Anti-Lock Brakes

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Actually, for dry pavement, maximum force occurs with just a small amount of sliding between the rubber and the road surface.
ABS may maximize braking force for drivers of ordinary skill, but it provides no such benefit to a highly skilled driver.
--
Alan Baker
Vancouver, British Columbia
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Alan Baker wrote:

In truth, though, few drivers fall into that category, and fewer yet can rely on that skill in an emergency.
Where ABS has fallen down, and where I've found it to be a hindrance, is in poor conditions where it will trade off braking power for stability (e.g. patchy ice or snow) although they have gotten quite a bit better over the years.
The sad thing though is that ABS has really not made us any safer...
nate
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Absolutely.
I know.
cf. "The law of unintended consequences".
:-(
--
Alan Baker
Vancouver, British Columbia
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The argument is made that even highly skilled people can panic in a crisis situation.
Personally, I don't think that is sufficiently good argument. Mind you, I have panicked plenty of times myself, but I'd still rather be in control than have automation be. --scott
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ABS and stability control can help the experienced driver keep control in some of the toughest conditions.
In the same car within minutes of each test I've tried maneuvers on a slippery surface both with and without ESC and it allows better control in turns. I made two passes with and two passes with out the control functioning. No comparison, the ESC was far superior. Automaton does not take control, it allows you to have control. All you have to do is try it and you'll be convinced.
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If one needs convincing of this, the most skillful drivers in the world are probably in F1...
...and they banned traction control and ABS because it was working to make the cars easier to drive even for them.
--
Alan Baker
Vancouver, British Columbia
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Alan Baker wrote:

Hooey. Their cars have been refined to the point that the skill of the driver matters a lot less now than in Mario Andretti's day. The failure of F1 drivers to succeed in other series in recent years backs this up. F1 still demands lightning reflexes which is why successful F1 drivers are always very young, but old-fashioned car control is less of an issue, IMO.

And its much harder to police just how traction control is being used to aid the driver.
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Ed Pawlowski wrote:

PolicySpy wrote:
I don't think that ABS is needed on dry pavement with the front wheels straight. I do think that ABS is needed on dry pavement with the wheels turned. And I think that ABS is needed very much in the rain...
But Electronic-Stability-Control ? Well...ESC essentially corrects for a slide by straightening up the vehicle with braking of individual wheels. The problem is that when correcting for a slide...the rear-end of the vehicle can be snapped by in line at the end of the curve. But at mid-curve the rear-end of the vehicle can't be snapped back in line...because a rear-end slide at mid-curve must be carried all the way to the end of the curve. Now...ESC was first developed to improve the slalom performcance of an S-Class Mercedes. But in a slalom the vehicle is instantly at the end of the curve and never really at mid-curve. So the question is...what does ESC do at mid-curve when the vehicle is going 50 MPH and the rear-end is stepped out 20 degrees ? If the ESC snaps the rear-end of the vehicle back into line...at mid-curve...at 50 MPH...that is a spin-out !
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Please don't continue.
--
Alan Baker
Vancouver, British Columbia
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It prevents you from getting into a bad situation in the first place
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PolicySpy wrote:

Pawlowski wrote:

PolicySpy:
That's very good viewpoint...and something to consider.
But mid-curve is a extreme and critical situation. And an overcorrection at mid-curve is catastrophic to vehicle stability...in that the vehicle twists around so that the nose of the vehicle is going off the outside of the road with the vehicle still under the G-force of being in the curve.
On the high bank race tracks...any slide is immediately an overcorrection...because of the magnification of the traction from the banking...because of high speed air on the side of the car...and now because of the traction of newly developed racing tires.
But recently any slide by a formula car is immediately an overcorrection...because of the traction of newly developed race tires.
But the average person on the street can overcorrect at mid-curve simply by correcting too soon or too much or too fast. At midcurve the rear-end of the car can't be snapped back in line but the slide must be carried to the end of the curve.
And if the car is trying to slide at mid-curve but the ESC is trying to prevent the slide...that is an overcorrection. At midcurve a slide must be allowed...and anything else is an over-correction.
A race car that slides at midcurve immediately hooks-up and that is a spin-out. Race car drivers prevent the hook-up by locking up the brakes of the vehicle in the curve...and the vehicle continues on an arc that will leave the track but avoids going off the track at a steep angle. Hopefully the race car driver just avoids the slide at midcurve and then runs out of track width (instead) at the exit of the corner.
Of course a street car can slide at midcurve without an immediate hook-up. But the action of the ESC at midcurve might be the hook-up...that launches the vehicle off the road at a steep angle.
A midcurve slide is just a much more extreme situation than a slide at the end of a curve...
In fact if you were going to practice 50-MPH 20-degree slides at a driving school...the practice and track set-up would represent an end-of-curve slide. A mid-curve slide would be too difficult to set-up because it would require holding racing level cornering loads through a long curve...
But a driver on the street can make a mistake and find themselves in a slide at midcurve...
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I don't have any evidence on the ESc under that particular condition either way. Do you?
You set up one scenario that may, or may not, be critical with ESC. Factor in the so many more scenarios where it can keep a car under control in slippery conditions, too fast on the exit ramp, avoidance maneuver to change lanes quickly, etc.
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wrote in message >

mismatched-under/over inflated -bald tires- People who think they have the skills of a Formula 1 drivers but don't (Been there, then I grew up)
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OR there's an underlying mechanical problem causing it to activate all the time, OR its a piss-poor ABS design (there are lots of them out there).
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The only one that bugged me was the ones on the 90's suburban, and they were mediocre at the best, but they worked. the worst ABS that I delt with were the "experimental" models that worked fine- but by the time they failed parts were rare and exorbitant. And I have NEVER, EVER had any model car come into a shop with any abs activate all the time. The closest would be a car that was over sensitive. I think in regards to ABS, people make Mountains from Molehills. As far as a car is concerned, that system has been one of the ones I have had to work the least on. Stephen H.
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S.Hansen wrote:

I can remember driving Dodge vans with and without ABS... this would have been mid 90's. It was dangerous because unless you remembered which van you were in you might "float" into the middle of an intersection. Bad weather plus ABS = no brakes in those vans.
fortunately, ABS has improved since then...
nate
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Just a few days ago was driving a buddies Dodge p/u (2000) a different vehicle has a different feel... Had to be real careful, my subie engine was in the back not strapped down!
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S.Hansen wrote:

True dat, but my point was that there were actually a couple vans, within a few model years of each other and essentially identical except one had ABS and the other didn't (probably a model year or two older.) The one without ABS was much easier to stop in poor weather, as if you activated the ABS it would get waaaaay to aggressive and you'd lose almost all braking, even if you just hit a short patch of ice that you would have hardly noticed in the non-ABS van.
nate
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S.Hansen wrote:

<snip>
You do realize that by "all the time" I didn't literally mean "all the time." ;-)
What I meant was that if you *routinely* feel ABS activating, (say several times a week) then something is probably wrong and causing the ABS to have to work in situations where the regular braking system should be able to cope just fine.
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Scott Dorsey wrote:

Exactly. But people have erroneously claimed several times in this thread that ABS *is* supposed to do this. Its not. The hydraulic/mechanical system should be set up for this already so that ABS doesn't have to deal with it. ABS is supposed to kick in when a) one or more wheels has significantly reduced traction compared to the others, or b) what you said:
>The ABS exists to

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