How do the front wheels of an F1 turn?

[Guest]

this is a bit much to be answered in a single post...
First you have to understand that the car is connected to the road via the tyre contact patches.If you can maximise these contact patches over the cause of the race distance you have exploited the maximum .Aero helps to push the car firmly to the ground increasing the max grip.Suspension geometry makes sure the tyre has maximum contact to the road at all times(dampers ,springs and stiction effects as well as outward influences l allowing)
the obvious parameters are camber ,Caster ,toe.with camber you lean the tyre inwards at the top,compensating for the lean of the car body when cornering,trying to keep the tyre contact patch maximised .
static camber reduces the forward and braking ability of the tyre,so you don´t want to go overboard there.
And you don´t want too much lean (roll)in the car to keep the Aero working.(that´s why they are paranoid about CG height ).
Camber is not constant with suspension travel if your suspension top and bottom wishbones are not the same length and parallel.This is called cambergain.Wishbone lengths and positions in and outboard heavily influence all this ,the intersecting lines determine the effective swingarmlengths with corresponding rollcentres.....
Of course these effects are all more pronounced with increasing suspension travel and one might argue dampers and tyres are more of importance then geometries in F1.
I will elaborate on Caster KPI Casterlead and offset if you are interested.
Ackermann is a whole new story if you really fancy to know about...as is antidive or antisquat.
marcush.

[Monstrobolaxa]

this is a bit much to be answered in a single post...
...marcush.

Well in any case you did sumarise it...in a understandable way!

[Alic01]

I knwo this post is not directly related to the power steering system but i was working on a job with Moog on Tuesday and got the data sheets for there motorsport products.

Just to add a little ifo the link below shows the power steering system developed for F1 by Moog you will see that it is a completely bespoke piece fo kit. You feed one pressure in and the rotation of the steering column directs it to either the left or right of the power steering servo.

http://www.moog.co.uk/Media/1/RPSDataSt.pdf

Also worth a look is the gear selector with a response time of 3ms which can be found at http://www.moog.co.uk/Media/1/E050GearboxV.pdf

I dont know the exact technicalities of F1 (althought through you guys im learning).

[mep]

The cambergain, explained by marcush could bee another reason for
twin keel suspension because the lower wishbones is shorter than the uper one.
At a single keel suspension the lower one is longer than the uper one.





"I will elaborate on Caster KPI Casterlead and offset if you are interested"

I don't realy know what you mean, but why not?

[Guest]

so here we are ..Twin Keel nonsense.Right the upper wishbones are longer than the lower ones.what happens to the wishbones during thetyres motionfrom full droop to full bump?going in bump the suspension gpoes into positive camber...bad news.
with the wheel going in droop the camber goes intonegative ...Because of that williams angles the top wishbonesdownwards to counteract the negative cambergain in bump...BUT they get huge trackvariation(scrub)
with this.accordingly the williams when setup soft will be fast over a single lap but eat his front tyres at an alarming rate.Williams seems to setup the car very stiff at the front to avoid big wheelmovements ,minimising the unwanted scrub at the expense of compliance.So the aero improvement destroys the mechanical side of the thing.
Mclaren chose a different route to counteract the unwanted positive cambergain with KPI angles imo.

As for the KPI caster things... I would explain if someone is interested and you seem remotely interested ,are you?

[bernard]

I found a nice close-up:

[mep]

As for the KPI caster things... I would explain if someone is interested and you seem remotely interested ,are you?

Of course, I'm interrested.
I think it would help to understand how the differences in singel and twin keel suspensions are. I want to understand the the mechanical grip in all details.

[bernard]

so here we are ..Twin Keel nonsense.Right the upper wishbones are longer than the lower ones.what happens to the wishbones during thetyres motionfrom full droop to full bump?going in bump the suspension gpoes into positive camber...bad news.
with the wheel going in droop the camber goes intonegative ...Because of that williams angles the top wishbonesdownwards to counteract the negative cambergain in bump...BUT they get huge trackvariation(scrub)

ummm... Isn't it exactly the other way around? Single keel: upper wishbones shorter than the lower ones, that go to the keel under the car.
Twin keel: same length wishbones as the twin keel is as wide as the nosecone.
So your whole argument was based on false accusation. It is therefore inaccurate. The negative effects you described exist in single keel instead of the twinkeel you mentioned.

