October 3, 2013

So How is Red Bull running traction control legally?

You might have noticed a number of articles here and there trying to rationalize Vettel's crushing advantage in Singapore.   The guy is quick but 2 seconds a lap quicker the everyone else, based on talent alone, nobody's buying that one.  The secret is in the car,  or rather the car and driver package.

One theory revolves around engine mapping.  As you know, F1 cars used to get huge downforce by "blowing" the diffuser on the off throttle,  having fuel mix combust in the headers rather than on top of the pistons and thus keeping the exhaust flow energized.   This was banned after 2011.

In 2012 it became clear that where you come up with a rule, designers will figure a way around it.  So Coanda effect exhausts and even more work on engine mapping  made engines honk much like when they were "blowing" , which of course, they cannot anymore.



That first car by in the clip, published by Autosprint, is Vettel in Singapore.  One thing is certain, his RB9 is the only car making that distinctive sound.  Webber's RB9, the fourth car in the clip, sounds "normal".
But is that really the secret, it's still pushing exhaust pressure on the off throttle?  I'd say no way Red Bull would try to get away with something that blatant.  What you are hearing are cylinders being shut off, something Mr Whiting gave a pass to Renault last year as long as it's no more than 4 at a time (Renault pleaded reliability).  Red Bull's software has been checked and re-checked by the FIA because other teams have raised the issue  so, if they are "blowing", they are doing it by "cheating" legally, so to speak.

The biggest advantage for the RB9 is slow corner traction, Singapore is the most extreme example of a point and squirt track. Montreal is also a point and squirt track and, if you remember, there was more than a few questions about traction control there as well,  along with the same honky engine sounds being heard at times.

Of course if the "buzz" were traction control, it would not happen mid corner but on corner exit,
so, how might a form of traction control, or perhaps, Torque Control work?    All manner of theories have been bouncing around online,  one has been given a big boost in credibility by an article in Racecar Engineering:  the use of KERS charging to modulate power.

KERS has a defined amount of power it can store and discharge but there is no obligation on when to charge it so, the theory goes that Red Bull has figured out a way to use the charging phase to modulate output torque on corner exit.  If this were controlled in response to wheelspin,  it would be traction control and illegal.  What Racecar Engineering is speculating is that it is controlled by sensors in the shocks: shock is compressed means more grip then you have full power, shock is extended then you might get less torque (because it's charging KERS) and less potential wheelspin.    In effect a form of traction control which seems to be legal by the letter of the rules.  Remember Webber's tire marks in Montreal?

You might imagine  a system like this would require extra sensors and controllers While the KERS system is separate from the auxiliary electrical system, it is also known that the RB9 places especially high demands on its alternators which led to failures in the past (as constructed, materials were not up to demands).   A connection?

There are of course a bunch of other theories out there about what Newey might have come up with, these are more in the "there was no moon landing" category but, for fun...

- there are electrical heating elements placed behind the diffuser "intake" holes which, using battery power, superheat the airflow providing the same effect as exhaust blowing.
-Red Bull is able to "package" the rear of the car so tightly because they are using a "Peltier effect" heat pump to cool the exhaust.

As I said, sci-fi, but fun.

What is going on is Red Bull have come up with something that works, but works perfectly because Vettel knows how to take full advantage of it.  The car is build around him, what he's good at and what he knows how to fully exploit.   Webber may very well have precisely the same car but he, for whatever reason, is not able to extract that same advantage consistently.

Optimizing the package and pushing the rules,  that's what F1 is all about, love it or hate it.



24 comments:

  1. The speeds at the apex of the corners are nearly identical, but from apex out the RedBull is 5-10 km/h faster.

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  2. These stories always make my engineering bits all fizzy.
    My moon landing theory is that they are using nonlinear fluid dynamics (think F-duct) in the fuel lines to set up pressure oscillations and modulate the engine with what is effectively an auxiliary analogue ECU.
    At least this is the kind of crazy thing I would love to hear.

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  3. The KERS harvesting theory does have some interesting implications, and it would fit in very well with reliability issues and failures this season of the RB9 - specifically Webber's regular issues with KERS (Vettle as well but not as much as Webber, if I recall). It's been overheard more than a few times that KERS has hampered Webber in one way or another.


