UAV-BASED CADASTRAL MAPPING: AN ASSESSMENT OF THE IMPACT OF FLIGHT PARAMETERS AND GROUND TRUTH MEASUREMENTS ON THE ABSOLUTE ACCURACY OF DERIVED ORTHOIMAGES

Abstract. In the domain of land administration, UAV-based orthophotos are gaining in importance as base data to support the extraction of cadastral boundaries and further visual interpretation, manual digitization, or automated feature detection procedures. However, the fact that UAV-derived geographical information can support decision-making processes that involve people’s land rights ultimately raises questions about the quality of the respective data. Especially geometric accuracy and radiometry can be negatively influenced by poor flight planning, densely populated areas, and adverse meteorological conditions. Thus, this paper takes a closer look at optimal workflows to minimize the need for ground truthing by presenting an experimental assessment of flight parameters and ground truth methods. More than 40 datasets entail the representative basis to investigate the impact on the absolute geometric accuracy of derived UAV-based orthomosaics. Results suggest that UAV data acquisition workflows can cover a wide range of data quality depending on UAV equipment, flight planning parameters and ground truthing strategies. Ultimately, this paper can help to determine the best approach to provide a high-quality data product that satisfies end user and supports the provision of reliable base data for automated or manual extraction of cadastral boundaries.