Tech talk

[Mr Kurtz]

I like F1 because I basically love fast cars. But I'm fascinated with the technology and for me that makes the other half why I watch it. But unfortunately you can't always see the 'real' differences between the cars. So I thought that if you guys see great pictures from the different rear suspensions etc you could post them here.
Reviewing some pictures from testing, I noticed that there are distinct differences in the front suspension of the teams. Toyota and BMW have upper wishbones that are going up closer to the car, Ferrari and Mclaren for instance have horizontal upper wishbones and if you look at the Renault, they're going downwards. I wonder what works best with the new Bridgestones.

BMW : http://images.gpupdate.net/large/68404.jpg
Toyota : http://images.gpupdate.net/large/68397.jpg
Ferrari : http://images.gpupdate.net/large/68401.jpg
McLaren : http://images.gpupdate.net/large/68399.jpg
Red Bull : http://images.gpupdate.net/large/68398.jpg
Renault : http://images.gpupdate.net/large/68400.jpg

[tinchote]

I know little or nothing about all this. I wonder whether those angles you mention are a fixed feature of each car, or they can be altered for different setups.

[wmcot]

I see what you mean from the pictures posted. I would love to hear from someone who is knowledgeable about this subject! It's refreshing to actually LEARN something from these forums...

[Gannex]

The angle of the wishbones is determined by two factors: the method of mounting the lower wishbone, and the height above ground of the forward monocoque.

The big decision is whether to have zero-keel, twin-keel, or v-keel as mounting for the lower of the front wishbones. This has been one of the big issues in F1 design ever since Sauber stunned the F1 world with its twin-keel design about five years ago. Until then, every car had the lower wishbones attach to a single keel under the monocoque. This was a very rigid arrangement (rigidity is good) and light in weight as well. But it placed a keel (and the wishbones themselves) directly behind the front wing, spoiling the airflow behind the front wing, and thereby reducing the downforce of the wing, as well as increasing the drag. That is why Sauber developed a twin keel arrangement: it left a tunnel behind the front wing, smoother airflow and higher downforce.

But a twin-keel arrangement had a severe problem: it flexed. To eliminate the flex (which changes suspension geometry by very small amounts, and therefore sacrifices control of the contact patch of the tyres), designers found they had to beef up the two keels. Beefing them up made them heavier and larger, meaning you move the centre of gravity of the car forward, and you increase the drag associated with the keels themselves. So Sauber's innovation was not copied by everyone, Ferrari being the most notable hold-out.

By 2005 or so, almost everyone had moved to some version of the twin-keel arrangement to take advantage of the improved downforce at the front and the smoother airflow toward the rear of the car, under the monocoque. Call these arrangements twin-keel or V-keel, or whatever, the fact was that they allowed the lower wishbone to be mounted the same height above ground at both ends: at the keel, and at the wheel. This gives you a horizontal lower wishbone which, in a perfect world, is exactly what you want.

Adrian Newey, however, found a better way, and it made its debut on the 2005 McLaren. It did away with the keels altogether, anchoring the upper wishbone into the monocoque (hardly revolutionary), but anchoring the lower wishbone into the monocoque as well !!! This could only be done by lowering the droop of the nose, and even then, the lower wishbone was slanted upwards to meet the monocoque, rather than parallel to the ground, as it would have been if it had been anchored to a keel. That's why the 2005 McLaren was the first car to have droopy front suspension linkage: high at the centre, sloping downwards towards the wheels.

The McLaren zero keel was a bold breakthrough design, and its obvious advantage was that there was now no keel at all, no superstructure at all interfering with the airflow behind the front wing. Even the V-keel arrangements had some disruptive effect on the front wing exiting air, but the zero-keel let that air flow smoothly and quickly backwards -- exactly what you want.

But what about that droop that a zero-keel imparts? Is that not a problem? Suspension settings indeed become very difficult. Keeping the contact patch large during all conditions becomes increasingly complex, and this is the large drawback to the zero-keel design: it makes front suspension set-up very difficult. If it's correct for a fast corner, it's incorrect for a slow one. As the car rolls (i.e., rotates around its longtitudinal axis), controlling the effects of the roll become infinitely more complex. McLaren were initially alone in having the zero keel with its droopy suspension.

But not any more!!! Everyone and their brother seems to have seen the Newey light. Even super-conservative Toyota now have a zero keel arrangement on their 2007 car. So the F1 car, in its standard configuration, now has droopy front suspension wishbones, and each design deals with this problem in a different way. Note the complex kinks in the Toyota wishbone, for example.

