Suspension arms movements

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misterbeam
misterbeam
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Joined: 10 Mar 2015, 15:58

Suspension arms movements

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Hello,

Fews weeks ago, a friend made me notice that car from early 2000 era, had very minimal front suspension movements compared to late years cars! which made me question current cars ARB, spring rates ... we re they stiffer by the past or different building methods, or just softer tyres effect!

I would like to have your opinions on this!





Thanks!

EDIT: i think i got my answer

http://www.scarbsf1.com/wishbones.html

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PlatinumZealot
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Joined: 12 Jun 2008, 03:45

Re: Suspension arms movements

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My answer is this..

The large suspension movement that you in the 2015 car versus the 2002 car is because:
There are different requirements in ride-quality. The aero on the F2002 was probably less sensitive
The cars have different weight - A heavier car is better served with more suspension travel on the curbs (Curb riding is important in Canada).
The cars have different tyres, of which have their own spring rate and deflection.Possible that the F2002 is lighter and had a softer sidewall.
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mep
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Joined: 11 Oct 2003, 15:48
Location: Germany

Re: Suspension arms movements

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I have to admit I was a bit puzzled about the difference when I saw it, I was hoping to see some good replies but maybe they come now when we get that topic a bit more discussed.
First, I don`t think you found the answer on Scarbs page. It should not have anything to do with installation stiffness of different flex designs. Second, I also doubt it has anything to do with the points PlatinumZealot made. Talking about aero sensitivity is really speculative, the 2015 car could actually be less sensitive. Whereas, the 2002 car might have generated more downforce and therefore required a stiffer suspension. I also don’t think the weight plays a role here because compared to the downforce 100kg more or less is still a rather small difference.

I think that the 2015 car got particularly soft in in roll and single wheel movement while heave stiffness is still there. That allows seeing some wheel movement during cornering. This is achieved by a different design of the internal components of the suspension and better roll - heave decoupling. Maybe there is more anti dive geometry as well and maybe still something clever going on with roll coupling. Then less total downforce which allows to setup more for mechanical grip.

bhall II
bhall II
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Joined: 19 Jun 2014, 20:15

Re: Suspension arms movements

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misterbeam wrote:...we re they stiffer by the past or different building methods, or just softer tyres effect!

I would like to have your opinions on this!
My $0.01: I imagine it was probably a lot easier to bias setups toward aero stability, i.e. make it all stiff as hell, back when teams had the ability to run traction control, launch control, electronic engine braking, etc., to address aspects of performance that would have otherwise needed to be addressed with more compliant settings.

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PlatinumZealot
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Joined: 12 Jun 2008, 03:45

Re: Suspension arms movements

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mep wrote:I have to admit I was a bit puzzled about the difference when I saw it, I was hoping to see some good replies but maybe they come now when we get that topic a bit more discussed.
First, I don`t think you found the answer on Scarbs page. It should not have anything to do with installation stiffness of different flex designs. Second, I also doubt it has anything to do with the points PlatinumZealot made. Talking about aero sensitivity is really speculative, the 2015 car could actually be less sensitive. Whereas, the 2002 car might have generated more downforce and therefore required a stiffer suspension. I also don’t think the weight plays a role here because compared to the downforce 100kg more or less is still a rather small difference.

I think that the 2015 car got particularly soft in in roll and single wheel movement while heave stiffness is still there. That allows seeing some wheel movement during cornering. This is achieved by a different design of the internal components of the suspension and better roll - heave decoupling. Maybe there is more anti dive geometry as well and maybe still something clever going on with roll coupling. Then less total downforce which allows to setup more for mechanical grip.
Huh?!! Are you sure about that? Are you really really really sure? video evidence every weekend is showing otherwise...

Anyway... The video he posting was not a good demonstration of heave stiffness (front to back pitching) so I am not sure how you come up with that speculation.
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Tim.Wright
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Re: Suspension arms movements

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At a guess I'd say the springs are softer now to reduce the energy dissipated by the tyre due to road asperities in order to delay the degredation as much as possible.
Not the engineer at Force India

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DiogoBrand
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Joined: 14 May 2015, 19:02
Location: Brazil

Re: Suspension arms movements

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I remember watching F1 in the early 2000's when I was a kid, and I didn't even know at the time that the suspension had any movement :lol:. Now I see it wasn't just due to lack of knowledge.

Sixbarboost
Sixbarboost
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Joined: 12 Aug 2015, 16:33

Re: Suspension arms movements

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Tim.Wright wrote:At a guess I'd say the springs are softer now to reduce the energy dissipated by the tyre due to road asperities in order to delay the degredation as much as possible.
I agree, ten years ago with the Bridgestone vs Michelin tyre-war, you coould trust the tyres in a different way,
now you have to nurse them, why a softer suspension is needful.

Moreover, with the reduction in diffuser-height, downforce is less and no longer so sensitive to ride-height.

bhall II
bhall II
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Re: Suspension arms movements

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Sixbarboost wrote:Moreover, with the reduction in diffuser-height, downforce is less and no longer so sensitive to ride-height.
Reduced height makes aero more sensitive, actually. Just using arbitrary numbers here, but if a diffuser (or nose, for that matter) has a nominal ride height of, say, 15cm and suspension travel reduces that by 2cm, it represents a 13.3% reduction in the size of the "virtual duct" that exists between the component and the track. For a nominal ride height of 10cm, a 2cm drop is a 20% reduction.

