Cross linked ARBs ?

[autogyro46]

A few (well, 5+) years ago there was a flurry of articles, prees releases, etc. about an integrated hydropneumatic springing system which provided global control of the behavior of all four wheels (you might call it a Global Positioning System) in four modes: bounce, roll, pitch and warp, by a Catalan concern, Creuat S. L.
The sysem essentially seems to work by providing separate stiffnesses for different pairings of wheels, as do ARBs. What makes it intersting is that two of the pairings are diagonal, providing stiffness to both roll and pitch.
There is an SAE paper on it which I've provided in an attachment. There are also several patents.
Digging a little deeper, there are others in the game, including Toyota, but the idea goes back at least as far as 1962 in a Volvo patent (US #3,147,,990)
Of course, coupled hydroelastic springs aren't new either, witness the Citroen DS19, and the BMC Hydrolastic setup of the 60's.
So the obvious question is, what happened to this ground-breaking, game-changing, paradigm-shifting, world-beating (AHEM!)idea ?
Was/is there, as a friend used to say, "a flaw in the ointment"?

 

[GregLocock]

One of the user definable traits in active suspension is warp. I'll try and remember to ask the only perosn i know who played with it how useful it was.

I suspect you'll find that a mechanical warp linkage adds $100 to the car for $10 of benefit.

Moulton was rather keen on pitch linked suspensions, and I could have sworn that the 2CV had a pitch bar.

Cheers

Greg Locock


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[MikeHalloran]

The 1953 Packard did something similar with coupled torsion bars.



Mike Halloran
Pembroke Pines, FL, USA

 

[autogyro46]

Thanks to both you .
You were right, of course, Greg, about the 2CV. I'd forgotten that it had longitudinal springs on either side of the car, coupled to leading and trailing arms front and rear.
And evidentlly it worked rather well. And this, I gather, was in the late 30's, after Michelin took over.
Another coup by the great Andre Lefebvre. I hope sombody has done a good bio. He deserves it.