A non-standard mark‘s center recognition correctness by a 3D laser scanner

Abstract

Terrestrial laser scanners have sophisticated specialized software that makes it possible to measure three-dimensional coordinates of a huge number of points in a short period by registering vertical and horizontal angles. To determine the spatial position of the scanner and the coverage of the area of interest on one scan, special marks are placed around the scanner. These marks are used for further high-precision scan matching. The problem of the process of recognizing the center of black and white marks during field shooting, as separate from the scanning process itself, is a separate task, which has not been sufficiently studied. The purpose of the experiment is to establish the correctness dependence of the mark center recognition on its various characteristics. The technique is the experimental component and theoretical analysis of the obtained material. The experiment was carried out under the same conditions, so that the influence of the distance from the device to the mark, a change in the angle between the laser beam and the mark plane could not affect the recognition correctness of the mark center. In the course of the experiment, 8 marks were prepared with a non-standard view and size, as well as one standard black and white mark, to check the reliability of the data obtained (diameter 74.1 mm, two opposite sectors are black, and the other two are white). This experiment showed that the process of recognizing the mark center depends on the combination of the following characteristics: mark geometry, mark color, the opposite sectors of the mark.