    If you think about it, it makes perfect sense - Webber's chassis has been used to develop the system during the actual races, providing Vettel with more reliable components down the road, keeping him so far ahead of the rest of the field. As with the 'bendy nose' and flaxible floor structure and all the rest of the 'grey' stuff RBR has been known to employ, there's no reason why they'd bolt the new, trick components on the lead car until they've been sorted out.


    Also, keep in mind the many, many poor starts Webber has had over the last two seasons. Unless his skill has degraded as he's gained more experience on-track, all the sign point to some sort of issue with the car setup. If this harvesting/traction control system is indeed the reason for Vettel's disgusting dominance (seriously, many people watching the last race were utterly turned off by this display - such a huge performance margin, especially between the 'same' cars, would lead any objective observer to question just wtf is going on here) it only stands to reason that webber has been the test mule and has suffered because of it.


    At this point it's starting to look like the only real racing is going on midfield, and F1 fans are turning away in droves. Some pundits blamed Pirelli earlier this year, but look what's happened since the tire issue has been sorted out a bit. Given that the tires are the only thing RBR cannot actually control, it stands to reason that 'crappy' tires may be the only way to keep Vettel from almost literally walking away with the title again this year.


    It's getting old.

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  4. Don't forget, Red Bull was crap on the original 2013 Pirellis then they squeaked enough to get the grease...

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  5. Your sir, have just blown my mind. Nothing remotely close to a thought like that has ever crossed my mind as being a possible solution. What are the regs on fuel pump control? Or would they be doing so passively with the plumbing itself?

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  6. I was at Spa and they were using the system, it was so obvious something odd was going on we were all wondering how they were getting away with it. I didn't see the last race were any of the teams openly complaining or is it all done by non-attributed comments to the press?


    If they aren't openly complaining i'd think all the other teams want to use it next year.

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  7. Kinda smells weird in here.

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  8. the problem with that theory is that you'd end up starving the engine under load. A lean condition would quickly cause other problems and negate any of the other ecu tweaking tricks. Given the high rpms and ignition/valve adjustments these engines are capable of an 'analog' system would be far too slow to provide enough response to make much of a difference.

    If we were talking about something less than about 10k rpms for peak power and torque, I could maybe see where this could be possible. I don't think they'd risk a blown engine due to lean conditions though.

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  9. I haven't a clue about regulations or whether the injector technology would allow pressure variations to propagate through them. (E.g. positive displacement pumps in the injectors would negate any line pressure effects.)

    I do know that you can construct passive fluidic amplifiers, oscillators, and equivalent LRC circuit elements. If you want to go digital, you can construct Turing-complete logic gates. All this as long as you have a high pressure reservoir and appropriately constructed pipes.

    Digital fluidic logic just would not scale to the demands of a traction control system. I would think that if this were actually used in engine control, it would be in the form of analogue fuel pressure amplifiers and oscillators, with feedback and control coming from both the flow rate and the use of fluid mass as an accelerometer.

    That being said, I still believe this is more sci-fi at this point and it's more likely that KERS charging is the mechanism in use by RBR.

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  10. Ah. Open throttle and restricted fuel results in more widespread effects than just reduced power, I guess.

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  11. The whoopie-cushion like sound makes me wonder if they are squeezing exhaust between bits of carbon fibre bodywork? Perhaps something flexes under lateral g-loading and allows the diffuser to be blown but only under those dynamic conditions?

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  12. British F1 fans always tend to be jealous of German F1 driver's success....this has been going on for nearly 2 decades ever since 1994. How many English drivers could speak a smidgen of German? It's obvious that Vettel & Schumacher before him, sometimes incorrectly phrase their English sentences.

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  13. I wonder if the KERS can be charged outside of just braking.

    If that is the case, they could effectively use the KERS under acceleration with some trickery with the programming/logic and sensors on the wheel speed/engine-transmission torque areas. This could put more load on the engine temporarily but could be engaged instantaneously.

    I know they've had more conversation over the radio about KERS settings than any of the other teams. I feel that the source of their "TCS" if you could call it that is centered in the KERS control logic.

    If it is picking up wheel spin or suspension issues in bumpy sections, it could sense that through the sensors/telemetry and kick the kers in at that special moment to keep the car happy upon exit.

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  14. You'd want to be careful about what you infer from radio messages, only because we only get to hear just fragments...

