A Test of Height Transfer Using Vertical Deflection Measurements by the Digital Zenith Camera VESTA

Abstract

A test application of a height transfer method employing quasi-geoid undulation extrapolation using vertical deflection (VD) measurements obtained by the digital zenith camera VESTA (VErtical by STArs) is described. This method in combination with ellipsoidal height measurements by global navigation satellite system (GNSS) may provide a cheaper and more convenient alternative to classical geometrical leveling, particularly for long distances and/or when natural or administrative obstacles are present. VD measurements were taken along a 4.5-km traverse of the first-order leveling points located at both ends and in the middle, with GNSS measurements taken at the first-order leveling points. The height transfer results were then compared to the existing network data from the national database. The agreement between the height transfer results and the leveling network data was within the expected deviations. Possible error sources were evaluated, and requirements for VD measurement point selection were formulated.