A.B.S. quick links
Hydraulic Anti-lock braking systems as fitted to cars and light commercial vehicles.
The ABS controls braking forces by controlling the vehicle's brake system hydraulic pressure to prevent the road wheels from locking up during heavy braking forces. The braking force is controlled by a combination of factors.
ABS, an explanation by Bosch
ABS (Anti Lock Braking) is sometimes referred to as an anti-skid system. The system is designed to prevent the locking of a vehicles wheels while braking., especially on slippery road surfaces.
The main advantage of and ABS system is that it can optimise the available braking efficiency on most surfaces and bring the vehicle to a safe and controlled stop in the shortest distance.
Heavy Vehicle ABS
An overview of HGV air braking A.B.S. systems. Heavy vehicles use compressed air to operate their braking system due to the size and weight of the vehicle requiring larger braking forces.
The ABS system, monitors individual wheel speeds many times per second. When braking, if the ABS control unit detects the wheel is slowing down too much (about to skid), it momentarily release the brakes to regain traction. This is also done many times per second. This momentary release in small pulses is called modulation.
The ABS is there to provide directional stability under heavy braking, allowing some degree of steering and reducing the stopping distance that would otherwise be very long if the vehicle was in a skid.