How Abs System Works In Cars?
Anti Lock Braking System: How It Works?
As I said in the last article, Anti Lock Braking System - Use of Abs in Cars, that in case of emergency, applying and releasing brakes continuously will reduce the stopping distance by a considerable margin as well as prevent the wheels from locking so you can steer the vehicle away from the object, but, the fact is, whatever I said, sounds so easy to do but so tough to actually perform. Think honestly, how many of you actually remember performing this in such a panic condition? Actually, no one and apart from this, even if you remember to do so, how fast actually you can perform the act of pressing and releasing of brakes? Not much, at least less than the required speed of doing so.
Here comes ABS in picture. Whatever action of pressing and releasing the brakes is concerned, it does it with accuracy and required speed without failure. It presses and releases the brakes almost 20 times a second, stopping the vehicle in a shorter time and distance. But how? How it knows that it has to do this? How it knows that the wheel has locked up? What is that which applies and releases brakes continuously when actually it’s only you who pressed the brake pedal? I will tell it all.
nti lock braking system is made up of a central (ECU) Electronic Control Unit and four wheel speed sensors connected to each wheel of vehicle and two hydraulic valves located in the brake hydraulics. The electronic control unit monitors the rotating speed of four wheels on a constant basis and when this system finds a vehicle wheel rotating speed slower than the other three, where a situation arises such as an impending wheel lock, here the ABS system causes the valves to constantly reduce hydraulic pressure to brakes of the significantly lowered speed wheel thereby causing reduction of braking force on the affected wheel.
By this process, the lower speed wheel starts turning faster than other three wheels and when the electronic control unit finds that the wheel is turning faster than the other three, automatically brake hydraulic pressure to the affected wheel is increased by the ABS system so that braking force is reapplied and the wheel slows down. This complete process performed by the ABS system is repeated continuously throughout the drive on mostly uneven roads and can be easily detected by the driver of the car with the help of brake pedal pulsation. A branded and good quality anti lock braking system can easily apply and then release the braking pressure on the wheels up to twenty times per second. This greatly reduces the braking distance which in turn saves life by avoiding small and major motor vehicle collisions.
Also read about EBD - Electronic Brake Force Distribution System - A subsystem of ABS technology.