There are two exceptions to this design trend and the most surprising thing is that the designer who has most clearly rejected zero-keel is the very man who invented it, Adrian Newey. This year's Red Bull, which is Newey's design, goes back to twin keel, meaning that Red Bull has its suspension wishbones nice and parallel as nature intended.

The second design to go against the zero-keel trend is Renault. They have a V-keel arrangement, so that they too will benefit from the logical suspension geometry that you get when you don't have to slope your lower wishbone upwards to meet the monocoque.

These new suspension arrangements have to work, of course, with a totally new construction of front tyre, and it is here that the dissidents, Renault and Red Bull, might have hit the jackpot. Winter testing with the new Bridgestone tyres has shown that they, especially the fronts, are extremely low in grip compared to last year's tyre. Bridgestone have been quite honest about it, admitting that the construction is designed to sacrifice grip for sturdiness, reliability and safety. But the drivers are finding it very difficult to adapt to this year's Bridgestone fronts. Braking distances, for example, have had to be extended massively, to avoid front-wheel lock-up.

So with the new Bridgestones it appears that a straightforward front geometry becomes even more important than it was last year. At that very point, all the teams except Red Bull and Renault have moved onto droopy suspension arrangements, zero-keel, which makes suspension set-up tricky. That's why Red Bull and Renault's return to conservative old-fashioned suspension geometry might have come at exactly the right moment.

[Roamy]

gannex

this is very very good stuff !!!!!!!!!!

[Gannex]

Why thank you, fousto. And you said that even though I made not one reference to JV's genius!

[mstillhere]

That's what I call a detailed information.

[mstillhere]

That's what I call a detailed information.

[mstillhere]

That's what I call a detailed information.

[mstillhere]

Sorry for the multiple postings. I had a little issue with my browser.

[RJL25]

nice post gannex.

I think a telling bit of evidence is the fact that adrien newey is the "father" of zero keel suspension designs, so the fact that he has turned his back on his old child in a sense to go back to a twin keel for this year tells me something, that being that these new bridgestones are going to need that extra adjustability that a zero keel design simply cannot provide.

On the original post i was quite shocked to see renaults design! The upper wishbone was on a completely different angle to everyone elses. Now to my, albiet very limited, understanding of suspension and how it works, i would have thought that the renault design wouldnt pass enough energy onto the front wheels, therefore making the chassis work harder then it needs too, and therefore making the front end roll around more then the other designs would, meaning that renault would have to setup their front suspension to be quite stiff... But then the renault guys are pretty cluey so im assuming they know what they're doing, but still...

[Sleeper]

Very nice post Gannex, but a few things:

Twin keel was only ever used by four teams (as far as I know), Sauber (who droped it by 2004), McLaren (who replaced it with zero keel), Jordan/Midland/Spyker (who have only just made the change to zero keel this year) and Williams (who droped it after only using it for 2004). I think that the problem with twin keel was not that it moved the weight forward (something the teams try to do normally due to the undersized rear tyres) but it moved the weight slightly higher up on the car, not a good thing. Moor importantly, all four teams found that it had a large negative effect in making the car pitch sensitive on turn in.

The problem with zero-keel is that the lower wishbone is no longer horizontal and results in a reduced ability to adjusted the cambrer of the wheels. This proved to be little problem on the Michelins as they had a flexible side wall construction and stiff tread making up for the lack of camber adjustment (sadly this resulted in Indy 05 as well). However the Bridgstones have a much more ridgid side wall construction and flexable tread ( the opposit of Michelin, it has something to do with the fact that the majority of Michelins grip was derived chemically and Bridgestones mechanically, though they moved closer together over the last couple of years) meaning that they need more camber adjustment in the suspension. As ar as I'm aware this was part of he reason for Toyota having such a terrible start to last year, they were running zero-keel for the irst time and ha a late swich to BS tyres. However it does now appear to be possible to work around this, I read in Autosport that the very high ixing point of the upper wishbones on the Toyota and BMW, as well as there bendy shape, was to try to increase the camber adjustment range and McLaren isnt having any problems in this area that I'm aware of.

With Red Bull, what they now employ is not really a twin-keel set up but more of just a couple of stuby attachment points on the underside of the monocoque. I cant tell from any pictures that I have sen but I dont think the lower wishbones are exactly horizontal, but are closer to it than other teams using the set up. What has really surprised me this year is that Ferrari have switched to zero-keel from single-keel. It does ask the question, have they got it wrong or do they know something about how the tyres work that the rest dont?

