DIY suspension generator / regenerator

[dutchboy]

Originally Posted by Christ

Post #40. Air shocks have a single inlet/outlet fitting on them. You'd have to tee off it and put check valves in the lines, so that the compressed fluid (air) could only flow in one direction through the circuit.

So the shocks have one fitting, that has inlet and outlet passages?

You talked about using a light oil instead of air for even more efficiency...I assume you would use an air hose fitting to get the oil inside?

[CobraBall]

U can read the Tufts U. patent for the Electromagnetic Linear Generator and Shock Absorber at Electromagnetic linear generator and ... - Google Patent Search
Patent number: 6952060
Filing date: May 7, 2001
Issue date: Oct 4, 2005
Application number: 9/850,412

[Christ]

Originally Posted by dutchboy

So the shocks have one fitting, that has inlet and outlet passages?

You talked about using a light oil instead of air for even more efficiency...I assume you would use an air hose fitting to get the oil inside?

Something like that, yes.

The shock has one fitting on it, which (normally) would only have 1 hose hooked to it.

If you tee off that fitting, that allows two hoses. Put a check valve in each hose, so that the air can only flow through it one way. Put a bladder somewhere for the pressure to escape from the shock. Plug the two lines into the bladder, with the turbine in one of them (or both, if the energy is there).

The shock body itself actually doesn't have an inlet/outlet, just the single open port on the side... it's not even valved, that I know of.

As far as putting oil in, you'd just want to put a line/fitting on that opening on the shock, just like if you were going to pump it up with air. You'll want to draw a few inches of vacuum on the diaphragm inside the shock, then transfer the line into whatever oil you want, and pull the ends of the shock to full extension. This will fill the shock with oil, and you'll have to drain some off to set the ride height after your system is together and operating. (You'll need a bleeder valve somewhere in the system to remove air, so just use the bleeder valve to pull some oil back out of your (functional) system, which in turn will lower the ride height of that axle.

[shovel]

I was thinking a few days ago about these things



It's a kinetic subwoofer... so to speak. You bolt it to your couch, hook it up to the sub channel of your home theater, and it jiggles your cheeks when a movie's playing rumble.

But in reverse, wouldn't it generate juice?

Could you bolt it to an unsprung part of your suspension, wire it through a rectifier to a DC-DC supply (as in this thread) and charge your battery with suspension movement? Sure, it would be marginally more unsprung weight and would have some effect on damping (energy isn't ever 100% free and the relative stiffness would change with load..) but it'd sure be whimsical anyway

[Piwoslaw]

shovel:
DIY suspension generator/regenerator

[shovel]

Sweet! I suppose my buttkicker idea should have gone in that thread, if I had known about it.

A while back, woot.com had buttkickers for some silly low price like $20 for 100w units, I have to figure that a unit made to operate at 100w as a motor should similarly be able to produce around that much as a generator right? (assuming full kinetic potential is being taken... which it should at least half the time on anything but the smoothest of roads)... and talk about a simple system eh? one moving part, completely enclosed.

Now to see what can be had in buttkicker-like devices on the cheap...

[Daox]

Moving posts is no problem.

[punkinhaidmartin]

I have to wonder how well this technique would work on a large vehicle like a refuse truck, freight truck or bus.
Over the road heavy vehicles have lots of space between the axels and the body where these devices could be installed. There is a huge amount of un-suspended mass which means that the shock absorbers have to dissapate a huge amount of energy. The weight to HP ratio of these vehicles is a lot more heavy on the weight side. A caterpillar C7 engine is only about 210hp but has torque out the wazzoo. They generally carry an alternator that will produce 165 amps at the low end and up to 320 on the high end.
I would think that these linear generator type shock absorbers would be more easily retrofitted to large applications either as an additional shock absortion system or as a replacement to the current systems. The shocks are pinched between the ground and up to 90,000 lbs of suspended mass so the energy to be dissapated is a lot more and the stroke on the current shocks is as much as 30".

What do all you more knowlegeable folks think these facors will mean to this sort of recouperation scheme?
One more neat thing about these devices, you get to recouperate some of the energy that it took to get you up a hill when you go down a bumpy hill. They harvest energy invested in the system by gravity.

[ShadeTreeMech]

Originally Posted by Piwoslaw

During idling, the driver (or driver+passenger ) could jump up and down inside the car, working the suspension...

Is that to say some marital procreation practice would keep the lights burning bright?

[ShadeTreeMech]

i'm a fan of the pneumatic approach. Fit the car with air cylinders in the place of shock absorbers. With restricted outlets, it should provide more than sufficient shock absorption. (aren't some of the best shocks nitrogen charged? I think there is a lot of nitrogen in the atmoshpere...) Run lines from the outlet of the cylinder to a tank to store the compressed air. When you have an overabundance of air, bleed some off through a pneumatic motor attached to a secondary permanent magnet alternator, and you've got electricity.

The advantages of the pnuematic approach is the cheapness and ready availability of parts, as well as lightness and easy ability to store energy in the form of compressed air. A hydraulic system would be a bit heavier and expensive. And a leak in the system would be a big deal with hydraulic oil, not a issue with compressed air.