What is ABS?
2 Answers
ABS, short for Anti-lock Braking System, functions to automatically control the braking force during vehicle braking, preventing the wheels from locking up and maintaining a state of rolling while slipping (with a slip ratio of around 20%). This ensures that the adhesion between the wheels and the road surface remains at its maximum. The ABS sensor is located on the inner side of the vehicle's tires and can be seen when the car is lifted. The ABS system mainly consists of four components: wheel speed sensor, electronic control unit (ECU), hydraulic unit, and ABS warning light. The wheel speed sensor detects the motion state of the wheels, emitting sinusoidal electronic pulse AC signals. These signals are then processed by a modulator, converted into digital signals, and transmitted to the electronic control unit. The electronic central control unit (ECU) receives input signals from the wheel speed sensors, calculates the wheel speed, vehicle speed, and slip ratio based on these parameters, and determines the wheel state according to the slip ratio. It then issues control commands to the hydraulic unit. The hydraulic unit adjusts the pressure in the brake lines according to the control commands, with the adjustment process including pressure holding, pressure increase, and pressure decrease. The ABS warning light alerts the driver to any system malfunctions. If the ABS warning light is on, it is advisable not to continue driving. This is because an illuminated ABS light indicates a malfunction in the vehicle's anti-lock braking system. During emergency braking, if the wheels lock up, the vehicle may lose control and skid, making it difficult for the driver to decelerate or adjust the vehicle's trajectory, posing significant safety risks.
I've been driving for thirty years, and ABS stands for Anti-lock Braking System, primarily designed to prevent wheels from locking up and skidding during emergency braking. It uses sensors to monitor the speed of each wheel. If the system detects that a wheel is about to lock, the electronic control unit instantly adjusts the brake pressure to keep the wheel rolling. This allows you to maintain steering control even when braking hard, helping you avoid obstacles and loss of control. Especially on wet or snowy roads, ABS can reduce braking distance and the risk of rollover. Introduced to the market by manufacturers like Mercedes-Benz in the 1970s, it is now a standard feature in almost every new car. Remember, when ABS activates, the brake pedal may vibrate, which is normal. If the ABS warning light comes on, it could indicate dirty sensors or wiring issues, so address it promptly to ensure safe driving.
