Please can someone explain how front suspension works in simple terms

[n1cecupoftea]

Hi,

Although I am not in any way technical I am a massive F1 fan.

I went to Autosport International today and whilst there I purchased what I was told is a lower front wishbone from a Renault R26. It definitely looks like the lower wishbone from the image at the link below:

http://www.gurneyflap.com/Resources/DeriveenVTS.jpg

However it is one single piece of carbon fibre, which has left me confused. My non-technical brain cannot understand how the suspension on each side can move independently if the lower wishbone joins the left and right wheels with one single solid part.

I have done a lot of Googling and although I found a great deal of information I still cannot get my head round how the suspension works now. The only thing I can think of is that in the case of the lower wishbone the carbon itself flexes, which seems unlikely and probably sounds like crazy talk.

I would be extremely grateful if someone could pretty please, with a cherry on top, explain in simple terms.

Sorry for being non- technical idiot and posting on a website called F1 Technical

Kind Regards,

Ray

[Tim.Wright]

It does flex.

At a guess I'd say they've been using flex joints on the inboard side for around 15 years now.

It's much lighter, zero friction and I'd imagine also stiffer.

[scarbs]

Thats a very nice part you have there. Post some pics.

Yes you are right, the wishbone does not have bearings as you would expect. but many f1 suspensions use what are called flexures, which are where the inner joint forms from the aero profile carbon fibre into a thin blade. it is this thin flexible blade that allows the suspension to move, all be it only a few millimetres.
These are used over bearings, as the installation is stiffer, has less friction and does not have issues with wear. however if the flex year is carbon fibre, it will need much inspection at the factory, if there's any overloads or damage the part needs to be scrapped .

[scarbs]

Thats a very nice part you have there. Post some pics.

Yes you are right, the wishbone does not have bearings as you would expect. but many f1 suspensions use what are called flexures, which are where the inner joint forms from the aero profile carbon fibre into a thin blade. it is this thin flexible blade that allows the suspension to move, all be it only a few millimetres.
These are used over bearings, as the installation is stiffer, has less friction and does not have issues with wear. however if the flex year is carbon fibre, it will need much inspection at the factory, if there's any overloads or damage the part needs to be scrapped .

[n1cecupoftea]

Thanks both for your replies. I am still confused, apologies.

Please see photographs below:






One joint is almost all carbon fibre with only a small amount of metal around the mounting holes. The other one is carbon fibre with a metal plate on the back. Neither seem like they would flex but I am probably wrong.

[Greg Locock]

Here's an earlier example of a leaf spring used as a lateral arm. Another innovation by F1?



dunno why that doesn't work

https://en.wikipedia.org/wiki/Leaf_spri ... _1935).jpg

[roon]

This design looks like it may rely upon flexing along the entire length of the arm, rather than using shorter, discrete flexures which the others have mentioned. It might help to imagine a diving board, for comparison.

[Webber2011]

Great purchase mate !

Your pictures have me intrigued now

Can anyone answer this question please ?

There's a multi pin connector in your third photograph.
Is that for sensors, or something else ?

[roon]

For sensors in the wheel uprights. Notice the two smaller counterpart connectors sprouting from the ends of the arms.

[n1cecupoftea]

Thanks very much to everyone for all your help; I think I understand it now

I have been having a closer look at the wishbone this morning and noticed that there seems to be a material change, or at least a colour change, near to the point where the wishbone would connect to the car itself. Please see images below showing this:







It looks like the carbon fibre on the inside is more dense than the carbon fibre on the outside but that could well be absolute rubbish . Is this related to the flexing at all or is it completely irrelevant?

[n1cecupoftea]

Sorry; duplicate post

[n1cecupoftea]

Thanks to everyone for all your help, it is much appreciated. I think I understand how it works now.

*I did post a more detailed comment with some additional photographs but it doesn't show. I am guessing it needs to be approved by a moderator. I tried twice so apologies to the moderators if you have two very similar posts sent to you for approval!*

[scarbs]

Interesting. I think the flexure is there inside the carbon. It looks like the arm is the same profile across its length, but you can see the carbon weave changes colour about 10cm from the centre mounting, its probably inside this thinner outer fairing section. So it should sound hollower than the rest of the arm if tapped.

[n1cecupoftea]

Thanks again scarbs.

I just tapped along the length of the carbon and it doesn't seem to sound more hollow at any point. However what you are saying does make sense.

[Tommy Cookers]

Interesting. I think the flexure is there inside the carbon. It looks like the arm is the same profile across its length, but you can see the carbon weave changes colour about 10cm from the centre mounting, its probably inside this thinner outer fairing section. So it should sound hollower than the rest of the arm if tapped.

is it possible that the different areas mentioned around 10cm 'in' are for controlled wishbone frangibility serving crash requirements ?
and the flexural regions not so apparent to view ?

though right now I tend to agree with roon's suggestion - (that the compliance is somewhat dispersed as the diving board example)
certainly this is plausible with cfc for various good reasons
remember eg GM successfully introduced the grp rear spring/'wishbone' on the Corvette from 1981, and such are quite common today
https://books.google.co.uk/books?id=NC- ... ng&f=false

one would expect a flexural region to be thinner than the typical wishbone section even with cfc ?
(having designed various metal flexure applications in the past)