So what does ABS really stand for?
If you were to ask a motorist what the term “ABS” stands for, he would likely reply “Anti-lock Braking System”. While this is technically correct, a more accurate response would be “Anti-lock Braking Steering control”.
Let’s look into this a little deeper. We all know what ABS does; as the driver presses the brake pedal, the ABS monitors each individual wheel’s speed. Should one or more wheels drop in RPM more than anticipated, the ABS controller assumes that those wheels are skidding, and will promptly command a hydraulic unit to reduce the applied brake pressure to the appropriate wheels. This allows the tires to regain traction and grip the road surface once again. This process repeats itself very rapidly – thus the vibration feedback felt in the brake pedal. On most surfaces, this process allows the tire to be on the verge of lock up so that braking effort is maximized. However, on ice, a locked up wheel is likely to require a shorter distance to come to a stop than a pulsating, ABS modulated wheel. So why have ABS?
The tires on a car perform three functions other than carrying the vehicle’s weight. They accelerate, brake as well as steer it. But a tire will steer and maintain directional stability only while it is rotating. A locked wheel becomes nothing more than a patch of rubber on the road with no lateral control whatsoever. That is usually why drivers without ABS who slam on their brake pedal in a panic situation lock their wheels, slide forward, and may hit whatever is front of them. Turning the steering wheel does nothing as the front wheels cannot provide steering while locked up. However, with ABS, no matter how hard the driver might press on the brake pedal, the wheels keep on turning, allowing the driver to steer his way out of a dangerous situation while braking at the same time.
Although ABS contributes to safety, it is no substitute for a sensible, defensive style of driving. Always adjust your speed to match the road conditions.