How Does ABS Work?
3 Answers
ABS works as follows: during the braking process of a vehicle, the wheel speed sensors continuously send the speed signals of each wheel to the ABS electronic control unit in real time. The ABS electronic control unit processes the signals from the four speed sensors according to the preset control logic, calculates the vehicle's reference speed, individual wheel speeds, and deceleration, and determines the slip rate of each wheel. ABS, or Anti-lock Braking System, controls the braking force in real time during emergency braking, ensuring the vehicle maintains good directional stability and maneuverability, preventing skidding and deviation, and enhancing the safety performance during braking. The ABS system includes a hydraulic servo braking system, brake master cylinder, brake wheel cylinders, vacuum booster, and pipelines, as well as an electronic control unit, sensors, pressure regulator, warning lights, and other components.
As someone who enjoys tinkering with automotive systems, I have a good understanding of how ABS works. Simply put, ABS stands for Anti-lock Braking System, which electronically prevents the wheels from locking up during emergency braking. It mainly consists of wheel speed sensors, an Electronic Control Unit (ECU), and hydraulic modulator valves. While driving, the sensors continuously monitor the speed of each wheel; if a wheel suddenly decelerates too rapidly, the ECU detects a risk of lock-up and commands the modulator valves to rapidly release and restore brake pressure, performing a pulsing braking action. This process happens multiple times per second, allowing the wheels to keep rotating so you can steer to avoid obstacles. Not only does this reduce braking distance, but it also prevents skidding on slippery surfaces. Think about it—many modern vehicles have even developed Electronic Stability Control based on ABS, which can additionally correct understeer or oversteer, making driving much safer.
Once while I was driving in a hurry, an animal suddenly darted out in front of me. I slammed on the brakes but didn't lose control, and the car came to a steady stop. At that moment, I felt the brake pedal vibrating—that was the ABS at work. The principle of ABS is to prevent the wheels from completely locking up and skidding during emergency braking. It uses sensors to monitor wheel speed, and if any abnormality is detected, the control unit rapidly pulses the brakes, allowing the wheels to maintain slight rotation and grip. This way, even in rain or snow, the car won't skid off the road and you can still steer to avoid danger. When buying a car, pay attention to the ABS status and check if the ABS light on the dashboard is on. Proper maintenance can save lives.
