In November this year, a debate between He Xiaopeng and Yu Chengdong on AEB (Autonomous Emergency Braking, automatic emergency braking system) brought this safety technology to the forefront and aroused the industry's attention to automobile safety. The basic technical principle of
AEB is that the vehicle monitors the driving environment ahead in real time through sensors such as cameras, millimeter-wave radar, and lidar. It will actively brake when encountering unexpected dangers or when the actual distance to objects or pedestrians in front is less than the set safe distance. ; If the actual distance is greater than or equal to the safe distance, the system may use visual, auditory and other methods to alert the driver.
With the implementation and popularization of intelligent driving, AEB has become a standard feature of more and more models while developing towards higher performance. Data shows that among the new energy passenger cars launched from January to August 2023, most have implemented the AEB function as standard for the entire series.
However, the much-discussed AEB technology is only one of the active safety technologies in automobiles. The automobile safety system covers both active safety systems and passive safety systems. From the perspective of the entire vehicle, if the safety of the car only relies on AEB, It's obviously not enough. How does
ensure smart driving safety?
Since this year, the penetration rate of intelligent driving in the entire automobile industry has increased rapidly. According to data from the Ministry of Industry and Information Technology, the penetration rate of new L2 passenger cars with combined assisted driving functions will reach 34.9% in 2022, and is expected to reach 70% by 2025.
As the penetration of intelligent driving capabilities accelerates, intelligent driving safety has become an issue that major manufacturers need to pay attention to. Whether it is the safety redundancy brought by multiple sensors or the improvement of AEB performance, they are all manifestations of intelligent driving safety.
In practical applications, smart driving safety is actually more subdivided. Take the Volkswagen IQ. Drive smart driving steward as an example, which includes various intelligent driving assistance systems that can actively avoid dangers, such as Travel Assist full-speed driving assistance system and Front Assist front safety system.
For example, when a vehicle encounters a vehicle in front that suddenly slows down or changes lanes, or encounters cyclists and pedestrians suddenly entering the lane, and the driver fails to respond in time, ID. will trigger the active safety function - āThrough the front multi-function camera and ACC millimeter-wave radar, it can detect vehicles and pedestrians that are decelerating or stationary in the same direction ahead at a speed of up to about 60 km/h, prompt the driver and intervene in the brakes in time to maximize Avoid accidents or mitigate damage.
In addition, its Emergency Assist emergency assistance system can monitor whether the driver is driving the vehicle normally when the driving assistance is turned on, and remind the driver to take over the vehicle through system prompts and slight braking.
If the driver still fails to resume driving, the vehicle will gradually control the vehicle to stop in the lane through driving assistance systems such as lane keeping system and adaptive cruise, illuminate the emergency warning lights and unlock the doors, while also using the SOS emergency call function Will proactively contact the call center.
In addition to the active safety configuration to avoid accidents as much as possible, the passive safety of starting the car in the face of emergencies is equally important.
Under normal circumstances, the activation of passive safety mechanisms in cars is mostly due to collisions, so car companies mostly work on vehicle structures, airbags, seat belts, etc. to reduce the risk of collisions.
Take the ID.7 VIZZION launched this month as an example. Its body adopts a high-rigidity design, with high-strength and ultra-high-strength steel accounting for up to 81%. It also designs a "sandwich" sill structure and two reinforcements made of aircraft carrier-grade materials. Cross beams provide further protection for the body and battery.
"When a serious collision occurs, within 150 milliseconds of the accident, the vehicle will complete the door unlocking through the sensor recognition status, activate the airbag and the negative controller inside the battery pack to cut off the power and explode the device, ensuring that the people in the car have the ability to escape. , to facilitate rescue by people outside the vehicle. If a continuous collision occurs and the vehicle is not at rest, then ID. will provide active braking after the initial collision through the cooperation of the sensor and braking unit (ESC, ESP) and brake as soon as possible after the initial collision. Stop the vehicle to avoid the risk of subsequent accidents," said Han Tao, senior manager of Volkswagen brand technical training.
Three-point safety belt with tubular detonation device
It is worth mentioning that among the devices displayed on site, Volkswagen designed the common seat belt into a "three-point safety belt with tubular detonation device", which can be used in collisions It is triggered when an accident occurs and cooperates with the seat belt tightening device to tighten the shoulders and abdomen of the front passenger from two directions, fixing the occupant in the seat, and cooperates with the air bag to reduce the damage caused by the collision.
