Where is the Anti Roll Bar located on a F1 car?

[autogyro]

I do not see any need for an ARB.
The connection between the left and right linkage through the T bar effectively controls roll and the center vertical pivot rod (which probably connects to a transverse torsion bar also a third spring)is mounted in a slot, which allows adjustment for the droop reaction on one side caused by the bump on the other.
You would adjust this effect and then re adjust the third spring rod length to keep that set where needed.

Sorry finger trouble

[DaveW]

The "3rd" rear spring shown in the picture strewn through this thread has a triple rate (at least). Ugly....

[RH1300S]

The "3rd" rear spring shown in the picture strewn through this thread has a triple rate (at least). Ugly....

I saw that as evidence of very specific tuning......

[speedsense]

The "3rd" rear spring shown in the picture strewn through this thread has a triple rate (at least). Ugly....

The top one, closest to the t-bar, appears to be a helper spring. Helper springs keep the sprung unit from rattling loose during extension, and are quite light in spring rate by comparison. This is likely a dual sprung unit, not a triple. IMHO

[RacingManiac]

The bar sticking down into the casing surely has a pivot point that affects the rising or falling rate of the third spring depending on it's angle relative to the angle of the spring body.

If there is an ARB it is well and truly hidden from view if it's there at all.

The tube is likely keyed/splined both end at the top of the "T" and at the base pivot(thats the proper way of doing it, in FSAE we just weld both end). You can swap out that bar with different OD/wall thickness to vary the rate that you want. Or go with a wider "T" to have more mechanical advantage over the bar itself. The Size of the tube can be as thick or thin based on your design. Looking at the bellcrank on the first pic the ARB is on a much greater motion ratio on the bell crank than the push rod. So a relatively less stiff bar will have a good effect on the wheel rate. The T is allowed to pivot back and forth on 2 wheel motion(heave, squat, dive..etc), and assuming relatively free movement the bar should have minimum bending(shorter bar helps too) to contribute to 2 wheel ride rate. The bar twists on roll to serve the ARB function. And as mentioned by the fact that the third spring is "pinned", it should not bend the third spring. On single wheel bump the bar will probably still twist and will add to the wheel rate. That is the issue with ARB in general as they do couple the otherwise independent wheels. A hydraulically based system like the Kinetics System used in some rally car(and possibly in F1)will be able to decouple that.

[RH1300S]

Guess what? - I still can't see how it works. You obviously have real life experience, so please bear with me.......

A normal ARB (std road car - across the axle and linking the wheels) will try and pick up the opposite wheel when in single wheel bump or roll. The tendency would be to try and lift the inside wheel off the road. It doesn't just transfer load by making the axle stiffer, but it literally moves load from one side to the other.

A normal road car system lets us have a fairly soft ride (heave if you like) and some roll stiffness. The trade-off is some cross-wheel effects on single bumps and also no damping on the roll bar spring.

In the system I am looking at if the vertical bar is a spring it simply adds to the wheel rate the same way in single wheel bump or roll. Any movement of the lever on the end of the pushrod is transmitted directly to the post whether in roll or bump (or am I being really thick?). So why not use the torsion bars attached to the lever along with their own dampers - it seems daft to add another spring in that arrangement. Also, as the car rolls one wheel moves up and it's partner moves down (assuming it has droop travel) - I would call that arrangement 'pro-roll' rather than 'anti-roll'.

Basically - given that this car has a separate 'heave' spring I can't see how/why an ARB is needed.

[RacingManiac]

Trying my best here with the pics...


Two wheel bump, the pic should be simple enough. Both wheel move, torsion bar twists, and 3rd spring compresses. The T-bar just pivots


Single wheel bump, the right wheel goes into bump, the right torsion bar twists, bellcrank pulls the the right arm of the T, which in turn will try to pull the ARB and the opposing wheel, much like a regular car's bar.


In roll, the red lines are the intended movement of the roll, and the yellow is the resistance offered by the bar, forgot to add the yellow lines for that obviously the individual torsion bars themselves will twist and resist the roll also.

[RacingManiac]

One of the odder design for a ARB though, goes to the Peugeot 908...

http://www.mulsannescorner.com/peugeot908-1.html

Though its certainly not the first odd ARB from them...

905: http://www.ultimatecarpage.com/pic/3291 ... Bis_6.html

[ringo]

How about the front of the F1 car?
Hardly seen any shots of that.

[mep]

The vertical tube is the anti roll bar.
Like the springs mounted in the bellcranks it is a torsion bar. This means when you try to twist it some force will resists against the movement. On the bottom is no big secret. Don’t invent some magical retarted ignition, blow suck antirollbar whatever there. There is just a kind of bearing which allows the top of the ARB to move in longitudional direction to the car when the heave spring gets compressed. What it does not allow is movement around the tubes axis. This movement leads to twisting of the tube and provides the required force against body roll. Apart from that there is nothing.

Will you need the ARB?
It’s not necessary but if you want to drive trough corners its better to have it. The two springs for left and ride side don’t help there very much. Why?
Imagine you have 2 springs coupled like seen on the picture both compressed but in equilibrium. Now you compress spring 1 this leads to decompression of spring 2. The force required to compress spring 1 releases spring 2. So in theory the force required to do so is quite low, yea you even have created a system that is able to oscillate. In reality the required force is quite high because the precompressed springs produce a lot of friction in your linkage. Furthermore you put dampers on both of your springs. So what happens now?
You can move the springs in every position you like and they will stay there!
It’s a quite nice effect but after your car body got into roll it will not comes back by itself until some force acts in different direction. It’s not a joke I have seen something like this on an American monster tuck once. Well it was quite funny for me to see the body staying in rolled even as the car went straight. Obviously the guy who made the truck had no idea what he was doing but he had to talk big words.
When you really don’t want to use an ARB then you remove the linkage between right and left side totally. This means you have a complete independent suspension and your body will come back from roll because both springs on the sides can decompress without compressing the other one on the same time.

[scarbs]

[Belatti]

Thanks Scarbs, nice pic!

Do you know wich car is it? Does it has an horizontal 3rd shock/spring? Are the pedals missing there?

[autogyro]

Interesting. Looks almost as if you could convert that to pull suspension.

[ringo]

cool man!

Interesting, first time i'm getting this kind of shot.

[Belatti]

cool man!

Interesting, first time i'm getting this kind of shot.

You should check gurneyflap