Why do car self-driving technology use so many sensors?

“As we all know, there are 5 levels of autonomous driving technology. The higher the level, the more work the assistance system does on behalf of the driver. Level 5 represents fully automated driving, which enables unmanned driving in any environment and situation. When the automation level reaches level 5, there is no need for the driver to control the vehicle at any time. In human terms, when autonomous driving reaches level 5, humans don’t have to be drivers, they can do other things like passengers, and machines are drivers.

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If I had to answer that question in three words, it would be safer, safer, safer, safer. Important things said 5 times!

As we all know, there are 5 levels of autonomous driving technology. The higher the level, the more work the assistance system does on behalf of the driver. Level 5 represents fully automated driving, which enables unmanned driving in any environment and situation. When the automation level reaches level 5, there is no need for the driver to control the vehicle at any time. In human terms, when autonomous driving reaches level 5, humans don’t have to be drivers, they can do other things like passengers, and machines are drivers.

So the question is, how can we ensure that machine driving is safer or even safer than human driving. This is where the sensor comes in.

The mainstream sensor products currently used in autonomous driving mainly include lidar, millimeter-wave radar, ultrasonic radar and cameras. Their main function is to know the surrounding environment, make correct judgments based on the collected information, and then perform corresponding operations.

Lidar is a comprehensive light detection and measurement system. By transmitting and receiving laser beams, it analyzes the return time after the laser beam encounters the target object, and calculates the relative distance to the target object. It scans the surrounding environment and generates a high-precision 3D image of the surrounding environment. It is also key to becoming Level 3-5 autonomous driving.

The working principle of ultrasonic radar is to send out ultrasonic waves through the ultrasonic transmitter, and measure the distance from the time when the receiver receives the transmitted ultrasonic waves. Ultrasonic radar is low-cost, has advantages in short-distance measurement, and has high accuracy, which is very suitable for parking systems. However, it has a limited measuring distance and is easily affected by the external environment.

In-vehicle cameras are the main visual sensor for automatic systems and are one of the most mature in-vehicle sensors. After the image is collected by the lens, the photosensitive component circuit and the control component in the camera process the image and convert it into a digital image that can be processed by the computer, so as to realize the perception of the surrounding road conditions of the vehicle.

Millimeter-wave radar is the core sensor of the autonomous driving system. Among them, the 77GHz automotive radar system has broad prospects. Its great advantages are: high precision and excellent scalability from short to long distances, enabling a range of driver assistance functions. But correspondingly, its technical complexity is also very high. The 24GHz automotive radar, on the other hand, makes up for this with its ease of use, while also enabling widely requested functions such as automatic brake assist or blind-spot detection.

These sensors are like the “eyes,” ears, “hands”, “feet” and other human organs of autonomous vehicles. They can see six roads, listen to all directions, cooperate flexibly, respond in time, make prediction and planning decisions, and finally realize automatic driving. All passengers arrived safely at their destination.

Finally, a few digressions, in addition to self-driving cars, traditional cars also use a lot of sensors. They can be divided into 8 categories according to their functions: pressure sensor, position sensor, temperature sensor, acceleration sensor, angular velocity sensor, flow sensor, odor concentration sensor and liquid level sensor. Automotive sensors are mainly used in powertrain systems, body control systems and chassis systems, where they are responsible for information collection and transmission. Complete the Electronic control of the body.

For more information about autonomous driving sensors, you can go to Infineon’s official Zhihu account to view it. Scan the QR code below to open Zhihu and follow Infineon, or directly search for “Infineon” in Zhihu.