Changan's L3 autonomous driving mass production experience is successful, and China's smart cars have reached a new milestone

I have test-driven many Changan brand models before, especially the L2-level advanced driver assistance systems equipped in these models, which is the focus of my attention. Although the models I test-driven were fuel models, Changan Automobile's matching degree of L2-level advanced driver assistance should be the best among the current domestic traditional automobile brands. Compared with some other brands that basically simply adapt the suppliers' products, Changan Automobile has carried out in-depth secondary development based on the purchased hardware and software, which also provides a solid foundation for the mass production of L3 autonomous driving.

Many people have heard too much about L2, but rarely about L3 advanced assisted driving systems. L3 autonomous driving technology is conditional autonomous driving. When the system meets the design operating conditions, it can perform all dynamic driving tasks (including environmental perception, steering wheel and acceleration and deceleration control). When the design operating conditions are about to be unsatisfied, the system requests human users to take over. This is also the watershed between "assisted driving" and "autonomous driving", which means that part of the driving responsibility has shifted from people to autonomous driving systems for the first time, marking that the Chinese automotive industry has entered a new era of autonomous driving.

Changan Automobile's L3 advanced driver assistance system, which is ready for mass production, is based on 5 millimeter-wave radars, 6 cameras, and 12 ultrasonic radars as the main sensors. Changan Automobile's L3 autonomous driving system has a sensing range covering 3 360-degree external environment perceptions, integrating 3 sensor systems with different physical characteristics, with 5-fold sensing redundancy in the front, a maximum detection distance of more than 200 meters, and a measurement accuracy of up to 10 centimeters, which can effectively identify vehicles, pedestrians, cyclists and other targets and obstacles in the vehicle driving environment.

At the same time, it can sense the driver's field of vision, fatigue and other states, providing a reliable basis for the intelligent decision-making of the autonomous driving system. It can also effectively identify information such as lane lines, guardrails, traffic signs, etc., and combine the road information of high-precision maps and ADAS maps. It can obtain road information within a range of up to 8 kilometers in real time, achieve lane-level high-precision positioning and precise path planning, and effectively ensure the accuracy of autonomous driving tasks.

Changan Automobile's L3 autonomous driving technology mainly solves the problem of assisted driving in low-speed congested road conditions and high-speed driving. First of all, it can free the eyes to a certain extent in low-speed congested road conditions, and can maintain a safe distance from the vehicle in front to drive automatically, freeing the driver's eyes. To a certain extent, the driver can play with the mobile phone or watch the car computer. The entertainment functions restricted in the manual driving mode are also allowed to be used by the driver; in addition, during the automatic driving process in congested conditions, the system will realize that the vehicle will slow down and stop and restart following the vehicle in front. Within 3 minutes of parking, it can automatically start following the vehicle in front; when the adjacent vehicle cuts in front of the vehicle, the system automatically adjusts the speed to maintain a safe distance from the cutting vehicle.

In the driving conditions of highways and urban expressways with speeds exceeding 40 kilometers per hour, the system will maintain the vehicle speed and steering control, remind the driver to resume monitoring the road environment ahead, and maintain smooth driving in the lane after the driver status monitoring system confirms that the driver's eyes have resumed monitoring. Secondly, when the vehicle approaches a curve, it automatically adjusts to a safe cornering speed to maintain safe driving. Moreover, when the vehicle speed is higher than 50km/h, after the driver turns on the turn signal, the system monitors the feasibility of lane change and controls the vehicle to automatically change lanes to the adjacent lane in the direction of the turn signal. During the lane change, the driver's hands and feet are freed, but the driver must not take his eyes off and must keep monitoring the driving environment. If it is detected that the vehicle is following the vehicle in front for a long time (its actual speed is less than the set speed), the system will actively remind the driver to change lanes to an available target lane, and the driver will automatically change lanes after confirmation. During the lane change, the driver's hands and feet are freed, but the driver must not take his eyes off and must keep monitoring the driving environment.

As early as 2009, Changan had realized the importance of autonomous driving technology and started the overall layout and planning of autonomous driving, and began to form a team to develop autonomous driving vehicles. So far, Changan Automobile has mastered more than 200 intelligent core technologies, and more than 70 intelligent functions are installed on mass-produced models, of which more than 21 are domestic firsts. The mass production of Changan Automobile's L3-level autonomous driving marks the transition of Changan Automobile's L3-level autonomous driving from the technical demonstration of 2,000km unmanned driving tests to the real realization of mass production, marking another major achievement of the Beidou Tianshu strategy.