The braking distance of the vehicle is the direct embodiment of the braking performance. The shorter the braking distance, the better the efficiency of the braking system, and the corresponding safety will be better under the condition of best effort. So what factors will affect the braking distance? Now I'll take a look with you.
1. Suspension system
In general, it is difficult to connect the suspension system with the braking distance. In fact, the suspension system has an impact on the braking distance. During emergency braking, the forward movement of the vehicle's center of gravity will compress the front suspension. If the support of the front suspension is insufficient, the forward movement of the vehicle's center of gravity will be too large, which will reduce the adhesion of the rear wheels, weaken the braking effect of the rear wheels, and increase the braking distance. The front of some cars sinks seriously when braking, which is the performance of poor support of the front suspension.
2. Vehicle weight
The greater the vehicle weight, the greater the inertia, the more difficult it is to stop, so the vehicle weight also has a direct impact on the braking distance. However, it does not mean that heavy vehicles must have a longer braking distance than light vehicles. For example, the weight of some performance vehicles is much greater than that of household class a vehicles, but their braking performance is much better, because tires and braking system should be considered. The influence of vehicle weight on braking distance is mainly reflected in that for the same vehicle, the greater the loading mass under the same braking system, the shorter the braking distance.
3. Tire
The tire is the carrier of the braking system. The better the tire adhesion, the more braking force can be obtained during braking, and the braking distance can be shortened. Generally, the factor affecting the braking distance of household vehicles is the width of the tire. The wider the tire, the larger the grounding area and the greater the ground braking force.
4. Braking force
Automobile braking force is divided into two types, one is brake braking force, the other is ground braking force. Brake braking force is the braking force that the braking system can provide on the brake disc or brake drum. The ground braking force refers to the braking force formed by the ground on the tire. Obviously, the ground braking force between the two is the direct factor determining the braking performance, and the brake braking force determines whether the maximum ground braking force can be obtained. In popular terms, the friction between the wheel and the ground is the final factor determining the braking distance, and the maximum braking force generated by the braking system determines whether the wheel can form the maximum friction with the ground. The braking force of the car's brake is greater than the ground braking force. As long as you can lock the wheels when you step on the brake or trigger ABS on a dry and flat road, the braking force of the brake is qualified.
5. Electronic auxiliary system
The first thing to say is ABS. ABS is the abbreviation of anti lock braking system, which can prevent tire locking, so as to ensure the control of the vehicle during emergency braking. The study found that when the slip ratio between the wheel and the ground is between 15% - 20%, the ground braking force is the largest and the braking effect is the best. Therefore, people control the slip ratio of the locking tire in this range through the ABS system in order to obtain the best braking effect. Therefore, when the tire is about to lock up due to emergency braking on dry roads, ABS can obtain a shorter braking distance than locking up.
The other is the brake assist system, because some drivers are inexperienced. In an emergency, due to lack of experience, they can't step on the brake pedal with all their strength, which leads to the fact that the braking force actually acting on the brake is too small to give full play to the effect of the braking system. The brake assist system collects the strength and speed of stepping on the brake according to the sensor. When it judges that the driver is making emergency braking, but the braking force is not fully exerted, the system will help you improve the braking force, which is particularly useful for novices.
6. Brake system temperature
It is often seen that the brake discs of some racing cars are red. In fact, these cars use brake pads made of a special material, which can obtain the best performance at a certain high temperature. However, for household vehicles, high temperature is a great reason to affect the braking force. Too high temperature will lead to a sharp decline in the braking force. Therefore, in the continuous downhill section, we should learn to use engine braking to limit the speed and try to avoid stepping on the brake continuously for a long time.
7. Ground conditions
Braking ultimately depends on the friction between the wheel and the ground. The road condition determines the friction between the ground and the wheel. Generally, the braking effect of dry asphalt road is the best, followed by cement road. The braking effect of gravel road, earth road and wet asphalt road is even worse. In particular, some fine sand and gravel are easy to appear on the shoulder of some roads, mainly when the air flow blows to the roadside during driving. After the wheel is pressed on, the sand and gravel will roll between the wheel and the road surface, which will seriously affect the braking effect. Therefore, we must pay attention when driving daily.