work. As you can see, its a really simple device.

HowStuffWorks Autopsy - Inside a Shaker Flashlight


For those who know a bit more about electronics. How could we beef up this design to crank out more wattage? Is it just more coil windings and/or a stronger magnet? Or, are we looking at multiple coils and/or magnets?

[Tango Charlie]

Think of it as a linear alternator. In a typical alternator, the coil spins around, whipping its electromagnetic field through the stator windings. The shaking motion you refer to would be the same way of getting windings to pass through an electromagnetic flux field.

[Tony Raine]

i live on a dirt road, and we still have concrete highways with expansion joints. i see potential........


take apart a shock, and mount the magnet on the piston where the oil seals would be. put the coil around it.

i wonder how much power one of those flashlights "bridge rectifier" could take? i have one.


its too bad i don't know much about how electronics work. i have access to a few cordless sawzall's, and some brush motors for commercial vacuums. all just sitting with broken parts, because it was cheaper to replace than repair.

[Clev]

Would the shaker be the best way to recover the energy? I pictured something similar to a shock absorber with an external reservoir. The motion of the shock moving up and down forces the fluid back and forth into the reservoir, while spinning a little generator in-between.

[Daox]

The shaker probably isn't the best way, however it is a very doable way. I dunno about you, but I don't have the means to put together an external reservoir setup with a turbine generator.

[Clev]

Hmm... How about a bicycle air pump? They even have the ones with the check valve that pump air in both directions. Most are good to about 100 psi, and the foot-pedal operated ones seem to move a decent amount of air, so gang them together and connect them up to an air tool (grinder? screwdriver?) to drive a small generator. Kinda Rube Goldberg, but it might work.

[hansj3]

sorry to burst your bubble but mit beat you to the punch...
MIT shock absorber increases fuel economy

Levant Power Corp is the new company
Levant Power Corp.

In their testing so far, the students found that in a 6-shock heavy truck, each shock absorber could generate up to an average of 1 kW on a standard road — enough power to completely displace the large alternator load in heavy trucks and military vehicles, and in some cases even run accessory devices such as hybrid trailer refrigeration units. the group, which also includes senior Zachary Jackowski and alumni Paul Abel '08, Ryan Bavetta '07 and Vladimir Tarasov '08, plans to have a final, fine-tuned version of the device ready this summer. Then they will start talking to potential big customers. For example, they have calculated that a company such as Wal-Mart could save $13 million a year in fuel costs by converting its fleet of trucks.(taken from the first link)

it sounds really promising,however idling will be an issue

[Daox]

No bubble to burst. I know its been done before. I'm just wondering how WE can retrofit our vehicles to use it.

Extended periods of idling may be problematic without deep cycle batteries, however starter batteries would probably be fine for the majority of drivers.

[theunchosen]

The way electricity is made is fundamentally by pushing electrons out of orbit continously. The magnetic field sitting still displaces them but it just creates a minor voltage difference. If you move it you can make a flow.

You have to move the magnet in the direction with the right hand rule. Curl your fingers around the palm around the coil with your fingers pointing into the middle with the direction of the magnet. The current will flow in the direction of your thumb.

That said. . .the super easy effective way would be to put tons of copper coil windings around the actual spring and just mount a large magnet on either end(top or bottom, make sure you don't make it long enough to strike the other side under heavy load).

The up and down motion that the springs absorb would induce the current.

Its kind of simple. . .copper wire around springs(lots) and a really powerful magnet. Neodynium(sp I'm sure). Test it on one of your springs with magnet and then put a DMM and push down on that tire(jump on the chassis there if it will take it) and watch the output reading. . .

For a normal car I'd expect a max of 60 watts per tire. . .Although if your zorber is totally shot like a 86 stock buick town tank you could get a whole KW!