Methods for Geometric Accuracy Investigations of Terrestrial Laser Scanning Systems

Currently the second, or for some manufacturers even the third, generation of terrestrial laser scanning systems is available on the market. Although the new generation of terrestrial 3D laser scanning systems offer several new (geodetic) features and better performance, it is still essential to test the accuracy behaviour of the new systems for optimised use in each application. As a continuation of previously published investigations the Department Geomatics of the HafenCity University Hamburg (HCU Hamburg) carried out comparative investigations into the accuracy behaviour of the new generation of terrestrial laser scanning systems (Trimble GX, Leica ScanStation I and 2, and Riegl LMS420i using time-of-flight method and Leica HDS6000, Z+F IMAGER 5006, and Faro LS880 HE using phase difference method). The results of the following tests are presented and discussed in this paper: test field for 3D accuracy evaluation of laser scanning systems, accuracy tests of distance measurements in comparison with reference distances, accuracy tests of inclination compensation, and influence of the laser beam's angle of incidence on 3D accuracy.