Traction Control Issue
#21
ESC & TC are designed for "normal" driving, and I don't think track days meet the definition of normal.
From the TC programmer's stand point, wheelspin above a given threshold needs to be curtailed, and that's done by reducing power. The re-application of power is a bit more difficult. 100% cut in will make the car lurch and lose traction again, probably worsening the situation. Therefore, power is re-applied slowly, and you get rear ended by the lunatic Prius driver. Throttle control = no wheel spin = no fun.
ESC uses braking forces on individual wheels to counteract the spinning of the car. Accelerating individual wheels (torque vectoring) could accomplish the same thing, but it's politically incorrect. ESC is illegal in formula 1, and even the best drivers in the world are prohibited from controlling individual wheels. McLaren tried it, and got banned. You may have the skills to control a spin, but none of us get to control each wheel.
From the TC programmer's stand point, wheelspin above a given threshold needs to be curtailed, and that's done by reducing power. The re-application of power is a bit more difficult. 100% cut in will make the car lurch and lose traction again, probably worsening the situation. Therefore, power is re-applied slowly, and you get rear ended by the lunatic Prius driver. Throttle control = no wheel spin = no fun.
ESC uses braking forces on individual wheels to counteract the spinning of the car. Accelerating individual wheels (torque vectoring) could accomplish the same thing, but it's politically incorrect. ESC is illegal in formula 1, and even the best drivers in the world are prohibited from controlling individual wheels. McLaren tried it, and got banned. You may have the skills to control a spin, but none of us get to control each wheel.
#22
For those whose driving has only been the easy mild-mannered stuff of perhaps 4-cylinder-automatic Camry stereotype, I agree. They've never have intentionally experienced the feeling of one end of the car or other about to do something unintended, let alone had any experience taking the appropriate corrective action. With or without ESC.
As an individual's "regular street driving" ramps up in intensity at least occasionally, some awareness of what happens out past where tire behavior remains linear can be expected to take place. I'm going to make the stipulation that the driver is paying conscious attention to what the tires are doing under such conditions as well as to the usual conditions of normal street driving, otherwise he's just being a reckless accident waiting for a time and place to happen.
No, hard normal street driving doesn't directly translate to being prepared for aggressive track driving. But you wouldn't be trying to operate quite so far out of your element/comfort zone as the above "Camry stereotype" driver either. It's a much smaller step from reasonably frequent 0.5 lat-g experience in the dry up to 0.9 than from 0.2 to 0.9. Or from 0.3 to 0.6 vs from 0.1 to 0.6 in the wet.
At least when I'm driving on public roads, I don't think I've ever has ESC kick on on me, just maybe TC a few times and that's it. People don't usually drive to the point that they're riding on the edge of ESC and relying on it on a regular basis.
So it has to be set somewhat "conservatively", and all it can do then is presume that you're just another moron who's got himself in over his head, and act accordingly. Never mind what you may know as experience-based fact is comfortably do-able.
Agreed, relying on ESC and what-not on a regular basis is worse than stupid. Such people are actively teaching themselves to get away with doing all sorts of things that they shouldn't be doing or even be able to. Save that sort of "driving" for GT5.
I've personally never read about or heard about an accident being caused by ESC, i.e. "Person A was traveling on Y road, reacted to a situation, ESC kicked on and caused the person to crash and die" On the other hand, I've seen plenty of stories where "Person B was traveling on X road, reacted to a situation, lost control of the vehicle and died"
That was probably a relatively rare set of circumstances, but that it has already happened means that it certainly can and probably will again. Some folks will react to the secondary situation better and more successfully than others.
It's kind of relevant that the latest issue of Hot Rod magazine has a pretty good feature article that discusses Matt Jones' experience in retrofitting ESC to a restomod/pro-touring car (Matt is the mechanical engineer at Art Morrison, and evidently has a few industry connections). My point here is that he disconnects the lateral g sensor for track days. Otherwise it locks him down to a maximum of about 0.9 lat-g - and he's using a lot of Corvette components. Apparently nobody was willing to talk about raising ESC thresholds via reflash, even though Toyota almost certainly lowered them as part of the ESC recalibration in the Lexus GX460 SUV matter (http://www.autoweek.com/article/2010...NEWS/100419847).
BTW, I am truly sorry to hear how your experience went down. I know what you're saying about inexperience vs complacency. Kind of the difference between not knowing what can happen and not believing that it can happen to you. One falls into the latter category when one ignores what the car is trying to tell you from time to time.
Norm
Last edited by Norm Peterson; 06-13-2011 at 11:49 AM.
#23
Ever wonder why my sig says "1993 Cobra R.I.P"? Was driving an empty country road at high speed, armadillo walked out, instictively I tapped the brakes enough for the rears to lock up. Back end started to swing around, I let off but I couldn't recover. Went into a ditch and rolled 3 times into a wheat field. I'm lucky I didn't get severely injured...or dead. Since then I've been a much more careful driver and I know now to just hit a small animal than to try to avoid it. I had always thought I was a decent enough driver, and I thought I was being relatively safe. They say for pilots, the most dangerous ones are those with less than 1,000 hrs, and those with over 4,000 hrs. Complacency can be just as dangerous and inexperience. It can happen to anybody.
Anyway, I digress. Yes, I agree. I will never swerve to avoid a small animal. If I can safely avoid hitting such varmints, I will. But if I cannot do so safely, I will hit it instead and pay for whatever small damages it might cause.
Just like what Norm said, all that nanny crap cannot override the laws of physics. I know that no matter how much TC is played up, I cannot swerve to avoid an animal and rely on that crap to always save me (though for lesser situations, TC can actually help).
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