Its also worth notocing that, as far as I know, Honda are the only team still using the single-keel layout (though that probably means so will Super Aguri), while Renault are sticking with the V-keel layout, that I admit I know nothing about.

[ClarkFan]

Gannex - thanks. A very interesting exposition.

It will be interesting this year to see who complains of lack of front end grip and whether the compliants track to suspension anchoring decisions.

ClarkFan

[Gannex]

Thanks RJL25 and Sleeper for the additional thoughts and information. Very interesting, and I agree with you, ClarkFan, that this season is shaping up to be one of the most unpredictable and fascinating ones for many a year, in part because of the suspension/tyre issues that Mr Kurtz brought up.

Sleeper, I find it frustrating that we don't get to see the underside of the cars as they are released. We get to see liveries in excruciating detail, but when it comes to useful photos of design details, those seem to be completely off limits. The aero bits at launch are just for show, and bear little relationship to what will be on the car when it races, and the suspension, both front and rear, usually remains hidden. Why can't they show us pics of the cars with the wheels removed? It's not as if their competitors can't see that; it's only us, the fans, who are kept in the dark.

[tinchote]

Great thread, guys! :)

[harsha]

could the reason for Williams performance in 2004 be actually down to using Twin Keel and not due to the walrus :?:

[Mr Kurtz]

the different keel configurations:

[fly_ac]

this is from another forum

......for those who like pictures :D

[fly_ac]

this link give some pics too. ;)

http://www.scarbsf1.com/keels/formula_1_keels.htm

for those who like pics. :D

[Robinho]

great information guys, particularly Gannex, the Keel situation is something that i've heard a lot about and understood little but i think i'm a lot closer now. it will be interesting to see what is the right way to go, i have also seen a lot written in Autosport etc. about the reason for which is the best way and the reason the teams are reverting back from previous ideas, predominantly due to the difficulty in getting heat into the harder front tyres

[donKey jote]

fascinating, thanks guys :)

[Mr Kurtz]

So anybody notice anything fascinating about other parts of the cars? Anybody has some information on those seemless shift gearboxes for example?

[CaptainRaiden]

Now, I can post some Interesting pics which illustrate the Keel Setups better. Here :

The first one is a diagram, albeit a very crappy one, but you get the idea :

http://www.scarbsf1.com/keels.jpg


The Twin Keel Setup on a Midland

http://www.motorsport.com/photos/f1/2006/fra/f1-2006-fra-xp-0304.jpg



The Single Keel Setup on a Ferrari

http://www.motorsport.com/photos/f1/2006/fra/f1-2006-fra-xp-0306.jpg




The V-Keel Setup on a Renault

http://www.pitpass.com/images/galleries/2006testjerezjan1014/2006testjerezjan1014_s279.jpg


And Finally, a Zero Keel Setup on a Toyota :

http://www.motorsport.com/photos/f1/2006/ger/f1-2006-ger-xp-0185.jpg

[RJL25]

nice summary to the discussion X-ecutioner, i think it sums everything up nicely

how about rear suspension tho? Is that dramatically different from team to team? or is everyone more or less doing the same thing? Is there very much room left for innovation in rear suspension design? I think its fair to say that the only real reason they're is still innovations in front suspension design is because front suspension has such a major influence overy aerodynamics, and therefore finding a compromise between optimum suspension setup and aero efficiency drives that innovation forward. But without the same aero influence over rear suspension have we pretty much reached the peak of rear suspension innovation???

[CaptainRaiden]

Correction, I'm sorry that's a V keel setup on a Renault. I posted Twin keel. My bad. :(

Corrected!

[CaptainRaiden]

nice summary to the discussion X-ecutioner, i think it sums everything up nicely

how about rear suspension tho? Is that dramatically different from team to team? or is everyone more or less doing the same thing? Is there very much room left for innovation in rear suspension design? I think its fair to say that the only real reason they're is still innovations in front suspension design is because front suspension has such a major influence overy aerodynamics, and therefore finding a compromise between optimum suspension setup and aero efficiency drives that innovation forward. But without the same aero influence over rear suspension have we pretty much reached the peak of rear suspension innovation???

Now I’ll try to answer with whatever I know. More technically sound members like Gannex or Sleeper, Correct me if I’m wrong.

