The development of the blue ocean breakthrough and shallow automatic driving lidar.

When it comes to autopilot, many friends think of all kinds of sensors, high-precision maps, GPS and so on. In the end, autopilot is as unassailable as a fully armed warrior. In this case, laser radar plays a very important role, so what is the existence of laser radar, and what are the characteristics of it compared with millimeter wave? Then we're going to look at the laser radar.
What is the laser radar?
The laser radar, called LiDAR, is a system of laser, GPS global positioning and inertial measurement devices. It is used to obtain data and generate an accurate digital model. The combination of these three technologies can highly accurately locate the location of the laser beam. Compared with other products, laser radar can give full play to the advantages of precision, speed and efficiency.
Laser radar is equivalent to the human eye:
Laser radar is still a kind of popular sensor, and other sensors include camera, ultrasonic, infrared, millimeter wave radar and so on. Its biggest feature is that it can generate three-dimensional position information, and can quickly determine the position, size, external morphology and even material of the object, and obtain data and generate it at the same time. A precise digital model.
In addition to the camera and other sensors, in addition to generating a three-dimensional position model, the laser radar has a far farther detection distance, higher measurement precision, and more sensitive response speed, and does not receive the influence of ambient light. Therefore, lidar is not only equivalent to a pair of eyes for the car, but also a pair of eyes.
The current types of laser radar:
From the type, the laser radar can be divided into mechanical laser radar and solid state laser radar. The mechanical laser radar has the control of the laser emission angle, while the solid state depends on the electronic components to control the laser emission angle. Compared with the traditional mechanical system, solid state radar has larger scanning speed and faster response speed, and the cost has also been effectively controlled.
From the number of internal harness, laser radar can be divided into single beam and multi beam laser radar. The traditional Dan Xianshu radar scan only produces a scan line at once, so it generates plane information. Nevertheless, the single line radar has wide application space because of its faster measurement speed, such as terrain mapping and so on.
But the traditional single line radar is not suitable for automatic driving because of its small scanning angle. How to solve this problem and increase wiring harness is the simplest and direct way. The more wiring harness, the wider the detection range, and the more accurate the data. So the current laser radar products on the market have 4 wire bundles, 8 wire bundles, 16 wire bundles, 32 wire bundles, and 64 wire bundles, and so on. Of course, the 128 wire beam laser radar, which has a more abnormal function, has also appeared as time goes on.
"Love to kill" the laser and millimeter wave:
Laser radar and millimeter wave radar are in love with each other. This millimeter wave can be effectively made up for the characteristics that the radar can not work in the rain and snow weather. At the same time, the directivity is better, but compared to the accuracy of the lidar for middle and remote objects, the millimeter wave is one raise, for example, a few hundred meters away. Millimeter wave radar may only detect obstacles, but what is specific is beyond its scope of work.
But in today's conditions, the laser radar and the millimeter wave have completed a very good compatibility. Together with the camera, they form the "three swordsman" of the sensor. Their functions are determined by the nature of their own, and the three are indispensable.
A millimeter wave radar is mainly used or detected in obstacles; it is difficult to get a model of a three-dimensional object, including its interference with the environment, which is also more dependent on the impact of this light, but the camera is very good for the classification and tracking of objects; laser radar is widely used for positioning, obstacle detection, object classification, dynamic objects. Tracking and other applications.
Is the precision of a laser radar higher and better?
Many friends think that, with the rapid development of science and technology, the accuracy of radar is higher and better. But I don't know that it involves a misunderstanding of deviation. Taking laser radar as an example, the data obtained by the laser radar is the key to the monitoring of the type of obstacle and the object in motion. If the precision is too poor to be recognized, we can all understand. But if the precision is too high, it will put forward quite high requirements for the other parts of the laser radar and even the auto driving model. Besides the amount of work that is not needed at all, the operating cost will also be greatly increased and may even shorten the life of the vehicle. Right amount is good.
What do you do without the automatic driving of a laser radar?

Automatic driving must be equipped with lidar. If lidar can control cost effectively, laser assistant function of low ADAS number also needs laser radar. The reason is that the limitations of webcam based ADAS and autonomous driving system or the use of millimeter wave alone are quite large.
First of all, the field of view problem. In order to ensure enough detection distance, the angle of the field of view is not too large, which leads to a very large transverse blind area. The use of the wide angle lens or the fish eye also knows that the edge distortion is very serious, the needle has some manufacturers to launch multi camera working mode, even if so, it can not solve the problem of close blind area, the same multi camera will have overlapping area, this will increase the complexity of the algorithm, use filter re channel. Increase the system response time and increase the cost.
Next is the low speed problem. The camera doesn't perform well for the vehicle at low speed, even for static targets and slow moving targets. The millimeter wave may only be able to identify obstacles, and it is difficult to be very hard on whether it is a person or a barrier, without a laser radar, or even a substitute for a laser radar.
Of course, to solve the problem of automatic driving, the improvement and matching of industrial chain is also a problem that can not be ignored. According to the news of the author, the laser radar, autopilot chip and electric vehicle battery group in the next few years are more or less likely to encounter problems that can not be matched by capacity. It is also a big problem for high cost control. Therefore, besides the hard conditions such as 5G, the road of automatic driving still has a long way to go. The mirror image of lidar is still unknown.
From the visible, no laser radar, the development of auto driver will can't do anything. But even so, the safety of autopilot is particularly important, even if the current safety rate is 99%, because the remaining 1% is likely to be a person, and this is a lesson in the previous Uber, Arizona, America. We hope that the future autopilot can appear in front of us with a better posture, but it is not one day cold, and the completion of Rome is not a single day. We will be patient with this long road of exploration.