How Anti-Blockier System Works?


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350Z

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I saw this article in our forum posted by napster, So thought to share same with you all here as well.

The theory behind anti-lock brakes (ABS) is simple.

A skidding wheel (where the tire contact patch is sliding relative to the road)
has less traction than a non-skidding wheel. If you have been
stuck on ice, you know that if your wheels are spinning you have no traction.
This is because the contact patch is sliding relative to the ice. By keeping the wheels from skidding while you slow down, anti-lock brakes benefit you in two ways: You'll stop faster, and you'll be able to steer while you stop.

There are four main components to an ABS system:
  • Speed sensors
  • Pump
  • Valves
  • Controller
Speed Sensors

The anti-lock braking system
needs some way of knowing when a wheel is about to lock up. The speed sensors, which are located at each wheel, or in some cases in the differential, provide this information.

Valves
There is a valve in the brake line of
each brake controlled by the
ABS. On some systems, the valve has three positions:

In position one, the valve is open; pressure from the master cylinder is passed right through to the brake.
In position two, the valve blocks the line, isolating that
brake from the master cylinder. This prevents the pressure from rising further
should the driver push the brake pedal harder.
In position three, the valve releases some of the pressure
from the brake.

Pump
Since the valve is able to release pressure
from the brakes, there has to be some way to put that pressure back. That is what the pump does; when a valve reduces the pressure in a line, the pump is there to get the pressure back up.

Controller
The controller is a computer in the
car. It watches the speed sensors and controls the valves.
ABS at Work

There are many different variations and
control algorithms for ABS systems. We will discuss how one of the simpler
systems works.

The controller monitors the speed sensors at all times. It is looking for
decelerations in the wheel that are out of the ordinary. Right
before a wheel locks up, it will experience a rapid deceleration. If left
unchecked, the wheel would stop much more quickly than any car could. It mighttake a car five seconds to stop from 60 mph (96.6 kph) under ideal conditions,but a wheel that locks up could stop spinning in less than a second.

The ABS controller knows that such a rapid deceleration is impossible, so it reduces the pressure to that brake until it sees an
acceleration, then it increases the pressure until it sees the deceleration
again. It can do this very quickly, before the tire can actually significantly change speed. The
result is that the tire slows down at the same rate as the car, with the brakes keeping the tires very near the point at which they will start to lock up. This gives the system maximum braking power.

When the ABS system is in operation you will feel a pulsing
in the brake pedal; this comes from the rapid opening and closing of the valves. Some ABS systems can cycle up to 15 times per second.



Source: How Stuff Works via TAI Old Forum
 
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I think we should make safety a prime motto here at TAI advising all our members to go for safety options in the cars though its a bit costly.But as Zinam's signature says
'Safety isn't expensive its priceless.'
ABS is a compulsion for every car on the road!!
I myself regret not having ABS ob my car.
 
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I agree. ABS is must and thats why i choose Emotion variant for Punto.
One of my friend met with an accident, his car skidded in rain and hit another car.
 
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Yes Guys ABS is very important and really nice information 350Z appreciated[thumbsup] and as addy said ABS are a must in any car because our life is precious
 
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A nice info 350Z.

I think our cops too need to learn these things.

Reason , a month back my frens innova met an accident. the accident was terrible.

Police blame the driver as he slept. they found as there was no tyre mark , so he didn't brake and so on.

its a v innova.
 
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ilango[speed thirst];10533 said:
A nice info 350Z.

I think our cops too need to learn these things.

Reason , a month back my frens innova met an accident. the accident was terrible.

Police blame the driver as he slept. they found as there was no tyre mark , so he didn't brake and so on.

its a v innova.
That's a stupid blame. What if the car is slow enough to brake without locking or the driver modulated the brakes pretty well to stop without locking wheels? Any way on a accident, cars will be dragged after collision, then that would give tyre marks. Only braking at the final moment, will make the driver to jam the brakes, causing the wheels to lock, it is more evident when the driver sleeps for a second and wakes up to jam the brakes?
 
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When the ABS system is in operation you will feel a pulsing
in the brake pedal; this comes from the rapid opening and closing of the valves. Some ABS systems can cycle up to 15 times per second.
And here comes the problem. The problem in India is that when Drivers feel a pulsating Brake pedal, they remove the braking force, Telling that ABS is working, so i dont need to brake hard!![shock]
But the thing with abs is dat u can brake hard. without a fear. Dont know when people understand it. I;ve heard many accidents happening because of "ABS kam kar kar rha hai. I dont need to brake hard"[frustration]
 
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And here comes the problem. The problem in India is that when Drivers feel a pulsating Brake pedal, they remove the braking force, Telling that ABS is working, so i dont need to brake hard!![shock]
But the thing with abs is dat u can brake hard. without a fear. Dont know when people understand it. I;ve heard many accidents happening because of "ABS kam kar kar rha hai. I dont need to brake hard"[frustration]
This is the first time i am hearing something like this.Seriously ![shock]
I mean you gotta stop & your not braking hard thinking ABS will stop you car[lol]
 
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Okay!!

I have query!

Is it possible to install ABS in OEM Car ?

Has anyone done it ? How much does it cost ?
 
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Okay!!

I have query!

Is it possible to install ABS in OEM Car ?

Has anyone done it ? How much does it cost ?
Theroritically, it can be done, like abs from Swift Zxi in Swift Vxi, as the components will be same, but the workmanship plays a heavy role here, so i wont suggest anybody to go for such an aftermarket mod, that too on a system component as BRAKES[shock]
 
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Hmmm.. I felt bit bad, when i braked in these rains in chennai.

May be unsecure!

So just thought of checking with the guys here!

Even the Hyundai Guys are not recommending :(
 
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