I believe the Rear Suspension Design pretty much depends on how the front Suspension is set up. For example a rear suspension setup for a front zero keel will be different than that of a Twin keel setup. It also depends on how much mechanical grip is available so that the car doesn't slide while cornering. The complete suspension arrangement of the car includes the front and rear suspension. It also depends on a whole lot of other factors, Most importantly proper management of Camber angle on the front tyres to decide how much cornering speed or straightline speed the car should have, How much downforce does the car generate, Weight distribution, how long is the wheelbase, The Anti-Roll Bars etc. etc.

Now as far as weight distribution goes, the best example(although not proven) would have to be the Ferrari F2007 with a longer wheelbase and hence a longer front profile than any other team. Many Insiders believe that Ferrari know something about the new Bridgestone tyres that the other teams don’t, and that’s why the car is 10 kgs heavier than last year with the majority weight distributed towards the front to avoid Grip loss and tyre lockups while cornering because of the new slippery tyres. Probably One of the major reasons why Ferrari adopted the Zero keel this time around. And So the rear suspension for the New Ferrari is also Heavily revised for this year because of the new front layout. They might’ve hit the sweet spot with this but, We may never know this until we see the first race.

So in short, the doors for innovation in rear suspension are always open, but they have to work in conjunction with the front setup, otherwise say goodbye to your car’s overall Balance. I hope I have answered your question. And if I’ve screwed up somewhere, somebody please correct me. ;)

[Sleeper]

Nice pictures X-ecutioner, its the first time I've properly seen the V-keel layout. It looks like its an attempt at a compromise solution to me as basically there are four thin carbon struts there (two from the suspension and the V section) which offer reduced interferance with the front wings wake whilst maintainig the optimum suspension geometry of the single keel. As Renault have won the last couple of titles I guess it cant be a bad system overall. I also read at the start of last year that Ferrari had adopted the system on thier car, but on the launch of this years car I hear they were actually using a single keel layout so I'm a bit confused on that area.

I'm not actually sure whether there's any significant corelation between front and rear suspension setups i.e. that you do one thin to one end and you have to have a specific performance from the other.

One thing that I do know is that the rear suspension does get a lot of development on it, an I think we'll probebly see more of it this year with the very fragile rear tyres that we have now. I know that Ferrar has for most of this decade been using a special rotary damper system on thier rear suspension (developed in conjunction with Sachs, exclusively for Ferrari), and Toyota has develepod their own version in the last few years but with a third, central damper (its this central damper that gave them a lot of trouble last year, it failed on both cars within a few laps of each other in Brazil last year with both cars coming into the pits with the back en on the ground). Sadley, I dont actually know the significance of going with rotary dampers, all I know is that they absorb shocks by twisting but their strengths and weaknesse as well as how their performance differs to conventional dampers is unknown to me. In recent years using the top strut of the rear suspensionas an aerodynamic aid has been the main line of development. For 05 when the rules governing diffuser shape were changed, reducing their effectivness, Renault designed the rear top strut of the rear suspension and the lower beam wing of the rear wing to act in conjunction with the diffuser, effectively making it longer and getting a better venturi effect, which= moe downforce, than their rivals.

This years Ferrari is deinitely a very strange design, even if it looks a lot like last years. As I said in my previous post, the single-keel layout is known to work best with Bridgestone fronts but Ferrari have switched to zero-keel this year. More importantly is that the rear tyres are more fragile this year and wear faster so most of the teams have been working their backsides off getting the waight distribution forward on their cars (McLaren's was always a very forward biased car which probably goes a long way to explaining why their so fast in testing so far), yet Ferrari have lengthend their wheelbase and moved which has moved the weight distribution back going completely against the conventional train of thought. There seems to be two possibilaties for this: Ferrari have the best simulation technology in F1 at the moment and have worked very closely with BS for a long time so its very much possible that they know something the rest dont about the tyres and how they work (as you can imagine, this has the other teams scared sh!tless as we all know what happens when Ferrari steal a march on the others), or the new design team are so keen on proving themselves that they decided to throughaway the old design and start new to prove themselves, but have actually got it very wrong. As they arent looking to hot in testing at the moment, and some of the long standing, senior technical staff arent, apparently, too happy with this (like Nigel Stepney) I'm thinking the later might be right.

[tinchote]

Hey, Ferrari was at the top of the sheets today, so now it is certain that they will win the championship ;) :D

[Sleeper]

Hey, Ferrari was at the top of the sheets today, so now it is certain that they will win the championship ;) :D

What surprises me more is that they got in over 100 laps each, so far this winter we've normally been waiting for them to get into double figures. :p