Anti-lock Braking System

How many of us have gone to a showroom to purchase a car, and found yourself in the midst of questions like, what the hell is ABS? I know what ABS stands for, but is it worth the extra mark-up? Does it really add to the safety of the drive? Under what conditions does it work? Is it a must?
Read on...

To begin with, ABS stands for Anti-lock Braking System.
Before I begin talking about what ABS is all about I will need to take you through an understanding of what do you mean by locking.

An ideal scenario is when you are traveling at a moderate speed, decide to brake, apply the pressure on your brake pedal and your car gradually comes to a halt. There are no worries here.

Now assume you are cruising at high speed and need to apply brakes very quickly! You press the brake pedal really hard!

What happens is that when you try to stop your car at a rate faster than that is allowed by the momentum of the vehicle, the wheels stop rotating due to the application of the brakes (the wheels LOCK) but the vehicle still continues to move forward due to the momentum and causes what is known as skidding.
The friction between the wheels and the road is not sufficient to stop the vehicle.
This is when the driver has minimum control over the vehicle.
This may happen when the initial speed is very high or the road is slippery.

What ABS does, is prevent the wheels from locking, thus keeping the vehicle under the control of the driver.

The big question now is, how does ABS manage that?

ABS has a set of speed sensors. What these speed sensors do is monitor the speed of the wheel and thus recognize when the wheel is close to getting locked on the application of the brakes.

The controller of the ABS system uses the information collected by the speed sensors to control the braking.

What the controller does is, when it recognizes that the wheel is about to lock, it releases the pressure on the wheel so as to free it. Once the wheel is free it gains speed. This is when the controller applies the pressure on the wheel so as to slow it down, again on until the point that it does not lock.

It repeats this exercise at a very high frequency (over 10 times a second) and thus provides the most efficient braking without locking!

As the wheels do not lock, you are able to steer while you brake in case required.
This does not mean that ABS guarantee safety against all the speed and braking related accidents. ABS can only assist you in preventing a skid and in case you need to steer your vehicle while braking, it will help you achieve it smoothly.

If you are in an unreasonable speed - braking situation no system can guarantee safety.

In India, ABS is usually an optional feature and that too in the top end models whereas abroad it is almost a standard. That is expected to be the scenario a few years down the line in India too.

So safety equipment does help, but doesn't take any responsibility away from the driver towards the safety of his passengers and other vehicles on the road.

Hope this was an informative read.