Battery safety is also particularly important.
In addition to the safety of smart driving, as the core component of electric vehicles, power battery safety is also an important part of the safety of the entire vehicle.
As early as 2018, Volkswagen established a team of battery experts of about 300 people and conducted trial production, various designs, debugging, etc. in the Volkswagen factory.
In 2021, the Volkswagen Group stated that in the next 10 years, it will reduce the cost of electric vehicles and the supply of core components through full adjustments to the supply chain. In July of the following year, Volkswagen established PowerCo, an independent battery company, to integrate the Volkswagen Group's global battery business along the value chain - from raw material supply and development to the construction and operation of super factories.
In November this year, the Volkswagen Groupās first wholly-owned battery pack production plant in China was put into operation in Hefei. The batteries produced will be exclusively used for the Volkswagen ID pure electric series and the upcoming pure electric models on the MEB platform.
It is reported that in addition to the battery part, Volkswagen can independently control the battery module design, battery management system, battery pack, etc., and has gradually formed a system for battery safety.
"The battery pack adopts a sophisticated anti-corrosion design. The sealing ring, liquid sealant and wax provide triple protection for the battery pack. The surface of the water-cooling plate has also been treated with anti-corrosion, which can prevent the battery pack from being corroded from the outside to the inside." Volkswagen technology expert Zhang Bo said.
Judging from the battery pack on display, its shell is designed with aluminum alloy, and the bottom is an integrally stamped high-strength aluminum guard plate to protect the battery pack from impact damage such as potholes on the road, flying stones, etc. The lower shell of the
aluminum alloy battery pack has a honeycomb design, and adopts a welded form that combines profile beams and longitudinal beams, which not only ensures the high strength of the battery pack, but also makes the battery pack both lightweight and high energy density, making it safe and The battery life is suitable for both purposes; in addition, the high-strength aluminum guard plate is integrally stamped at the bottom to protect the battery pack from impact damage such as potholes, flying stones, etc. The safety of the
battery itself is only passive safety. In order to reduce the occurrence of battery accidents and improve the safety of the entire vehicle, engineers will add an additional safety barrier when designing the battery management system, also called active safety.
Under normal circumstances, when designing a battery system, manufacturers will use temperature sensors to detect the operating temperature of the battery, the current and voltage of the battery system and battery cells, and transmit the data to the vehicle processor in real time. Once the battery "thermal runaway" occurs, early stage Characteristics such as abnormal temperature and zero battery cell voltage will immediately cut off the working circuit, and at the same time, the fault will be displayed on the control screen to remind the car owner to deal with it.
It is reported that Volkswagenās battery management system (BMS) also has a thermal diffusion monitoring function, which can monitor battery status and promptly alert users when encountering abnormal conditions. When a high-voltage short circuit occurs, the system will actively cut off the high-voltage system power supply to further reduce the risk of heat diffusion.
In addition, the high-voltage power distribution system, combined with vehicle collision signal monitoring, can actively cut off the high-voltage circuit when the vehicle collides, avoiding the risk of short circuit of the high-voltage battery.
From the intelligent driving system to the vehicle and battery levels, in the era of electric vehicles, vehicle safety is more complex. Battery safety alone is enough for car companies to work hard to overcome all aspects of problems. Although Volkswagen has not yet fully penetrated into all aspects of the battery industry, Volkswagen China's investment in Guoxuan Hi-Tech in 2021 and the Volkswagen Group's establishment of a battery company in 2022 indicate that this company is continuously penetrating the battery field.
In recent years, more and more car companies have penetrated into the battery industry chain. BYD has blade batteries, Geely has launched Aegis batteries, Changan's "Golden Bell", etc. Even the new energy brand Ji Krypton has recently released a self-developed self-developed battery. Create a āgold brick batteryā.
Zhang Bo told TMTpost Media APP that going deep into the battery industry chain can not only better control battery costs, but also enable in-depth research on all aspects of batteries, especially in terms of safety, which can be more autonomous and controllable.
It is worth noting that the timing of Volkswagenās concentrated safety promotion coincides with the launch of the Volkswagen ID.7 VIZZION, which is enough to understand its intention.
Whether it is the safety challenges brought by batteries or smart driving that further enhances the industry's emphasis on safety, car safety is always a process that is infinitely close to 100%. This difficult but correct thing is a required course for every car company , Volkswagen is no exception.
(This article was first published on Titanium Media App, authorļ½Xiao Man, editorļ½Zhang Min)
