Friday, January 20, 2012

Lotus and the anti-dive system

Much has been recently written about the alleged system Lotus-Renault will use in its 2012 competitor.

The system is aimed to be of anti-dive type, thus help maintaining standard ride height during braking, while the usual movement would be to plunge onward and down.

Here's a technical diagram: 

Image courtesy of Omnicorse, original here.

At the same time Ferrari have reported that they are working on the same type of system, but they are 
awaiting final approval from the FIA over its legality.

Reportedly, FIA said OK to such system, as it has been found legal according to the rules, so lots of noise has been created about how the rest of the grid will have to copy that setup.

Red Bull, in the mean time, say that "there's no reason to rush and copy", as 
"Things have to work as a package rather than as individual components."
It has been reported that in the past Red Bull have tried similar approach, but it has been abandoned, perhaps in favor of working more deeply and actually developing the winning EBD concept, as I've described (translated) here.

On the other hand, the news on the Red Bull front have been virtually equal to zero, so I would assume they are quite busy at this time, which might explain why the unveiling of the car will be done online.

Let's rewind on the anti-dive systems, that's hardly the first time we hear about it. 
  • Back in the 70's we had Lotus 72, which had very advanced suspension geometry, including such anti-dive system. 
  • Then we have Honda's TRAC system, seen in the CB900F model, which was again back in the time, namely the 80's. 
So, those examples are here just to illustrate that such system isn't new to the world. Now, back in F1 and if you prefer the visual style, here's a video explanation.
Note: Personally I see a bit of contradiction with : 

10.2.3 No adjustment may be made to the suspension system while the car is in motion. 
But honestly, I don't know what's really going to happen.

Some speculate that such setup could be a real gainer, with selective quotes up to 0.5 seconds per lap, but personally I would disagree. Such ride height control systems are present in the cars to some extent, depending on the car setup and overall philosophy, and I don't find it such a great gizmo that can greatly boost the performance of any team.

I'd rather call it an "aid" to a properly thought of and crafted car, as the suspension travel is very small, thus the gain would be max if one can utilize the effect of the travel along with the rest of the setup of the car.
This means that such system will have effect if the front end of the car is designed carefully around it, as well as the rest of the package.

There's a pretty good advantage, however, on the fuel load side, as the cars start with about 150 kg of fuel, and lighten up throughout the race. The inference is up to you.

Certainly, what's really going to happen, we're about to see.

UPDATE: 28.09.2012 - James Allison told PMWM about the system: "It was complicated. “Done wrong, you could get quite a nasty brake judder with this bouncing caliper. Engineering it so the car moves up exactly the amount that it would otherwise have dipped down by – that’s all quite beautiful when you get it right. We were rather proud of having done it and were looking forward to using it.”

Wednesday, January 4, 2012

RB7 - The Red Bull F1 Racing Car and its core success values

The following text is a best effort translation - the original source is located here- the article is in Bulgarian, its author is Ivan Tenchev - Editor in Chief at ClubS1 Magazine. I have his explicit written permission to link it here, which I'm thankful for.

The aim of that translated article is simple - to get this excellent content reaching more people, interested just as me in the huge success of RB7 - The Red Bull F1 Racing Car and overall in technical stuff related to F1.

Going back into 2011, it's quite obvious that the advantage RB7 had was more than phenomenal. We witnessed light-speed-like qualification laps and race pace which was often unreachable even for the top teams like Ferrari and Mclaren.
So, what really lies underneath that rocket ship? Let's go down into the details.

Even from a basic view it's very evident that the car has its roots related to the predecessors - RB5 from 2009 and RB6 from 2010 - they are all from the same breed.
When FIA ratified the most radical rule change since the beginning of 80's Adrian Newey saw an excellent opportunity to create brand new concept of a car, and including many forgotten elements.

  • Rear suspension of pull-rod type was introduced - the main driver for that choice was, as the constructor himself explained, that many elements are getting more and more closer to the floor, thus overall lowering the center of gravity, and as a subsequent benefit making the rear more tightly packaged. This allows the bottom element of the rear wing to be lower, thus improving downforce without loosing the straight line speed. 
  • At the same time a high-profile nose was selected along with a front wing situated as close as possible to the ground, whose sides were rather high, aiming to direct the air outside, around the front wheels, and not to do complex modeling towards the floor of the car.
    The reason for that change was allowed by the rules and discovered by Newey - the width of the front wing became 1800mm from 1400 providing that the overall car width was 2000mm.
  • The next choice was the selection of Renault engines - not as powerful as the others, however requiring less cooling and being very flexible at the same time. 
Newey was already working on old-known concept - the infamous diffuser blowing with gases passing through the motor and creating constant downforce stream on the rear end.

