AI Visual VS Lidar

22 november 2018 - Beijing, China

Consumers today may feel the same as I do. Many high-end words make us feel unprecedented expectations for advertising. "With AI vision navigation technology, high-definition camera, AI intelligent processor, and advanced vision algorithm, real-time capture of the mobile coordinates of the robot in the home environment, accurate positioning and real-time mapping." Is this description high-level and full of technology? How is the development of AI visual navigation? What are the advantages of lidar positioning over the mainstream market? What is the relationship between them? With these questions, let's take a look.

What is navigation first? Simply put, navigation is an important cognitive task to help humans and animals travel long distances through complex worlds without maps. Such long-distance navigation supports both self-localization ("I'm here") and goal representation ("I'm going there").

AI visual navigation system is an emerging navigation method that uses machine vision and other related technologies to identify paths and realize automatic navigation. AI vision navigation system involves interdisciplinary fields such as artificial intelligence, neurobiology, psychophysics, computer science, image processing, pattern recognition and many other fields. The information is extracted from the image of the objective object, processed and understood, and finally used for actual detection, measurement and control. The biggest feature of the technology is fast speed, large amount of information and many functions.

Visual navigation is an important autonomous navigation method. Sensors such as optoelectronics, infrared and waterproof laser pointer are assembled to complete the work. If it is greatly affected by light, the visual navigation scheme is better than the laser radar scheme in the daytime, as long as it is not in direct sunlight, but the visual navigation scheme may become a dice at night, so for the robot enterprise, It is still not a solution to replace laser radar navigation. Moreover, the information provided by the visual navigation scheme is not direct, and it is necessary to obtain the required information through sparse means such as feature extraction, thus bringing a large amount of calculation, large storage capacity and large network transmission burden. However, for large commercial robots, some overly complex sites rely on the lidar navigation scheme to solve the problem. Only by combining the visual navigation scheme can it be more stable. Therefore, for mainstream robotics companies, large-scale commercial robot navigation solutions basically adopt Lidar navigation scheme + visual navigation scheme. Only this multi-sensor fusion solution can cover robot navigation applications in various scenarios. Although the current application of visual navigation solutions is unstable, in the field of large commercial robots, visual navigation solutions are gradually becoming an indispensable auxiliary solution.

Lidar is a radar system, an active sensor, and the data formed is in the form of a point cloud. Its working spectrum is between infrared and ultraviolet, consisting of the main transmitter, receiver, measurement control and power supply. The working principle is as follows: firstly, a 488nm laser pointer beam is emitted to the target to be measured, and then the time of the reflected or scattered signal reaching the transmitter, the strength of the signal and the frequency change are measured, thereby determining the distance, the moving speed and the orientation of the measured object. The role of the laser radar is to accurately measure the position (distance and angle), shape (size) and state (speed, attitude) of the target, so as to achieve the purpose of detecting, identifying and tracking the target. In the field of robotics, it calculates the relative distance between the target and itself based on the return time of the laser after encountering the obstacle. The laser beam can accurately measure the relative distance between the contour edge of the object in the field of view and the device. These contour information form a so-called point cloud and draw a 3D environment map. For example, Joyac's lidar accuracy has reached sub-millimeter levels, helping robots to provide services.

Lidar advantages allow for extremely high angle, range and speed resolution. Lidar is highly resistant to active interference and is suitable for use in increasingly complex and intense information warfare environments. The structure of the military laser pointer radar is relatively simple, small in size and light in weight. Easy to maintain, easy to operate, and low in price.

Lidar also has its drawbacks. First of all, it is very affected by weather and air during work. The atmospheric circulation also causes the laser beam to be distorted and shaken, which directly affects the measurement accuracy of the laser radar. Secondly, because the laser radar's beam is extremely narrow, it is very difficult to search for targets in space, directly affecting the interception probability and detection efficiency of non-cooperative targets, and can only search and capture targets in a small range. Therefore, the laser radar is less directly and directly Used in battlefields for target detection and search.

These two positioning systems have begun to be applied in many fields such as intelligent robots and driverless driving. The future is also expected. As the current intelligent robot application, the usb laser pointer radar navigation maturity and penetration rate is higher. Today's commercial robots are relatively uncomplicated in terms of tasks. Lidar navigation can meet the development needs. However, in the long run, AI visual navigation positioning has a lot of room for development. Compared to lidar positioning, it can be visualized and combined with artificial intelligence to better calculate data. Let its "brains" continue to enrich the face of more complex environments.

The relationship between the two navigation systems is complementary. If the two can be well integrated, there must be an effect of one plus one greater than two. It should be based on the situation in different fields to make the two better cooperate. Nowadays, many manufacturers put things that like some conceptualization into the advertisement and hit the edge ball. Win the attention of everyone. But it is hard to say if the function of the facts can be achieved. I hope that you do not blindly believe in some advertising gimmicks. Find the product features you need and spend your money.