"ABS" is the abbreviation of "Anti-lock Break System" or "Anti-skid Break System" in English, and the Chinese translation is "anti-lock braking system" or "anti-skid braking system". It is a safety brake control system with the advantages of anti-skid and anti-lock. If a car is not equipped with an ABS system, in the event of an emergency, it will not have time to slow down the brakes step by step and will have to step on the vehicle to death. At this time, the wheels are easy to lock up, and combined with the inertia of the vehicle's sprint, dangerous situations such as sideslip, deviation, and uncontrollable direction may occur. On a car equipped with ABS, when the wheels are about to reach the next locking point, the brakes can act 60 to 120 times in one second, which is equivalent to constantly braking and relaxing, which is similar to mechanical "point braking". Therefore, loss of direction and wheel slip during emergency braking can be avoided, so that the wheels are not locked during braking, and the tires do not rub against the ground at one point, increasing the friction and making the braking efficiency reach more than 90%.
In a four-wheel drive vehicle, all four wheels may slip and the speed reference of the ABS system cannot be measured by the tire speed sensor. Acceleration and deceleration information comes from a longitudinal accelerometer, which may be a separate sensor, a PCB-mounted component integrated in the ABS controller, or in a separate sensor group. Typically, the measurement range of an accelerometer is 1g to 2g; the compensation stability is greater than 100mg over temperature and time; the frequency range is typically 50Hz. Products suitable for this system: SCA320 SCA620 SCA610 SCA220 (module), etc.
[Repost] ABS system and working principle Braking performance is one of the main functions of a car, which is related to driving safety (a bit nonsense, but how many people have really paid attention to this when buying a car, especially some small-displacement cars). The most basic indicators to evaluate the braking performance of a car are braking acceleration, braking distance, braking time and directional stability during braking. ABS (Ant-ilock Brake System) history: The design idea of ??the braking force adjustment device was proposed in the late 1920s, when someone obtained a patent in this area (I don’t know who it was specifically). In the 1950s, the world's first anti-lock braking system, ABS, came out in 1950 and was first used on aircraft in the aviation field. Knorr Company (located in Munich, this company is the world's largest company famous for the production of braking systems) company's anti-lock brakes (ABS) began to be used on trains. The purely mechanical test receiving and recording devices at that time could not meet the higher requirements of automotive technology, so the effect of automotive ABS at that time was not very good. After a lot of experimental research, it was finally concluded: "Sensors for testing the wheel rotation speed and controllers for adjusting the rotation speed are indispensable to achieve the goal." This is an important theoretical basis for the development of automotive ABS systems! In the 1970s, Mercedes-Benz began to envision and announced in the press that it would use electronically controlled ABS in cars, trucks and buses, but there was no mature, mass-produced product yet. In 1978, Mercedes-Benz installed ABS on its S-Class luxury sedan for the first time. In 1984, ABS began to be equipped in batches on S-class, SL-class sedans and 190E gasoline-injection cars. From October 1992 to the present, ABS has become the basic equipment of all types of cars in Germany. At present, the latest ABS has developed to the fifth generation. Today's ABS also has many functions, such as: 1. Electronic Traction System (ETS).
2. Drive anti-skid adjustment device (ASR) 3. Electronic stability program (ESP) 4. Auxiliary brake Let’s talk about the classification of ABS: According to mechanical and electronic classification, the two have the following differences: 1. Electronic ABS is designed according to different models Yes, its installation requires professional skills. If you switch to another vehicle, you must change its circuit design and battery capacity, which is not universal; mechanical ABS is highly versatile and can be used on vehicles with hydraulic brake devices. It can be switched from one vehicle to another and installation only takes 30 minutes. 2. Electronic ABS is large in size, and the finished vehicle may not have enough space to install electronic ABS. In contrast, mechanical ABS is smaller in size and takes up less space. 3. Electronic ABS starts working when the wheels are locked, and works 6 to 12 times per second; mechanical ABS starts working when the brakes are applied, and can work 60 to 120 times per second depending on the vehicle speed. 4. The cost of electronic ABS is higher. In comparison, using mechanical ABS is more economical and practical. According to the classification of control channels, there are the following types: Four-channel type, features: high adhesion coefficient utilization, and the maximum adhesion of each wheel can be utilized to the greatest extent during braking. However, if the adhesion coefficients of the left and right wheels of the car are greatly different (such as water or ice on the road surface), it will affect the stability of the car's braking direction. Guangzhou Honda uses a four-channel ABS device. Three-channel type, features: The car has good directional stability when braking under various conditions. Three-channel ABS is commonly used in cars. Two-channel type. Features: It is difficult for two-channel ABS to take into account all aspects of directional stability, steering control and braking performance. Currently, few one-channel ABS is used. Features: simple structure, low cost, etc., in light trucks widely used. The basic components of the anti-lock braking system: ABS usually consists of a wheel speed sensor, a brake pressure regulator, an electronic control device and an ABS warning light. In different ABS systems, the structure and work of the brake pressure regulator The principles are often different, and the internal structure and control logic of the electronic control device may also be different. All kinds of ABS are the same in the following aspects: (1) ABS only prevents wheels that tend to lock during braking after the car's speed exceeds a certain level (such as 5km/h or 8km/h). Lock brake pressure adjustment. (2) During the braking process, only when the controlled wheel tends to lock, ABS will perform anti-lock adjustment on the braking pressure of the wheel that tends to lock; when the controlled wheel has not yet tended to lock, ABS will , the braking process is exactly the same as that of the conventional braking system (3) ABS has a self-diagnostic function, which can monitor the working conditions of the system. Once a fault is found that affects the normal operation of the system, the ABS will be automatically turned off. And the ABS warning light is illuminated to send a warning signal to the driver, and the car's braking system can still brake like a conventional braking system. ABS usage characteristics: 1. When braking on a road with low adhesion coefficient, the brake pedal should be depressed with one foot. 2. It can stop within the shortest braking distance. 3. The car has high directional stability when braking. Finally. , again, no matter how good the safety equipment is, it cannot compare to careful driving and superb driving skills! So don’t be too superstitious about these equipment, life is precious!