[Reca]

Twin keel: same length wishbones as the twin keel is as wide as the nosecone. So your whole argument was based on false accusation. It is therefore inaccurate.

In the Williams FW26 (the car the guest was referring to), the keels have an inclination towards the wheels making the lower wishbone shorter than the upper one.

The negative effects you described exist in single keel instead of the twinkeel you mentioned.

The negative effect the guest described was the positive camber gain in bump, it does happens the same, in your opinion, with a single keel setup ?

[bernard]

In the Williams FW26 (the car the guest was referring to), the keels have an inclination towards the wheels making the lower wishbone shorter than the upper one.

The guest was saying "so there we are... twin keel nonsense" based on observations of a twinkeel setup with shorter lower wishbones, but this is not true of all twinkeel setups, so the whole concept of twin keel can't be regarded as crap based on problems existing in a certain solution. This is what I was saying. Pay attention.

The negative effect the guest described was the positive camber gain in bump, it does happens the same, in your opinion, with a single keel setup ?

The effects the guest mentioned are true of a setup with different length wishbones, so they don't exist in twinkeel with same lenght wishbones.

[marcush.]

sorry .
I just wanted to say:you should not think aero is king and everything else is of minor importance.
BTW Mclaren seems to field a quite capable Twinkeel car these days....my honest admiration on that achievement.

[Reca]

The guest was saying "so there we are... twin keel nonsense" based on observations of a twinkeel setup with shorter lower wishbones, but this is not true of all twinkeel setups, so the whole concept of twin keel can't be regarded as crap based on problems existing in a certain solution. This is what I was saying. Pay attention.

The twin keel designs currently existing in F1 (McLaren and Williams) have the lower wishbone shorter than the upper one. The teams that in the recent years used almost vertical twin keels reverted to a single keel setup because the aerodynamic advantage of the previous setup wasn’t worth it and to follow the McLaren and Williams route, the only one apparently worth a try, is too difficult for them, especially for the compromises and particular structural design and suspensions geometry it requires.

The effects the guest mentioned are true of a setup with different length wishbones.

There’s a little difference in the suspension behaviour in bump comparing a setup with the upper wishbone longer than the lower one and a setup with the lower wishbone longer than the upper one. I can lend to you my magnification lens if you don’t see it

[bernard]

bernard wrote:

The effects the guest mentioned are true of a setup with different length wishbones.


There’s a little difference in the suspension behaviour in bump comparing a setup with the upper wishbone longer than the lower one and a setup with the lower wishbone longer than the upper one. I can lend to you my magnification lens if you don’t see it

well perhaps you should use it yourself. I said the effects the guest mentioned are true in a suspension setup with different length wishbones, so they don't apply to a setup with the wishbones the same length.
Now, I'm thinking, how can i say it so that you understand it and don't have to come whining about it.
Ok, I'll say it to you in Italian, or whatever the hell it is you speak there.
La partiente elemento la posto ferrari.
There, hope you understand me now.

[Guest]

Arrows twinkeel.
picture taken from scarbsf1.com

[Reca]

I said the effects the guest mentioned are true in a suspension setup with different length wishbones, so they don't apply to a setup with the wishbones the same length.

Again... what you said :

The negative effects you described exist in single keel instead of the twinkeel you mentioned.

The way I read it, is that with a single keel you have the same negative effect you have with a twin keel in the case of unequal length wishbone. That negative effect, the one marcush was referring to, is the positive camber gain in bump.
But, when the lower wishbone is longer than the upper one, as with the single keel design, there’s a negative camber gain in bump and that’s usually a positive effect, not a negative one as you said.
With a twin keel, also with same length of the wishbones, you don’t have camber variation (so you lose a positive effect) and, even worse, if the lower wishbone is shorter than the upper one (as in all the current twin keel designs, the Arrows A23, as surely the “guest” knows, is a 2002 car...) you have the negative effect of a positive camber gain in bump. That’s the one marcush was referring to, and you don’t have it with single keel.

La partiente elemento la posto ferrari

the starting (actually partiente isn’t Italian but I assume you wanted to write partente) part I place it Ferrari ??
Je pense qu’il est mieux si tu parle Français parce que ton Italien n’est pas vraiment compréhensible.