Vol. 10, No. 1, 1-8, 2011

Abstract
The aim of this research is to determine an accuracy assessment of a digital terrain model (DTM), derived from airborne laser scanning (Light Detection and Ranging or Lidar). Samples of this Lidar DTM with a resolution of 50 cm of the Mount Kemmel (Kemmelberg) in Belgium are compared with manually measured points using both Real Time Kinematic Global Navigation Satellite System (RTK GNSS) and total station. Airborne laserscanning is a well-known technique to acquire relatively accurate points in a very short timeframe over a large area. The Flemish Agency for Geographic Information (AGIV) provides statewide digital elevation models based on this technique. Although the resolution of the model of the Mount Kemmel (50 cm) is ten times higher than the standard models of the Agency (5 m), the same accuracy criteria are taken into account in this research, i.e. 20 cm for meadows, where the test sites are located. The proposed methodology consists of a comparison of this DTM with manually measured control points using RTK GNSS and total station. Since the last measurement techniques have a higher theoretical accuracy, it can be tested if the criterion of 20 cm are fulfilled and if Lidar datasets will be subsidiary with manually measured terrain points for these meadows, using a two sided t-test. The relation between these errors and the local slope of the topography are investigated as well. A full elaboration, describing the difference between and substitution of the Lidar dataset and the total station dataset, is given in this paper.

ISSN 1729-3782