Cogito ergo spring

[Matt F]

I've been giving this supension qustion a lot of thought.  Well, perhaps not a lot of thought, but it comes to mind at odd and idle times.  So what I've come up with may or may not be helpful.

My first thought is that the "if you stand on the car, do the damper bodies move?" test might not be quite right.

If you could fix the frame solidly, and then stand on the front wheel, or seriously lift the same wheel, it would droop or bounce.  This would pull or push the steering linkage, which would work the rack, and then the pinion, and then move the steering wheel.

So the movement in the front wheel caused the steering wheel to move; but we wouldn't say that the steering wheel is unsprung mass.

I think that a better definition of unsprung mass might involve the bits and pieces that change in geometry as the wheels go up and down.  That's pretty simply, but I think it's pretty accurate.

Of course, it's better to have less weight in any of the suspension components.  But if the shock and dampener work in a strictly linear fashion, as actuated by rocker arms, I'm not sure that the weight of the components is very important.  As long as the springs do their job, and the dampers do theirs, and both are mated correctly, and they are also help within the body of the car, I'm not sure that inverting them would do much for either ride or steering sensitivity.

But, as I said, those are my random thought, and I encourage others.

--Matt

[Matt F]

Cogito ergo nihil, if that's the right declination. 

[Bruce Fielding]

[quote="Matt F"]
Cogito ergo nihil, if that's the right declination. 
[/quote]

I think, therefore I am nothing?

[ka mano]

Aurigo ergo sum.

[Matt F]

That isn't right at all.

I need to start over.  All I really remember is "agricola, agricolae... um... agricolarum... um..." 

Oh, never mind.

[Bruce Fielding]

Bellum Bellum Belli Bella Bello Bello
Bella Bella Bella Bellorum Belllis Bellis

'There having been wars'

Used to be able to do that in Greek, too - once upon a time when I was clever and did Latin and Greek at 'O' level...

Oh, and as for Agricola:

agricola agricola agricolae agricolae agricolam agricola
agricolae agricolae agricolarum agricolis agricolas agricolis

How many other car forums teach you ancient and dead langauges?

[Matt F]

Well, my Latin is obviously lacking.

Are my thoughts on suspension any better?  Or is it time to let this thread quietly fade away?

[jaimin]

Want a hand? "Racecar Vehicle Dynamics" by William and Doug Millikien avalible off the www.SAE.org website. The proper term isn't rocker arms, its bellcranks and push rods. since unsprung mass refers to anything not supported by the shocks and dampners, uprights, rims, brake discs and calipers, etc. shocks do apply. orientation COULD produce different effects, but more would be gained by weighing corners. on the subject of weighing, for you US guys, try Longacre scales, they are worth every dime.

[Matt F]

[quote="Bruce Fielding"]
[quote="Matt F"]
Cogito ergo nihil, if that's the right declination.   ;)
[/quote]

I think, therefore I am nothing?
[/quote]

Wait a minute...  That's not the right translation either.

Wouldn't it be "I think therefore nothingness?"

And I need some help to translate ka mano's Latin...

(Thank you to Jaimin for a real response.)

[ka mano]

hint: think 'chariot'

[Matt F]

I got it now.  Thank you!