Hokuyo UTM-30LX and Hokuyo UTM-30LX-EW are the most widely used LiDARs used for SLAM problem solving for mobile autonomous robots.
With a full range of 30m both laserscanners provide an accuracy of 10mm.
Both UTM-30LX and UTM-30LX-EW have a scan angle of 270 degrees divided into 1080 measurement steps.
Reflectivity considerations of UTM-30LX and UTM-30LX-EW Laserscanner:
The reflectivity of the LiDARs depend a lot on the surfaces. We will consider the reflectivity of the hokuyo UTM series LiDAR from the distance of 1m. The surfaces we are considering are
a polished metal plate (mirror finish),
a black painted metal plate and
a plate covered with a black sheet of paper.
Each surface was scanned 3000 times.
After scanning the surfaces over 3000 times we conclude that the distance measurement is more accurate for surfaces which are less reflective.
The reflectivity also depends on the perpendicularity. The intensity of laser beam for the reflective surfaces perpendicular to the laserscanners is higher, which gives a slightly different reading of distance measurement. The error however is less than 1%.
Spatial orientation of the LiDARs on mobile robots.
The effect of sensors installation and orientation is very crucial as the LiDAR is mounted on a mobile robot.
The robot while moving encounters obstacles to either avoid or run over them or small steps. The wind may also drift the position of the robot. The robot orientation may sway in its pitch and roll angles.
Experiments on robotic platforms have shown that the sensor spatial orientation does not have a significant effect on the precision of measurements
Importance of distance
The effect of the distance between the target and the LIDAR is very important since it determines the position and orientation of the LIDAR on the robot hence where on the conductors the LIDAR will point, i.e., how far in front the robot the LIDAR should scan.
The UTMs provide an accuracy of 10mm which as per our experience has conformed to the range specifications of the laserscanner