The Possibility of Using Images Obtained From the Uas in Cadastral Works

Abstract

ABSTRACT:Updating the cadastre requires much work carried out by surveying companies in countries that have still not solved the problem of updating the cadastral data. In terms of the required precision, these works are among the most accurate. This raises the question: to what extent may modern digital photogrammetric methods be useful in this process? The capabilities of photogrammetry have increased significantly after the introduction of digital aerial cameras and digital technologies. For the registration of cadastral objects, i.e., land parcels' boundaries and the outlines of buildings, very high-resolution aerial photographs can be used. The paper relates an attempt to use an alternative source of data for this task -the development of images acquired from UAS platforms. Multivariate mapping of cadastral parcels was implemented to determine the scope of the suitability of low altitude photos for the cadastre. In this study, images obtained from UAS with the GSD of 3 cm were collected for an area of a few square kilometres. Bundle adjustment of these data was processed with sub-pixel accuracy. This led to photogrammetric measurements being carried out and the provision of an orthophotomap (orthogonalized with a digital surface model from dense image matching of UAS images). Geometric data related to buildings were collected with two methods: stereoscopic and multi-photo measurements. Data related to parcels' boundaries were measured with monoplotting on an orthophotomap from low-altitude images. As reference field surveying data were used. The paper shows the potential and limits of the use of UAS in a process of updating cadastral data. It also gives recommendations when performing photogrammetric missions and presents the possible accuracy of this type of work.

High-Quality UAV-Based Orthophotos for Cadastral Mapping: Guidance for Optimal Flight Configurations

“…In the domain of land administration, UAV technology gained in importance as a promising technique that can bridge the gap between time-consuming but accurate field surveys and the fast pace of conventional aerial surveys [2,3]. Various publications tested UAV-based workflows for cadastral applications, covering formal cadastral systems such as in Albania [4] Poland [5], The Netherlands [6], or Switzerland [7] as well as less formal systems in Namibia [8], Kenya [9], or Rwanda [10]. Findings examine vast opportunities, especially with the additional information of textured 3D models and high-resolution orthophotos that ease public participation in boundary delineation [4,8,11].…”

Verification of the Geometrical Representation of Buildings in Cadastre Using UAV Photogrammetry

“…The planned 80/60 overlap guaranteed that each potentially measured point could be observed in at least 6 images. The results that were obtained in this photogrammetric processing are described in [8]. The RMS for control points was calculated to be 0.018 m, 0.018 m and 0.013 m for X, Y and Z respectively, and during verification of the check points, the RMS errors were 0.043 m, 0.047 m and 0.074 m respectively, constituting a slightly lower degree of accuracy.…”

“…Remote sensing has started to be used in commercial and scientific research, such as digital mapping, monitoring of landslides and disasters, as well as monitoring and planning of agricultural land [7]. However, recently UAV solutions have been able to achieve centimetre-level accuracy, comparable to direct surveying methods, which is the reason for using drones in cadastral issues related to parcel boundaries [8][9][10][11][12][13][14][15][16][17][18]. All UAV regulations have the common goal of minimizing the risks to other airspace users and to both people and property on the ground.…”

Extraction of Visible Boundaries for Cadastral Mapping Based on UAV Imagery

“…Proposed cadastral surveying techniques are mostly indirect ones rather than ground-based. Ground-based techniques are often argued as being time-consuming and labor intensive [1,5,8].Emerging tools are mapping techniques based on remote sensing data, in particular, data acquired with sensors on Unmanned Aerial Vehicles (UAVs) [9][10][11][12][13][14][15][16][17][18]. Cadastral maps are usually defined as a spatial representation of recorded land plot boundaries or other spatial units that the land rights concern [19].…”

“…In developing countries, UAV-based cadastral mapping usually serves as a tool for the creation of a formal cadastral system [11][12][13]. In developed countries, the case studies focus on the assessment of UAVs' data positional accuracy estimation and its conformity with local positional accuracy requirements aiming to use the UAV data for updating existing cadastral maps [14][15][16][17][18]. Here, updating in most cases refers to the comparison of two cadastral maps-one representing the database state, the other recently acquired data.…”