The braking process of a car can be divided into four key stages. First is the driver's reaction stage: within approximately 0.3 seconds, the nerve conduction from perceiving danger to pressing the pedal is completed, during which the vehicle decelerates slightly only by wind resistance and mechanical resistance. Second is the brake's idle travel stage: the free play of the pedal is eliminated within about 0.05 to 0.1 seconds, and no braking force is formed at this stage. Third is the braking force growth stage: the hydraulic system builds up pressure within 0.05 to 0.1 seconds to make the brake pads contact the brake disc, and the deceleration starts to increase significantly at this point. The ABS system commonly equipped in modern vehicles dynamically adjusts the braking force during the continuous braking stage to prevent tyre lock-up, while the vacuum booster can shorten the braking force build-up time by about 30%. It is recommended that car owners regularly check the boiling point of brake fluid and the thickness of brake pads to ensure normal response in all stages.
