The ABS discussion thread

[varunsangal]

Technologies like ABS, GPS are making for a better driving experience. Also, why forget the air con or even the radio? I remember anybody buying M800 DX was looked at with envy and the typical comment was "He has too much money." So, automotive technology has been fairly useful.

However, the latest driver-less cars have me a bit concerned given that the machine will be as capable as the person who programmed the machine. So there may be some way to go before we have mass produced (read Alto volumes) driver-less cars. Also, the roads in India need to be better. imagine a driver-less car swerving to avoid a pothole or an incorrectly parked rickshaw.

Also, my ultimate fear remains. In some sci-fi world, machines may decide that humans are incapable of driving, and there goes the entire fun.

Originally Posted by MaheshY1

No matter what the condition, snow, gravel, mud, or sand, ABS will always bring the car back to a stop faster and more importantly, in a straight line.

I have owned ABS cars for ~9 years now. So possibly a qualified comment here.

The primary thing that ABS does is to prevent the brakes from locking up in 'skid-prone' conditions and allows you to retain control of the car. The way this is done is by the ABS system locking and releasing the brakes multiple times a second. This increases the stopping distance by a small margin when compared to a similar distance on normal roads. The distance to stop warning is quoted in the owners manual as well, happy to post it here when I lay my hands on it next.

[motorhead16]

The difference in stopping distance with and without ABS is negligible considering how ABS with EBD ensures that you dont spin out of control under sudden braking. Also who cares if technology does x,y or z to a driver, we have about ten to fifteen years(maybe even less) before driver-less cars are made mandatory. Just blindly accusing technology does not make sense.

[varunsangal]

Originally Posted by MaheshY1

...No matter what the condition, snow, gravel, mud, or sand, ABS will always bring the car back to a stop faster and more importantly, in a straight line.

Originally Posted by varunsangal

...The distance to stop warning is quoted in the owners manual as well, happy to post it here when I lay my hands on it next.

Found a copy of the manual online. See the highlighted portions below.

[Thad E Ginathom]

Originally Posted by MaheshY1

That can't be true. Friction stops cars. Skidding on snow with wheels locked means lesser friction.

No matter what the condition, snow, gravel, mud, or sand, ABS will always bring the car back to a stop faster and more importantly, in a straight line.

Shoot me if I'm wrong. ...

Pass the gun!

No, seriously, I don't want to shoot anybody over this

But it is a never-ending circle of argument. It is not helped by those whose egos believe that they can control a car better than ABS can. But, as has been said, whilst ABS will do a fantastically better job than most drivers, on most surfaces, most of the time, occasionally it won't.

But the great thing about ABS is that it gives a driver some control over the car during the emergency stop.

If it is only necessary to stop in a straight line, there is less advantage to ABS. But, while screaching and skidding to that stop, leaving black rubber on the road, you can spin the steering wheel like a top and nothing will happen. And if that means hitting the thing in front of you, you will hot the thing in front of you. ABS gives some chance of steering.

As for those who insist they can do better than ABS, if they can show me their track, rally and skid-rink experience, I'll take them seriously.

EDIT: You are right in that ABS tries, by preventing wheel lock, to maximise the friction and braking efficiency.

[MaheshY1]

Originally Posted by varunsangal

Found a copy of the manual online. See the highlighted portions below.

Kudos. Keyword here is 'may'. Good luck with acquiring the skills to beat ABS.

Originally Posted by Thad E Ginathom

But the great thing about ABS is that it gives a driver some control over the car during the emergency stop.

Exactly my point. When a human does manage to beat the ABS in stopping distance, (s)he is going to wish (s)he had the car in control.

I'm not leaving it to chance. May God bless all with ABS.

[varunsangal]

Originally Posted by MaheshY1

Kudos. Keyword here is 'may'. Good luck with acquiring the skills to beat ABS.



Exactly my point. When a human does manage to beat the ABS in stopping distance, (s)he is going to wish (s)he had the car in control.

I'm not leaving it to chance. May God bless all with ABS.