It's also curious to mention that all of Newey's ideas are first drafted on the old-fashion drawing board, and then the schema goes through the CAD -> CFD - Aero-tunnel cycle.
Author's note: I mean this:

The 2009 project was really strong and it's worth mentioning that the key role was played by the single diffuser. Recently Newey revealed that he wouldn't have gone into pull-rod suspension, if he knew that FIA would allow the double diffusers of Brawn, Williams and Toyota:
Newey: For a single diffuser the pull-rod is very elegant solution, but the height of the double diffuser per se will create many problems.
However, given that fact that the Double Diffuser turned out to be a key element in 2009, Newey had to open the rear part of the floor and, surprisingly, in Monaco 2009 the car was with double diffuser and later was able to surpass his opponent, Brawn - a car made specifically with double diffusers in mind.

Then, in 2010 RB6 was already built around the double diffusers, the car was very fast, but there were problems, too. Most of the ideas from 2009 had to be combined with the new changes, amongst which was the bigger fuel tank - a consequence of the refueling ban. That led to a compromise with radiators' size, which were to bound with the overall idea of the construction.
The aerodynamic was still very good, the additionally lifted rear part was much more flexible to play with when blowing the double diffusers with exhaust gases.

Having the front wing very close to the ground, along with the overall rake of the car onward, was assuring very clear stream underneath the car. There was playing and fine tuning with the balance and the weight of the details, in order to optimize the work of the tires and the brakes.

For 2011 the double diffusers were banned, and a mandatory weight distribution was introduced, namely: 291 kg on the front and 342 kg on the rear axis. Hence, having in mind the minimum weight of 640 kg, Newey had only 7 kg to play with, but he made that move brilliantly, by putting them in the front part.
That way the car was able to heat the front Pirelli tires up to optimal temperature faster than anyone else.
Basically the front tires are more problematic in getting up to temperature, and even that could explain the excellent performance of Red Bull in the qualification sessions.

It was also evident, however, that RB7 was beginning to wear out the tires in the high-speed turns faster than the rivals like Mclaren and especially Ferrari. But on the other hand, such corners are not present on most of the F1 tracks. The bottom line was that Red Bull was having issues on classic tracks like Silverstone and Germany, so they decided to sacrifice them in favor of the newly introduced tracks.

On the rear of the car a single, optimized diffuser was used, which was very close to the whole concept of RB5, which was actually an advantage from a structural and aerodynamic point of view.

RB5 was created to work with KERS, too, but in Red Bull quickly dismissed the system after the first tests in 2009. For 2011, however, the use of the system became mandatory and that turned out to be the biggest problem of the team, because unlike the others, they had no prior racing experience with it. At the same time they were trying to further improve the system, separately from Renault, whose development they were using as a base package.

Having aerodynamics as a main priority, Newey selected some unorthodox solutions for the system. First he put the batteries and the electronic control block on both sides of the car under the radiators. All other competitors, considering the experience from 2009, put all those units in the middle, under the fuel tank.
At the same time, concerned about the large size of the fuel tank, and in order not to break the overall balance, Newey decided to use smaller lithium ion batteries, which would require less energy for cooling purposes. This way he avoided the need of larger radiators for KERS cooling.
The smaller batteries, however, produced smaller power output, equal to about 60 HP, as opposed to the 80 HP for the rest of the grid.
It's also worth considering the fact that the system itself was fragile in terms of reliability, thus rendering it unusable, which might explain the smaller time differences in the races, compared to the rivals.

Having extra bag of useful knowledge, Newey and his team had a solution for those issues. The setup of the car was modified to be very fast in one lap and thus getting P1. Then, with a good pace for a couple of laps (while others were still heating up the tires) they had more than 1 second advantage, hence being invulnerable to the rival's DRS system and then keeping up to speed.

In order to achieve that behavior, the setup of the aerodynamics itself was very important. The car was primarily setup to be fast in the bends, with a trade-off for lower speed on the straights.
In Germany, for instance, Mark Webber still managed to snatch the pole position, regardless of the fact that RBR were 5 km/h slower than Renault on the straights.

In the race, however, the leadership was inevitably lost. The telemetry data analyzed by the other teams showed the great advantage that Red Bull had in the bends - they were able to use second and third gear!
There was a new transmission available from the Milton Keynes team - although in general it was the same as in 2009 and 2010, it had a new housing and different gear ratios, in accordance with the current setup and KERS and everything else meaningful.
That particular choice of gear ratios can talk a lot about the team and its dedicated work in regards to mechanics and dynamics as a factors, forming the overall package.

Undoubtedly, Newey is genuinely talented in aerodynamics - but as he mentions himself, he has graduated in aeronautics, too.
It's also true that since the late 70's the aerodynamics is a leading part of Formula 1, but at the same time his team put a lot of attention to the mechanics (transmission as an evidence), as well as the safety.

In the recent seasons a laser system by Leica was introduced in Milton Keynes. It checks each one of the details produced and RB7 became the most safe and reliable car in 2011, which managed to complete all of the 1362 laps possible in the first 11 races. Besides, both drivers have scored points in every race.

So, yes, Williams FW14B and Mclaren MP4-4 were truly amazing capable pieces of machinery, but RB7 is also very special, even though not having all of their huge superiority.

Thanks for reading all the way down - I'll be glad to share more and more insights from Ivan Tenchev and ClubS1 Magazine.
You can follow their account at Twitter - @ClubS1Magazine