Calculation of sphere centers based on point cloud data from a Metrological Laser Radar

The increasing demands for 3D measurement accuracy in industrial metrology and quality control highlight the performance evaluation of Metrological Laser Radars (MLRs). The fitting calculation of sphere centers plays an important role in the relative range test of MLRs. This paper addresses this challenge by investigating the 3D point could data of a sphere by a MLR. In the experiment, the sphere is scanned at seven positions to analyze the influence of cone angles on the Root Mean Square (RMS) of sphere center fitting based on the cone-cylinder method given in the ASTM E57 standard. The results validate the applicability of the ASTM E57 standard for evaluating the accuracy of MLRs, and indicate that the laser incidence angle of the MLR may have a small impact on the RMS of the point cloud of the standard sphere surface.