The braking purpose is manipulative premise shortest braking distance to ensure the stabilization of vehicle.
Affect the braking effect of the main factors car itself may provide a braking force, the adhesion and the inertia of the tire contact with the ground in three aspects.
Obviously in the same road surface, under the same operating conditions (speed, load), the car itself may provide a braking force is greater (in the non-locking of the wheels under the premise), the shorter the braking distance. Similarly, different road conditions, the greater the adhesion coefficient road braking distance, the shorter. On the same road, the same braking strength, different speed, different load obviously different braking effect, the greater the inertia of the car the longer braking distances.
The braking force inertia two factors can artificially control or master. Coefficient of adhesion between tire and road is only human can not control. A lot of practice and experiments show that: the tire and road adhesion coefficient is not only related to pavement materials, tire pressure, tire wear, and have a great relationship with the relative motion of the tire and the road braking. Analysis the braking tire left on the ground traces will be found: the start braking tire left on the ground embossing traces As the brake intensity increases patterns and more dense, and the last to leave a "drag printed. "Embossed" stage, the tire braking tire not only relative to the ground sliding and still "rolling". "Drag India stage tire completely with the ground sliding.
To illustrate the procedure the braking the ground tire with the ground "drag slip", we introduce the concept of a "sliding rate of S".
S = V-W * R / V * 100%
Obviously, the tire pure rolling on the ground, V = W * R S of = 0, when the tire on the ground sliding "pure" drag, and W * R = 0, S = 100% braking, S = 100% we call the tires "Hugging". Between S and 0 and 100%, clear that the tire and the ground both scroll another drag slip. The larger the sliding rate S tires in the road "drag slip" the greater the degree.（Source：Sinotruk）