Lidar has done a lot in every segment, especially in the field of robots and unmanned driving. As far as single-line Lidar is concerned, it is committed to solving the problem of autonomous positioning and navigation of robots. As an important indicator for judging the performance of lidar, what important parameters are worth paying attention to when purchasing?
Ranging distance
The main function of lidar is distance measurement, which refers to the farthest distance the sensor can detect an object. The maximum distance (range) measured is naturally its core indicator. Most lidars directly use measurement distance as their main indicator.
scanning frequency
The higher scanning frequency can ensure that the robot with the lidar can achieve faster movement and ensure the quality of map construction. However, increasing the scanning frequency is not just a matter of speeding up the rotation of the internal scanning motor of the lidar. Correspondingly, it is necessary to increase the ranging sampling rate. Otherwise, when the sampling frequency is fixed, the faster scanning speed will only reduce the angular resolution.
Measurement resolution
For lidar, the measurement resolution is more challenging for triangulation ranging radar. Due to the measurement principle, although high ranging resolution can be achieved within 10 meters, the resolution will also vary. As the detection object distance increases, it drops sharply. Therefore, in order to achieve longer-distance detection, it is not only as simple as increasing the laser power, but also the essential improvement of the ranging core. At the same time, a lot of supporting work needs to be done for reliable mass production.
Comparison of different sampling rates
measurement accuracy
Measurement accuracy refers to the true value obtained after measuring a certain amount. It is the degree of consistency with the truth. Repeatability is also called reproducibility or repeatability, which is a quantity used to express the possibility of obtaining the same result from multiple measurements.
I believe you are not unfamiliar with the several parameters listed above, but to further improve the practicability and reliability of lidar, the detection rate of dark objects and the anti-interference ability of ambient light are also the focus of attention.
Detection rate of dark objects
In practical applications of lidar, dark objects such as furniture and dark wallpapers are often encountered. Since dark objects absorb most of the light energy, it is obviously unrealistic to make lidar have the same detection power for dark objects and white objects. This is especially true for the triangular ranging principle radar with machine vision as the core. .
Nowadays, the detection ability of dark objects is also regarded as the key direction of lidar research. Silan Technology's lidar can also achieve a detection distance of more than 10 meters for black objects with a reflectivity of less than 10%. Under normal circumstances The model claims to have a lidar above 10 meters, which can at least achieve effective detection of dark objects above 6 meters, and Silan's lidar can effectively detect even if it is below 10 meters.
Ambient light anti-interference ability
In addition to the ability to detect dark objects, lidar is also susceptible to light in actual work, such as direct sunlight outside the window and artificial indoor lights, which will affect the lidar sensor. It is easy to cause noise in the lidar, and at the same time, it may also cause the effective measurement range of the radar to be shortened or the distance measurement is completely impossible. Therefore, it is necessary to have more excellent processing algorithms and optical adjustments to distinguish between ambient light and laser signals.
Limited by the principle problem, the impact is more serious for the lidar that adopts the triangular ranging principle, but this is not the case for the RPLIDAR lidar of Silan Technology. Since the first generation of RPLIDAR A1, Silan Technology has attached great importance to ambient light. Anti-jamming capability. At present, its third-generation lidar RPLDIAR A3 can support both enhanced and outdoor modes. In enhanced mode, the range and sampling frequency of RPLIDAR A3 can reach the maximum value. In outdoor mode, RPLIDAR A3 has a more reliable anti-interference ability against sunlight, and at the same time, it has a more stable ranging performance when detecting black-and-white, long-distance, and direct-light objects.
To judge the performance of lidar, the parameter index is important, but it is not blindly pursuing the parameter value. It is mainly based on product demand. The radar that suits your product is the best radar.