People look at the road by their eyes, as do self-driving cars. Lidar is the "eye" of a driverless car. With the landing of autonomous driving, the lidar, which was originally used for 3D scanning, has become a necessity for autonomous vehicles, and even determines the evolutionary level of the autonomous driving industry. But in this laser pointer field, which is the key to the industry, domestic products have almost no say.
Lidar cannot be replaced. Lidar is a sensor with its own light source that actively emits laser light and senses the surrounding environment, just like a bat is positioned by ultrasound.
According to the classification of L1-L5 of automatic driving, L3 and below are assisted driving or low-level automatic driving, and L4 and L5 can be regarded as high-level automatic driving or even unmanned driving. At present, autonomous driving is under L3. Millimeter-wave radar and even cameras can meet the visual requirements of cars. Tesla has applied the former. However, in order to develop into a high-level autonomous driving stage, affected by ranging, resolution, accuracy, and comprehensive information, lidar cannot be replaced.
Lidar can accurately measure distance: by obtaining the time the laser pointer hits the object and returns to the receiver, it can be obtained by multiplying the speed of light. Because each beam of light emitted has relative position information, the lidar can use algorithms to generate a high-resolution digital map of the car's surroundings in real time for target tracking and identification. Zhang Zhiwu, general manager of Beike Tianhua, a mainstream domestic lidar company, introduced to the reporter of Science and Technology Daily that the lidar's scanning accuracy is high and there is no distortion. The millimeter-wave radar only knows that there are obstacles in front and cannot accurately describe the size and shape.
The laser data is vector data, and the computer can classify, extract, and process it. It can automatically identify lane lines, barriers, traffic signs, trees, etc. This is also impossible for other sensors.
Lidar is often distinguished by the number of lines, and is usually designed as an exponential level of 2, such as 4-wire, 8-wire, 16-line, 32-line, 64-line, and 128-line top-level test products that have not yet come out. The number of lines refers to the number of laser pointer sources of laser emission light. There are 16 light sources for 16-line products, and so on. Among the self-driving cars that can be put on the road, everyone who involves lidar uses almost all Velodyne products from the United States. This company was founded in 1983 and is located in Silicon Valley. Its lidar products are standard in the industry and account for more than 80% of the market share.