How does adaptive or electronic suspension work

[spidey07]

You see the commercials, about suspension adjusting to driving or conditions. In particular I was talking to a guy with a 2006 BMW M5 (incredible drive). You hit the M button and immediately everything tightens up. I can see the transmission, with the M particularly, but how in the world would you do this with suspension components?

A side shock absorber oil reservoir beside each one that gets closed via a solenoid? I can't see a mechanically safe way to limit travel but maybe it does change dampening characteristics? I mean it can't change the springs on the fly?

I think F1 cars have something much more advanced, maybe the operation is similar?

 

[MikeMike]

the adaptive shocks are pretty much normal shocks, but they have something in them in order to thicken the oil by electronic charge...

http://delphi.com/manufacturer.../other/ride/magneride/

 

[alpineranger]

http://en.wikipedia.org/wiki/Magnetorheological_damper

 

[spidey07]

Thanks guys. That's pretty freaking amazing. So these claims are ONLY a change of dampening characteristics, by using this technology? Coupled with the right springs that could totally change everything.

If I'm reading MIKEMIKE's link correctly, this is truly variable dampening based on the strength of EM field applied? Is this the same or similar to formula cars?

Fascinating.

 

[overst33r]

Originally posted by: spidey07
Thanks guys. That's pretty freaking amazing. So these claims are ONLY a change of dampening characteristics, by using this technology? Coupled with the right springs that could totally change everything.

If I'm reading MIKEMIKE's link correctly, this is truly variable dampening based on the strength of EM field applied? Is this the same or similar to formula cars?

Fascinating.

Pretty sure active suspension is banned in F1.

 

[spidey07]

Originally posted by: mariok2006

Originally posted by: spidey07
Thanks guys. That's pretty freaking amazing. So these claims are ONLY a change of dampening characteristics, by using this technology? Coupled with the right springs that could totally change everything.

If I'm reading MIKEMIKE's link correctly, this is truly variable dampening based on the strength of EM field applied? Is this the same or similar to formula cars?

Fascinating.

Pretty sure active suspension is banned in F1.

Well that's my question - how does it work, seems to be answered.

Just like anti-lock brakes made it's way into our vehicles, what's the link between racing and what we can buy?

 

[sjwaste]

Originally posted by: spidey07
You see the commercials, about suspension adjusting to driving or conditions. In particular I was talking to a guy with a 2006 BMW M5 (incredible drive). You hit the M button and immediately everything tightens up. I can see the transmission, with the M particularly, but how in the world would you do this with suspension components?

A side shock absorber oil reservoir beside each one that gets closed via a solenoid? I can't see a mechanically safe way to limit travel but maybe it does change dampening characteristics? I mean it can't change the springs on the fly?

I think F1 cars have something much more advanced, maybe the operation is similar?

Hell, my 91 Supra has an electronically adjustable suspension. In this case, it's actually mechanical via a solenoid adjusting the shock valve body. Therefore "electronic" is only partially true, but hey, its old. There are actuators on top of the shocks, and the shocks themselves have an adjustable valve, the one that bleeds pressure between the two tubes in the assembly itself.

There's a button in the middle of my console to set the base as normal or "sport" which is stiffer, and there are a few sensors that modulate the firmness based on braking, acceleration, speed, and a couple of others (steering wheel position, i think). There's a little LED strip in the instrument cluster to show you where you're at.

Of course, being designed years ago, it's not adjusting at 500Hz, nor is each corner independent. And in reality, I believe the valve body of the shock only has three discrete positions. There's no adjustment on the bound/rebound independently, nor is there any adjustment for travel. It's based on pressure bleed within the shock, not EM or any variable viscosity fluid, but it's still pretty cool. Matching the correct spring, if you go aftermarket, is very important. There are one or two compatible aftermarket shocks on the market, as well, which helps if you want to lower.

Still, for a car designed over 20 years ago, it's very cool.