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  15. All team comms are, by mandate, fully available to the public and the British broadcasters also have a feature that allows fans to follow each team and their comms under that 'red button' (or so I'm led to believe by the torrents I watch).


    Obv they're interested in keeping data close, as we see via Alonso and his italian comms, but it's not a stretch to think that the combined comms do indicate RBR has KERS issues. they've also publicly admitted to multiple KERS failures and issues that hampered their overall performance, most notably in webber's chassis.

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  16. Seems like you know quite a bit more than my basic knowledge of the topic allows for, and you still land on the 'yeah right' side over 'could be'.


    As I am pretty well versed in the harvesting and modulation of the KERS systems (albeit through very different circumstances) the more I look into this theory the more likely it is that RBR has found a way to use the harvesting as a means of modulating the torque that gets to the wheels. What I don't know, and have been unable to find out, is if there is any restriction to the harvesting during on-throttle or non-braking events. Obviously they wouldn't have thought to restrict that capacity as the manner of power delivery in F1 would generally discourage anything less than full-power during WOT or even partial throttle.


    I've been tsk-tsk'ed at some other forums for suggesting that Webber's chassis has been used as a race-stress test platform but obviously RBR has little concern about their overall standing given the dominance we've seen since the tire situation was dealt with.


    And now, I see that smug mug taking poll this weekend, and webber in 3rd. Perhaps they decided to dial it back a bit and keep their secret for next season, what with all the new doo-dads and tech/energy harvesting stuff. Makes me sad to think we may be looking at 5 on the run without any actual challenge to either the constructors or drivers' title. BOOOO!

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  17. There is no need to charge KERS outside of breaking, there isn't a track where they can't charge the battery fully on a lap. The only issues have been when the battery is fully charged, the car brakes differently without the drag of the charger.

    I don't know of any radiators using peltier devices to help cool the radiator fluid or the battery. That being said, I didn't see any restrictions on using the KERS battery power, except for 5.11: 'With the exception of any KERS or capacitor circuitry or coils being used solely to provide ignition, any device with a current requirement greater than 50mA or a power requirement greater than 1W may only be supplied at or below the primary regulated voltage.'
    If peltier devices were efficient to cool the car, you could restrict the radiator openings, thus reducing drag.

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  18. I would go for the simplest system - the electric engine in the KERS system has a rpm sensor on it's own. A simple procedure in the KERS management system would calculate the theoretical "perfect" increase of the crankshaft rpm ("perfect" as in "under ideal traction and minimum wheelspin") for each gear and engage the braking/charging procedure of the crankshaft speed changes too rapidly. As far as I know, the KERS management map is not due to FIA scrutiny (correct me if I am wrong) and this "traction control" does not use any additional parts, just software.

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  19. Agree w/ the viddy interesting assessment. This gives some plausibility to what I've suspected all along.

    My guess is that Webber does not have the same car, though. IMHO, the problems noted by gravit8ed, along w/ Webber's racing skills, make gravit8ed's 'experimental / development car' theory more likely. This also may help explain why Webber's bailing next yr.

    As for 'pushing the rules', I, for 1, hate it. It's on par w/ athletes who use(d) PED's because they either weren't tested or found ways to avoid detection.....

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  20. “9.3 Traction control
    No car may be equipped with a system or device which is capable of preventing the driven wheels from spinning under power or of compensating for excessive torque demand by the driver.
    Any device or system which notifies the driver of the onset of wheel spin is not permitted.”



    Any comments on the rule? Any "system or device" is not permitted. So how can the system be legal?

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  21. If the RB9 can be programmed to shut off cylinders, couldn't this alone be used gain traction or prevent wheelspin at certain points? IOW, it might be much easier for a driver to apply just the perfect amount of throttle with just 4 cylinders, where with all 8 it might be much trickier to get it right? Perfectly legal, too.

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  22. You would want to be cautious about what a person infer coming from radio communications, merely because most of us merely get to pick up merely fragments.

    Challenges for graphic designers

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  23. This blog is all about stupidity and hate. Just think about their gear ratios compared to mercedes. They are using short shifting. Thats one way to go faster on corner exits. And the way vettel is braking and flicking the steering wheel to reduce speed and pointing it out the corners. Watch him how he drive even though drivers just use this to reduce too much speed while they overtake at corners. Vettel always use this.

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