anti-roll-bar rallycars

[Laurent]

in an F1 car, its quiet simple to know whow Anti-roll-bars are working....

But on a rally car, I'm wondering how it's working (I always think that they has independent springs on each suspension....)

Thanks

[Guest]

They work very similar to those of the Impreza STI and Evo 8. So if you are able to make it to a Subaru or Mitsubishi service spot and can have a view under of one a.m. cars you will see where Anti Roll Bars are placed.

[DaveKillens]

x

[red300zx99x]

Hit a bump with the RF and the LR loads up. Theres an article floating around the internet about the 4 modes of suspension. Good read. This system has an effect on the 'warp' resistance of a wheel. But anywho the guy who wrote the article has a few different alternative to control 'warp' resistance. Too me any means to decouple a system(pitch, roll, heave, and warp) and control each system independantly would be ideal for control of these systems.

[Guest]

http://www.kinetic.au.com/techno.html

The systems mentioned if anyone would like a better description

Still searching for the article on the modes of suspension

[DaveKillens]

x

[mep]

Can we discuss a bit more how they do it in rally cars?
I am really curious about but I must admit that I know quite a lot about formula cars but very little about rally cars. I think we should look a bit beyond the horizon of F1 on this forum.

RacingManiac:
A hydraulically based system like the Kinetics System used in some rally car(and possibly in F1)will be able to decouple that.

Can you enlighten us how it works/looks like?

[Jersey Tom]

The Kinetic suspension is nuts. And banned in a variety of systems.

With regard to ARBs though.. an ARB is an ARB. Same concept on a sedan as an open wheeler.

[RacingManiac]

AFAIK Mitsubishi used it in their Dakar car up to 2006 when after the system was banned....it is completely passive and done through inter connected hydraulic at different corners, presumably with a bunch of check valves and manifold to control flow for roll and damping...

I think it was tried on some LMP car too back in mid 2004 or 2005(Racing for Holland Dome?), and a variant or something in the same vein may be used(or actually in use) in some F1 cars. I was merely told of the latter by someone in the know....

I believe Toyota actually used a version of the system on their 4Runner/Lexus GX...Monroe/Tenneco owns the patent(or indeed Kinetics as a company) now.

[mep]

The point that something is done with hydraulics attracts my attention.
Why is it banned? Usually banned technology is quite good.

[RacingManiac]

unfair advantage...blah blah...who knows....

Its still alive and well in Formula SAE though...lol

[Tim.Wright]

Even though I lived only a few hours from the Kinetic HQ I never got a chance to really check the system out. I think the company was recently sold too. From my limited understanding (based largely on assumed knowledge) it attempts to give you very soft single wheel lift (or warp mode) while retaining stiff roll and pitch modes. This is kind of a holy grail in suspension design.

From what I understand, the suspension on each corner is hydraulically connected to the other side (left/right) and the other end (front/rear). The routing is such that when one wheel goes into bump, it forces fluid into the rebound chamber of the other side. In roll this means the left/right connections are trying to force fluid against each other and the result is the fluid builds up pressure against a gas accululator which acts as a spring. This spring gives you extra roll resistance.

Nothing special so far, but when you consider bump on a single wheel, it pushes fluid into the rebound side of the opposing wheels forcing them also into bump and you get a very soft rate in single wheel bump.

University of Western Australia have made good use of it for a number of years in FSAE and they would know more about the system. There was also a good write up about it in ATZ last year.

Tim

[marcush.]

that was lammers system ...is this kinetic equivalent or the same?

http://www.creuat.com/
http://www.creuat.com/docs/Technical/CR ... t_Puma.pdf

[RacingManiac]

The Kinetics system acts on the shock level and AFAIK still uses regular ride spring(in UWA's FSAE car, torsion bars). The Lammer system which looks to be doing the essentially the same thing but seems to replace spring in ride altogether.

I think there are more than one way to skin this cat, and I am sure patent wise there are probably a lot of grey area....

[jon-mullen]

A clunk could be any component on the suspension. You should put it up on jackstands and wiggle the wheel around until you can re-create the clunking noise...and then find a Yaris forum.