Operating principle of the ABS system (Renault Symbol 1)

The anti-lock braking system (ABS) was developed by Bosch and is designed to prevent wheel locking during sudden braking, which increases the active safety of the car. The system starts working at a speed of about 7 km/h and stops at a speed below 3 km/h, while the car moves without skidding until it comes to a complete stop.

Brakes work most effectively when there is maximum friction between the tires and the road surface. When braking, the tire begins to slip on the road surface and the peripheral speed of the wheel becomes less than the speed of the car.

Tire slip is zero when the wheel rotates freely and 100% when the wheel is locked. Maximum braking efficiency is achieved with a slip coefficient of 15%.

This value of the slip coefficient ensures reliable control and the best stability of the vehicle.

The purpose of the anti-lock braking system is to instantly limit the pressure in the brakes to obtain an optimal coefficient of wheel slip. ABS instantly affects the brake of each wheel, reacting to changes in the properties of the road surface or the load on the wheel.