That's the main aspect of pitch sensitivity, and it's the primary reason behind the initial introduction of high noses. They reduce the impact of variations in air speed/component capacity brought on by transient ride height changes.

DaveW
DaveW
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Joined: 14 Apr 2009, 12:27

Re: Suspension arms movements

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PlatinumZealot wrote:Huh?!! Are you sure about that? Are you really really really sure? video evidence every weekend is showing otherwise...
Anyway... The video he posting was not a good demonstration of heave stiffness (front to back pitching) so I am not sure how you come up with that speculation.
First, we are referring to the front suspension only.
Second, the heave/pitch stiffness is decoupled from the roll/warp stiffness.
Third, at some airspeed the heave/pitch stiffness becomes effectively rigid, to look after the aero.
Fourth, the development of FRIC showed the advantage of softening the front springs (see Tim's post).
Fifth, with FRIC now banned, teams would try to retain the ability to look after the tyres whilst also controlling the aero.

This would imply at the heave/pitch springs would be increased relative roll/warp springs, unless another way has been found to preload with heave/pitch springs without FRIC....

misterbeam
misterbeam
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Joined: 10 Mar 2015, 15:58

Re: Suspension arms movements

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So it's not due the left and right wishbones being linked together ? the lower arms looked really close to each other on the f2002 and even looked linked to me here :)

https://youtu.be/IsV29u8L8xo?t=2851

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PlatinumZealot
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Re: Suspension arms movements

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DaveW wrote:
PlatinumZealot wrote:Huh?!! Are you sure about that? Are you really really really sure? video evidence every weekend is showing otherwise...
Anyway... The video he posting was not a good demonstration of heave stiffness (front to back pitching) so I am not sure how you come up with that speculation.
First, we are referring to the front suspension only.
Second, the heave/pitch stiffness is decoupled from the roll/warp stiffness.
Third, at some airspeed the heave/pitch stiffness becomes effectively rigid, to look after the aero.
Fourth, the development of FRIC showed the advantage of softening the front springs (see Tim's post).
Fifth, with FRIC now banned, teams would try to retain the ability to look after the tyres whilst also controlling the aero.

This would imply at the heave/pitch springs would be increased relative roll/warp springs, unless another way has been found to preload with heave/pitch springs without FRIC....
I agree with all that. But read my post again and you will see that it was saying, that going by the actual video presented there is not enough material to conclude that heave stifness is still similar between the 2002 and 2015 cars as mep said. In fact i think other evidence shows that the newer cars have stiffer heave settings.
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DaveW
DaveW
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Re: Suspension arms movements

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PlatinumZealot wrote:In fact i think other evidence shows that the newer cars have stiffer heave settings.
Would you care to share that evidence?

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mep
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Joined: 11 Oct 2003, 15:48
Location: Germany

Re: Suspension arms movements

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misterbeam wrote:So it's not due the left and right wishbones being linked together ? the lower arms looked really close to each other on the f2002 and even looked linked to me here :)
Yes definitely not. The lower wishbone can have a shared mounting point and be even the same part but the flex separates them from each other.

Second, I said it is speculation to say one car is aerodynamically more sensitive than another. Unless there is some evidence I stick with that. The more sensitive car would need to have a more stable aero platform and therefore stiffer suspension. The other case is when one car produces higher amount of downforce, it will be run with stiffer suspension to support the forces to gain the max out of the aero performance and sacrifice mechanical grip for that.
PlatinumZealot wrote:I agree with all that. But read my post again and you will see that it was saying, that going by the actual video presented there is not enough material to conclude that heave stifness is still similar between the 2002 and 2015 cars as mep said. In fact i think other evidence shows that the newer cars have stiffer heave settings.
I did not say it is still the same, I said that it is still stiff in heave, could well be less than it was in 2002, which would make sense if the 2014 car has less downforce. The important point I tried to make is that the 2014 car got softer in roll and single wheel travel. That is what I think is visible in the video and it can be explained with developments made to separate heave and roll. BTW. heave and pitch are two separate movements. DaveW is the man who might know the actual numbers and what is right in the end.

I think that with the new engines and aero restrictions F1 moved from being aero dominated to something where powertrain plays a major role. This can also put more importance on mechanical grip. Mercedes has put a lot of effort into their suspension internals, they might have an advantage over the others. Btw. left to right linked dampers are still allowed.

DaveW
DaveW
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Re: Suspension arms movements

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mep wrote:DaveW is the man who might know the actual numbers and what is right in the end.
Not so, mep. I suspect that different teams have different strategies. I haven't seen any since the banning of FRIC.

ο»Ώ
mep wrote:I think that with the new engines and aero restrictions F1 moved from being aero dominated to something where powertrain plays a major role. This can also put more importance on mechanical grip. Mercedes has put a lot of effort into their suspension internals, they might have an advantage over the others. Btw. left to right linked dampers are still allowed.
That would be good news.