Cadastral surveys using terrestrial laser scanning - accuracy and economy

Abstract

Due to the wide range of possible applications, terrestrial laser scanning (TLS) has long since found its way into monument protection and construction. The advantage of this technology is the resulting 3D image of the surroundings including all visible objects as a 3D point cloud. At the office, all necessary information can be derived from the data set using specialized software. In order to test the suitability of TLS to create partition plans according to the Ordinance on Cadastral Surveying (VermV), a case study was conducted using both, a total station and a TLS. Both recordings were evaluated and compared for accuracy, cost-effectiveness, and legality. The accuracy of a TLS mainly depends on the care taken in the evaluation. Deviations occur if geometries are misinterpreted, however, such mistakes can be corrected in the office. From an economic point of view, the TLS requires 14% less total working time. The workload is shifted from the field to the office, with a 68% reduction in field work time. This leads to a reduction in costs and less disruption in the surveyed area. The use of a TLS is legally covered by the VermV. A major advantage of the technology is the recording of the entire environment suited for documentation, preservation of evidence, and added value for planners. However, the decision on the use of a TLS needs to be done case-based.

Terestrično lasersko skeniranje (TLS) je zaradi široke uporabnosti že dolgo prisotno tudi na področjih gradnje objektov in spomeniškega varstva. Prednost te tehnologije je zajem 3D-posnetka okolice, ki vključuje vse vidne predmete v obliki 3D oblaka točk. Iz podatkovnega niza lahko z ustrezno programsko opremo pridobimo vse potrebne informacije v pisarni. Da bi preizkusili primernost TLS za izdelavo katastrskih načrtov v skladu z avstrijsko uredbo o katastrski izmeri (VermV), smo izvedli študijo primera z uporabo tahimetra in TLS. Oba posnetka smo ovrednotili in primerjali glede natančnosti, stroškovne učinkovitosti in zakonitosti. Natančnost TLS je odvisna predvsem od skrbnosti analize podatkov. Odstopanja se pojavijo, če napačno interpretiramo geometrijo, napake je mogoče popraviti v pisarni. Z ekonomskega vidika TLS zahteva 14 % manj skupnega delovnega časa, terenskego delo se zmanjša za 68 %, posledica česar je znižanje stroškov in zmanjšanje motenj na območju izmere. Avstrijska uredba VermV legalizira uporabo sistema TLS za katastrsko izmero.Glavna prednost tehnologije je snemanje celotnega okolja, posnetki pa so primerni za dokumentiranje, ohranjanje dokazov in pomenijo dodano vrednost za načrtovalce. Odločitev o uporabi TLS je treba sprejeti za vsak primer posebej.