A pseudo-3D ball lattice artifact and method for evaluating the metrological performance of structured-light 3D scanners

Evaluation of the Metrological Performance of a Handheld 3D Laser Scanner Using a Pseudo-3D Ball-Lattice Artifact

“…The original procedure for evaluating the metrological performance of a 3D scanner using the pseudo-3D artifact [ 13 ] focused on a single-scan scenario for structured-light scanners. Here, it will be expanded to several tests for a number of acquisition parameters, in order to identify the best practices to use the artifact for characterization and validation of handheld laser scanners.…”

“…The two artifacts of the standard (i.e., ball-bar and flat plate) provide information on the abilities of the scanner in measuring form, size, and distance inside its measuring volume. As discussed by Ghandali et al [ 13 ], the whole measuring volume cannot be comprehensively and systematically evaluated when using the standard’s recommendations, because both the ball-bar and the flat plate are scanned in a limited number of positions and orientations, while the user needs to systematically characterize the scanner’s performance in its entire measurement volume. Hence, there is a need for both adapted artifacts and new procedures to better characterize 3D scanners.…”

“…Ghandali et al [ 13 ] extended the idea of using a CMM-calibrated ball-plate and proposed a pseudo-3D ball-lattice artifact ( Figure 2 ) and a novel data-analysis method for evaluating the metrological performance of structured-light 3D scanners based on the calibrated reference values of the artifact. By combining calibrated spheres located in a pseudo-3D space, errors in measuring center-to-center distances, diameters, and forms of the spheres can be computed without the need for the registration of the scan-coordinate frame onto that of the CMM reference data.…”

Temperature Compensation Method for Raster Projectors Used in 3D Structured Light Scanners

“…Consumers require scanners that carry out metrologically correct measurements. Their measurement uncertainty can be described by a dedicated parameter [ 3 , 6 , 8 , 9 , 10 , 11 , 12 , 13 ] called the Maximum Permissible Error ( ) [ 6 , 9 , 10 , 11 , 14 ]; methods for its calculation have been described in the ISO 10360-8 [ 14 ] standard and the VDI/VDE2634 [ 10 ] recommendations. The error can be determined using dedicated validation artefacts.…”

“…The error can be determined using dedicated validation artefacts. Scanner calibration and its metrological validation (which involves the estimation of ) is performed in a laboratory using a stabilized environment (i.e., constant temperature, low and constant humidity, no vibrations, and no external light sources) [ 3 , 6 , 9 , 10 , 12 , 13 , 14 , 15 ]. Further measurements are often performed outside the laboratory, where the environmental conditions can vary.…”