Description

The main aim of the project was to explore the possibilities of using remote sensing for the cadastral geospatial data acquisition. The project was focused on the use of optical sensors on Unmanned Aerial Vehicles – UAV for photogrammetric geospatial data acquisition. The focus of the project was on the optimization of the photogrammetric data acquisition for cadastral mapping. Photogrammetric cadastral data acquisition is not a novelty in the land cadastre, as the first projects in Europe and at the wider international level appeared already in the 1950s. In particular, those projects should be understood as a consequence of the technological development in the field of optical geospatial acquisition of spatial data by airplanes. Recently, the main challenge in the field of photogrammetric cadastral mapping has been in the development of new platforms and technologies for geospatial data acquisition from the air, remote-controlled systems for geospatial data acquisition, known also as Unmanned Aerial Systems – UAS. The unexplored has been the field of marking of ground control points and cadastral points in the field, which would allow optimization of the processing and interpretation of the acquired geospatial data.

Project goals

The main objective of the project was to examine and evaluate the different ways of marking of ground control points and cadastral points for the purpose of UAV-cadastral mapping. The various ways of ground control and cadastral points’ marking were examined mainly from the aspects of:

• The possibility (semi)automatic identification of targets (signals) for image processing of acquired geospatial data,
• The positional accuracy of point clouds and orthophoto, and
• The positional accuracy of cadastral points in the national geodetic reference system D96/TM.

The results of testing the different methods of marking ground control points and cadastral points in study areas with a defined methodology for the quality assessment was the basis for formulating proposals for an UAV-based photogrammetric cadastral mapping. The recommendation includes proposals for planning and implementing UAV-based photogrammetric cadastral survey, methodological recommendations for image processing and feature extraction, including proposals for marking ground control points and cadastral points, for control measurements, and for quality assessment of the data acquired.

Project work packages

• Work Package 1 (WP1): Determination of the photogrammetric cadastral mapping using Unmanned Aerial Vehicles – UAV [M01-M08];
• Work Package 2 (WP): Testing the quality of different methods for marking ground control and cadastral points from the perspective of automatic detection of points and image measurements on a point cloud and orthophoto [M07-M18];
• Work Package 3 (WP3): Suitability assessment of the proposed photogrammetric cadastral mapping using UAVs [M19-M24];
• Work Package 4 (WP4): Making recommendations for the UAV-based photogrammetric cadastral mapping [M22-M24];
• Work Package 5 (WP5): Coordination and dissemination [M01-M24].

Results

Reviewed papers published in international journals:

• Kosmatin Fras, M., Drešček, U., Lisec, A., Grigillo, D. (2020). Analiza vplivov na kakovost izdelkov UAV fotogrametrije. Geodetski vestnik, 64 (4), 489–50. DOI: https://doi.org/10.15292/geodetski-vestnik.2020.04.489-507
• Fetai, B., Račič, M., Lisec, A. (2019). Visible Land Boundaries from UAV Imagery. Remote Sensing, 13 (11), 2077. DOI: https://doi.org/10.3390/rs13112077
• Drešček, U., Kosmatin Fras, M., Tekaevc, J., Lisec, A. (2021). Spatial ETL for 3D building modelling based on unmanned aerial vehicle data in semi-urban areas. Remote sensing, 12 (1972). DOI: https://doi.org/10.3390/rs12121972

Papers presented at symposiums:

• Grigillo, D., Petrovič, D., Kozmus Trajkovski, K., Urbančič, T., Kosmatin Fras, M. (2020). Korektna uporaba letalnikov v geodeziji. Referat na simpoziju 48. geodetski dan, Ljubljana, 17. 9. 2020. Ljubljana: Zveza geodetov Slovenije.
• Fetai, B., Tekavec, J., Kosmatin Fras, M., Lisec, A. (2021). Samodejni pristopi za analizo skladnosti mej dejanske rabe in katastrskih mej zemljišč na podlagi UAV fotografij. Referat na simpoziju 49. geodetski dan, Koper, 16. 9. 2021. Ljubljana: Zveza geodetov Slovenije.

Other presentations (in Slovene): 

• Daljinsko vodeni letalniki v zemljiškem kaatstru: https://www.fgg.uni-lj.si/daljinsko-vodeni-letalniki-v-zemljiskem-katastru/
• Predstavitev rezultatov projekta 10. 12. 2021.

Final report (in Slovene):

• Lisec, A., Kosmatin Fras, M., Grigillo, D., Čeh, M., Kozmus Trajkovski, K., Fetai, B., Drešček, U., Urbančič, T., Tekavec, J., Pavlovčič Prešeren, P., Kregar, K., Oštir, K., Drobne, S., Petrovič, D., Trobec, B. (2021). Ovrednotenje različnih načinov označitve katastrskih mejnikov za fotogrametrično izmero z letalnikom in analiza njihovega vpliva na položajno točnost oblaka točk in ortofota : ciljni raziskovalni program “CRP 2019” v letu 2019. Končno poročilo – raziskovalni projekt št. V2-1934. Ljubljana: Univerza v Ljubljani, Fakulteta za gradbeništvo in geodezijo. https://repozitorij.uni-lj.si/IzpisGradiva.php?id=133469