Precision Tests of Geodetic Centring Equipment

The paper introduces testing procedures of several different geodetic centring devices performed mostly at the laboratory of the Research Institute of Geodesy, Topography and Cartography. Functional construction characteristics of a spherically mounted retroreflector Leica RRR 1.5’’, rotatable carriers Sokkia AP41 and Leica GZR3 and 12 different geodetic tribraches were examined. Further, a centring displacement instrument developed at the Czech Technical University in Prague, Faculty of Civil Engineering, Department of Special Geodesy, is evaluated in both laboratory and field conditions. For all tests, laser tracker Leica AT401 with a 5 μm standard uncertainty of absolute distance measurement, was employed