Investigations on the Geometric Accuracy of the NavVis VLX 2 and VLX 3 Systems for the Use in Indoor Applications

Mobile mapping technology from NavVis GmbH enables buildings and interiors to be captured quickly and accurately, creating digital twins. At HafenCity University (HCU) Hamburg, the NavVis VLX 2 and VLX 3 were used to test an interior recording system and compare it with reference data from the Z+F IMAGER 5016 terrestrial laser scanner. Geometric accuracy was analysed using two 3D test fields in the HCU Hamburg geodetic laboratory. During the investigations, the spatial distances in the 3D test fields showed an average deviation of 6 mm and a maximum deviation of 18 mm without control points, and 4 mm with a maximum deviation of 14 mm with control points. Various error simulations were performed, introducing gross errors of up to 20 cm in individual control point coordinates, some of which could be detected. When the 3D point clouds were compared with the Z+F IMAGER 5016 static terrestrial laser scanner reference, slight shifts in the point cloud were observed depending on the distance to the control points. However, these shifts were within the manufacturer's accuracy specifications and ranged from a few millimetres. The laboratory tests proved that the NavVis VLX 2 and VLX 3 are very efficient, easy-to-use indoor recording systems.