The relative benefits of a pull rod suspension

[hankalis]

Well if you considered they changed the geometry. You can say it was not optimal in the beginning.
I don't mean a little setup change like most teams do, but a whole new upright is a drastic change.

Those pictures show well how redbull's upper control arms are fairly level compared to the new A arms for the ferrari.
We can look on the angle of the pushrod as well. It is compromised by the small volume it has to crammed into on top of the gearbox.

Ferrari were lacking in the geometry, and made some changes to improve it.
Haven't seen much change with the redbull or Mclren in terms of new uprights to move the outer joint up by an inch.

According to Scarbs the change of rear suspension's geometry has more to do with the way tires are (mechanically) worked than aero benefit
http://scarbsf1.wordpress.com/2011/07/1 ... e-upgrade/

Yes, but this is because they forced the pusrods' bell cranks to be much closer to the center of the car and also with a agressiv forward sweep. This was for aero reasons, but it affected the mechanical side of things due to the rod angles. If you follow what I am saying.

The pull rod being near the base of the car which is wider, doesn't have this issue.
Reading the regulations it can be seen that after a certain height the body works narrows. The higher the suspension the more it obstructs this narrow and smooth body.
Last year's W01 had 2 ugly bumps on top of the bodywork. Ferrari avoided this by pushing the cranks further to the center.

yep.
but what I found interesting is that making a change that consists of compromising aero in favor of better mechanical behavior ... is resulting in a clearly net positive impact.
just shows that off course aero is critical to car performance but making tires work properly (which takes more than just increasing downforce) is as important.
making the choice of suspension configuration less trivial!

[RacingManiac]

Yes, but this is because they forced the pusrods' bell cranks to be much closer to the center of the car and also with a agressiv forward sweep. This was for aero reasons, but it affected the mechanical side of things due to the rod angles. If you follow what I am saying.

The pull rod being near the base of the car which is wider, doesn't have this issue.
Reading the regulations it can be seen that after a certain height the body works narrows. The higher the suspension the more it obstructs this narrow and smooth body.
Last year's W01 had 2 ugly bumps on top of the bodywork. Ferrari avoided this by pushing the cranks further to the center.

Not sure how you can actually say that for certain, as Scarb's guess(which is probably as good as yours, since they are all just guesses), mentioned they were doing it to play with rear tire scrub, which in my rather laymen understanding of kinematic can be done without much contribution to push/pull rod location(which from a suspension point of view, is just motion ratio, be it as pull or push rod), as much(if not all) of that is driven by location of ball joints and tie rod. And his reasoning is sound in that again due to the lack of actual data from not running the Pirelli, they chose to go with something that might preserve tire, which ends up biting them since they are not aggressive enough on them.

[PlatinumZealot]

word on the street ferrari switching to pull-rod for 2012.
No brainer? let us see.

[ringo]

for a set of regulations there is one theoretical ideal and the other teams are willing to approach that at all costs. Ferrari have not yet made it clear why they deviated from the assumed ideal.

If you are given a set of rules to follow, and then asked to find a goal. Those rules will guide you to a simplified universal solution. All iterations will converge to one given enough reptition. This is why from 2009 cars begin to look the same every year.

I think we can all agree on this after a year of blantant copying of the best car.
I hope the debators in this thread view things differently now.

Ferarri and their pushrods failed as predicted. They were stubborn. It wasn't about what was the best solution.

I like to bury the hatchet in these kind of threads. Can everyone who took part return and summarize what we witnessed this year while bringing up some old points that now need to be tested by what happened in the now future.

[ringo]

Au contraire, I think you will see more push rods next year, as teams has by now realized that packaging and adjustment of the pull rod is a nightmare, while CoG and aerodynamic gains are minimal.

And you can quote me on that one.

Ferrari are coming with an extreme solution. What can we expect?
They don't have much experience with pull rods as the other teams. They have issues getting pace out of the hard tyre.
How will they approach 2012, when other teams have done thousands of km on their pull rod suspensions?

[raymondu999]

Actually Ringo most probably there is not 1 optimum, but maybe 2 or 3; in the same way an equation could have more than 1 "zero." But that would probably mean going in an entirely different direction. For example if you super-refined the McLaren U-pods it possibly could have the same performance peak as the Red Bull shrink-wrap sidepod, over the course of a season. If for example you want to go the more conventional route like Ferrari did; which is kind of a similar direction to Red Bull, then a pushrod wouldn't be optimal. For single races, there's probably 1 single optimum setup, driving style, and car design when you're looking for that very last thousandth.

[ringo]

What has this year shown?

One car with 2 championships and 18 pole positions out of 19.

No other car came close to it's dominance. If there were 2 or 3 optimimus, i never saw it this year. In fact never saw it in F1 before.

As for the Mclaren U pods, there is no super refining. The minimum radius rules says 75mm. That alone is a barrier to refinement. The leg of the U can be no thinner than 75mm.
So you see you have to be mindful of the rules before you assume all features have equal potential.

Its sounds boring, but different design paths cannot yield the same maximum results.
The shape of a bullet, a passenger plane, a knife, a computer screen, a nail ect are examples of converged designs. As time progresses and the knowledge base grows, the same will happen to F1 cars. Engineers will know all the dos and don'ts in each regulated volume.

Ferrari's experience has grown now, and they will conform the rear suspension i think.

[DaveW]

What has this year shown?

One car with 2 championships and 18 pole positions out of 19.

No other car came close to it's dominance. If there were 2 or 3 optimimus, i never saw it this year. In fact never saw it in F1 before.

That is quite a record, which you put down entirely to the pull rod rear suspension? You might find that a bit of a hard sell to the competition (all but one of them has a pull rod rear, I think).

Part of the reason for iterating towards similar design solutions is the fear of being blamed for failure (it is very easy to conclude the any deviation in a design is the cause of lack of performance). Copying is cheap but it does help to keep the wolves at bay.

[hardingfv32]

"Part of the reason for iterating towards similar design solutions is the fear of being blamed for failure (it is very easy to conclude the any deviation in a design is the cause of lack of performance). Copying is cheap but it does help to keep the wolves at bay."

IN F1! Tell me it ain't so.......

Brian

[PlatinumZealot]

The predictions are close to coming true!
Rumored to be Pull rod on F2012
http://www.jamesallenonf1.com/2012/01/s ... ri-f1-car/

[PlatinumZealot]

The ferrari is also said to have front pull-rod suspension like the 2001 Minardi.

http://scarbsf1.files.wordpress.com/201 ... t_view.jpg

[raymondu999]

The ironic thing is that Aldo Costa was in charge of that 2001 Minardi.

[shelly]

I think Costa was at Ferrari already in 2001, and the TD at Minardi was Tredozi

[aleks_ader]

I think Costa was at Ferrari already in 2001, and the TD at Minardi was Tredozi

No i am quite sure that main designer was Gustav Brunner and tehniacal director was Tredozi... Tham in imediatly in that 2001 season Toyoda hired Brunner...

[PlatinumZealot]

Some pictures of this "beast"..

http://www.f1fanatic.co.uk/wp-content/u ... 2012-2.jpg



Strange... that's a really shallow pull rod angle.. the motion ratio must be a scarifice.

The rear:

http://i.imgur.com/cbW27.jpg