I am with you on the need to have ABS, and not trying to beat ABS here. ABS is an essential feature, have owned one for the last 9 years, back in the day when ABS was a rarity in India.

The key point is the behavior of an ABS enabled car is different, and that the ultimate safely of the car and its occupants lies with the driver, who needs to understand the machine and the road.

[McLaren Rulez]

Originally Posted by MaheshY1

That can't be true. Friction stops cars. Skidding on snow with wheels locked means lesser friction.

No matter what the condition, snow, gravel, mud, or sand, ABS will always bring the car back to a stop faster and more importantly, in a straight line.

Shoot me if I'm wrong.

It is true that the maximum deceleration you can get is just before the wheels lock up. However, ABS systems must be calibrated to detect this lock up point. A badly calibrated system can indeed be beaten but this is rare. So technically, even on a paved road, a good driver can do better - but realistically, it simply isn't going to happen.

In snow and sand, a locked wheel digs in and this helps slow down much faster albeit without steering control.

[Rahul Rao]

Originally Posted by MaheshY1

No matter what the condition, snow, gravel, mud, or sand, ABS will always bring the car back to a stop faster and more importantly, in a straight line.

In a straight line I agree, you can steer while turning I agree too, but after driving same cars without and with ABS, I'm sure that a experienced driver can stop a car much faster without ABS. I currently have 3 cars of which one has ABS.
As I have driven 1.9 Lakh km in 2005 Innova without ABS and 1.64 lakh km in 2008 Innova with ABS, the ABS vehicle had noticably longer braking distance.
Same is case with my current Polo without ABS, and any other Polo with ABS.

Rahul

[Aroy]

ABS gives you consistent braking; even though longer distances; at all times. With no ABS the trajectory and braking distance depend wholly and solely on the driver skills.

So in an emergency situation for an average driver ABS is a boon, as long as they are cognizant of its limitation. Yes a very skilled driver can beat ABS performance in all cases, but then these drivers are limited to skilled professionals and a handful of amateurs.

There will always be some one with lightning fast reflexes who can better the BS and Auto Shifts, but not the average joe.

[Turbohead]

Originally Posted by Aroy

ABS gives you consistent braking; even though longer distances; at all times. With no ABS the trajectory and braking distance depend wholly and solely on the driver skills.

So in an emergency situation for an average driver ABS is a boon, as long as they are cognizant of its limitation. Yes a very skilled driver can beat ABS performance in all cases, but then these drivers are limited to skilled professionals and a handful of amateurs.

There will always be some one with lightning fast reflexes who can better the BS and Auto Shifts, but not the average joe.

So is it possible to reduce the braking distance in an ABS car without switching off the ABS? Or should we rely on 'threshold' braking?

[McLaren Rulez]

Originally Posted by Turbohead

So is it possible to reduce the braking distance in an ABS car without switching off the ABS? Or should we rely on 'threshold' braking?

Yes, it is possible to do so if your applied brake pressure is just below the lock up point. ABS will not activate in this case and this is probably what you meant by threshold braking.

However, finding that precise amount of braking pressure is incredibly hard. Look at this way - F1 drivers try to do exactly this on the same piece of track after at least a hundred laps of practice. And they still get it wrong and lock up now and then. What are the odds that a driver can do it on an unknown road in arbitrary conditions with differing amounts of weight (i.e. passengers and fuel) in what is likely a panic situation?

If you are on a racetrack though, it is certainly worth disabling your ABS to see if you are able to do better because you can find and memorize the threshold braking point.

[studentonwheels]

As per my experience driving in snow, your stopping distance is MUCH more with ABS than without. That is because while I was driving at about 25mph(40Kmph), I'd hit the brakes and feel the ABS clamping and releasing the wheels and that definitely increased my stopping distance compared to the time I drove on snow in a car with a disfunctional ABS. However, If I tried to corner a bit too fast in snow, EBD and traction control would come to my rescue and prevent me from understeer, and ABS definitely kept me on track more than once. And I've seen newer cars equipped with ABS doing a 90 or a 180 because the drivers didn't know how to drive on snow. So yes, ABS helps, but only if you know what you are doing.