An article about automatic emergency braking system

When driving on the highway, the empty road ahead makes you inadvertently distracted. Suddenly, the vehicle in front of you changes lanes and drives directly in front of you and very close to you. You still maintain a fast speed and do not notice the change in traffic conditions. Suddenly, your car starts to emergency brake by itself. You also feel the sudden change in the vehicle's state and find the vehicle in front of the lane. You also decisively step on the brake pedal to keep your vehicle at a safe distance from the vehicle in front. At this time, you silently thank God that when you bought the car, you chose an advanced driver assistance system with an automatic emergency braking system to avoid accidents.

The emergence of advanced driver assistance systems has made driving more interesting and intelligent. Advanced driver assistance systems use various sensors installed on the vehicle (millimeter wave radar, lidar, on-board cameras, etc.) to sense the surrounding environment at any time during driving, collect data, and perform static and dynamic object recognition, detection and tracking. In conjunction with the use of high-precision maps/navigation maps, the system analyzes and calculates road conditions, allowing the driver to be aware of possible dangers in advance.

With the continuous development of advanced driver assistance systems, advanced driver assistance functions are gradually being equipped on entry-level vehicles, and more and more active and safe advanced driver assistance systems are also being installed on vehicles, allowing drivers to drive vehicles more safely and efficiently. Active and safe advanced driver assistance systems can directly make decisions on the vehicle's driving process, allowing the vehicle to maintain balance and stability during driving without the driver's control. In the event of an emergency, it can also make quick judgments before the driver reacts, and avoid or reduce collisions through active braking or emergency avoidance, ensuring the safety of the entire driving process.

As a representative advanced driver assistance system in active safety, the automatic emergency braking system can actively control the braking system to stop the vehicle in time and remind the driver to pay attention to the road conditions when it detects that the vehicle is about to collide. The automatic emergency braking system is rarely used when driving, but it can well protect the lives of drivers and passengers when there is a danger of an imminent collision.

According to a survey conducted by the National Highway Traffic Safety Administration (NTHSA), about 90% of road traffic accidents are caused by driver errors, of which rear-end collisions account for the majority. Among rear-end collisions, 31% of accidents are caused by the driver not stepping on the brake pedal; 49% of accidents are caused by the driver stepping on the brake pedal but the braking force is insufficient; and about 20% of accidents are caused by the driver stepping on the brake pedal and the braking force is sufficient, but the braking distance is insufficient. If the driver can respond to an impending accident 0.5 s in advance, 60% of rear-end collisions, 40% of side collisions and 30% of frontal collisions can be effectively avoided. If the driver can respond to an impending accident 1 s to 2 s in advance, most traffic accidents can be avoided. The emergence of the automatic emergency braking system can predict possible dangers in advance and remind the driver. If necessary, the vehicle can be directly braked for straight driving, which can effectively reduce the possibility of accidents.

In addition to controlling the braking system when the driver does not detect danger, the automatic emergency braking system can also provide auxiliary braking when the driver steps on the brake pedal but it is not enough to prevent a collision, so that the vehicle can be stopped or slowed down in time to ensure that the vehicle does not collide.

The automatic emergency braking system did not appear in recent years. As early as 1938, people discussed the issue of automobile driving safety and applied concepts such as collision, obstacles, and automobile safety to automobile driving theory. The prototype of the automatic emergency braking system thus appeared. In 1960, developed countries represented by Germany, Japan, and the United States began to study active collision avoidance systems, but due to the low level of microwave technology and high hardware costs at the time, there was no technological breakthrough in the active collision avoidance system. It was not until 1980 that the rapid development of radar technology and microcomputer technology promoted a decisive breakthrough in active collision avoidance technology, and the active collision avoidance system officially began to develop rapidly.

The automatic emergency braking system mainly detects vehicles and pedestrians on the road through sensors such as radars and on-board cameras installed in the front grille, bumper, and near the rearview mirror, analyzes the driving status of itself and surrounding traffic participants, and performs calculations. When it detects that danger is about to occur, it will activate the braking system to work, avoid or reduce collisions through active braking or emergency avoidance, and remind the driver to pay attention to road conditions.

The execution of the automatic emergency braking system is mainly divided into three stages: alarm, brake assist, and braking. When the perception system senses possible danger, it can use sound or vibration to remind the driver to pay attention to road conditions and avoid danger; when the driver does not respond, the automatic emergency braking system will enter the pre-filling stage. If the driver steps on the brake pedal at this time, the automatic emergency braking system will assist in increasing the braking force; if the driver still does not respond, the automatic emergency braking system will let the braking system work to avoid possible danger.

The emergence of the automatic emergency braking system provides drivers with a safer driving environment, but can the automatic emergency braking system really ensure 100% safety? First of all, it is certain that the automatic emergency braking system can indeed make the driving process safer, but there will also be some situations such as false triggering. False triggering is mainly because the automatic emergency braking system identifies vehicles, pedestrians, barriers, etc. in the next lane and mistakenly thinks that they are in the vehicle's lane, thus triggering it by mistake.

In addition to false triggering, there may also be a failure of the automatic emergency braking system. If it is just a failure, the driver pays more attention to the road conditions while driving, and the possibility of an accident is not very high. However, if the driver relies too much on the automatic emergency braking system and is distracted while driving, the failure of the automatic emergency braking system will have very serious consequences.

On August 11, 2022, a video went viral online. Two people got off the car in the innermost lane, one squatted behind the car, and the other was about to place a tripod to warn the car behind. Suddenly, a Xiaopeng P7 rushed up and directly hit one of them. It is understood that the owner of the Xiaopeng P7 turned on the advanced driver assistance function at the time. The speed was 80km/h, but the vehicle did not detect anyone in front when the danger was about to occur, and it ran straight through. The owner said that when he used the advanced driver assistance function before, there would be a warning, but this time there was no prompt, and he was distracted at the time.

In this accident, the vehicle's advanced driver assistance system was turned on, but the driver had great trust in the advanced driver assistance system due to its failure, which led to the accident. The automatic emergency braking system, as an advanced driver assistance system in active safety, can participate in the vehicle's driving process. If there is a functional failure, the danger that may result is self-evident.

The emergence of advanced driver assistance systems such as automatic emergency braking systems can make driving safer for drivers, but as drivers, we cannot completely entrust driving safety to advanced driver assistance systems such as automatic emergency braking systems when driving vehicles. The function of advanced driver assistance systems can only be auxiliary!