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EN
The study tested the capabilities of the Apple iPhone 13 Pro device using two measurement techniques, LiDAR (Light Detection and Ranging) and SfM (Structure from Motion), in a cave environment by measuring scallops in Mylna Cave in Western Tatra Mountains. The tested device provides an interesting and inexpensive alternative for cave research using TLS (Terrestrial Land Scanner) type scanners or more expensive MLS (Mobile Laser Scanning) type scanners. The study used a dedicated 3D Scanner App™ application to create two terrain models: LiDAR and SfM. A comparative analysis of the models shows that the SfM model is characterised by greater detail. The results obtained for this model indicate that the scallops measured in Wielki Chodnik passage of Mylna Cave belong to at least two different generations of forms. In the LiDAR method case, the obtained models’ resolution was not precise enough to identify small (<3 cm) scallops. For three LiDAR models, the average length of scallops was 10.32 cm; for three SfM models, it was 5.16 cm. The length of scallops obtained from models allowed for calculating paleoflow velocity and, thus, the flow rate. The average velocity value for LiDAR models was 28.98 cm s−1, and for SfM models – 48.10 cm s−1 and the average flow rate obtained from SfM data was 1.93 m³ s−1. It corresponds well with the today-observed Kościeliski Potok flow rate of 1.7 m³ s−1 according to the 1966–2000 period (Baścik et al. 2014). On the contrary, the average paleoflow rate obtained from the LiDAR model, which is 0.94 m³ s−1, does not match the contemporary flow rate. Based on the asymmetry of scallops, the paleoflow direction was determined. It is consistent with the current direction of the Kościeliski Potok flow. The spatial imaging techniques used with iPhone 13 Pro differ regarding the DEM creation method and model details. It is influenced by parameters related to lighting, distance, scanned surface character and microclimatic conditions of the cave.
EN
This paper presents the results of a study to assess the feasibility of using the Structure from Motion photogrammetric method to estimate what parts of Wołek Castle have survived from the 15th century to the present day. The photogrammetric measurements were made with a Nikon D5200 camera, and 249 mock-up images were obtained. Planimetry and altitude coordinates of the castle ruins were obtained using RTN GNSS measurements and the polar method. The measurements were made in the 2000 coordinate system in zone 6, the heights were obtained in the Kronstadt system. Two spatial models were made. The first one in the field scale was made using the ground control points measured in the terrain. The second one was made using ground control points measured on the model in the local system. The control measures were analyzed, the model compared with the actual orthophotomap, and it was estimated what part of the castle was preserved in reality.
PL
W artykule przedstawione zostały zagadnienia związane z przetwarzaniem i analizą zdjęć, pozyskanych niskobudżetowymi sensorami naziemnymi i Bezzałogowym Systemem Latającym (BSL), miejskich stanowisk archeologicznych zlokalizowanych na terenie Kutaisi w Gruzji. Przedstawiono problematykę przeprowadzania badań archeologicznych na obszarze miejskim oraz przybliżono problem braku danych źródłowych dla badanego terenu. W celu wygenerowania dokumentacji fotogrametrycznej dla stanowiska Bagrati, zdecydowano się na wykorzystanie niskobudżetowego BSL DJI Phantom 3 oraz kamery Pentax. Ze względu na jakość geometryczną i radiometryczną wykorzystywanych sensorów niezbędne było zaproponowanie rozszerzonej metodyki przetwarzania danych z BSL i zdjęć naziemnych w oprogramowaniu Agisoft PhotoScan. W tym celu wykorzystano interfejs programistyczny API (ang. Application Programming Interface), pozwalający na wykorzystanie funkcji oprogramowania niedostępnych w podstawowej wersji aplikacji oraz autorski skrypt stworzony w MatLab. Zaproponowano sposób przetwarzania, filtracji, usuwania oraz wagowania obserwacji. W wyniku przeprowadzonych prac i sposobu filtracji danych poprawiono dokładność procesu aerotriangulacji o rząd wielkości w porównaniu do obserwacji surowych, jak również rozszerzono analizę statystyczną danych.
EN
In this research, the issues related to processing and analysis of the images, acquired by the low-cost terrestrial sensors and an unmanned aerial vehicle (UAV) of the archaeological sites in an urban environment placed in area of Kutaisi, Georgia, have been considered. Taking into account generation of the Bagrati site photogrammetric documentation, the low-cost UAV DJI Phantom 3 and Pentax SLR camera, were chosen. Due to the geometrical and radiometric parameters of the chosen sensors, an extended methodology of UAV and terrestrial data processing in Agisoft PhotoScan was proposed. This task solution was enabled by application programming interface API (which allowed taking advantage of software functions - not available in the basic version of the program) and additionally the script written in MatLab software by authors. The method of processing, filtrating, eliminating and weighting of the measurement observations in the bundle adjustment process was proposed . As a result of performed works, the accuracy of the results of the bundle adjustment, increased significantly in comparison to the raw data. Furthermore, statistical data analysis had been expanded.
EN
Projection of a complicated geometry of industrial objects is the complex issue, which requires properly planned and prepared measurements. Such objects must be accurately inventoried, but their complicated nature often makes the access and the visibility of their entire surface very difficult. Documentation of measurements is often prepared in the form of sketches, plans or maps, which are amended with photographic documentation. The objective of this paper is to test the possibilities to apply laser scanning and the network of digital images for inventory and monitoring of technical conditions of industrial objects. Processing of a precise documentation acquired basing on terrestrial laser scanning data or dense points clouds generated from digital images still causes many difficulties and problems. Although data processing algorithms have been intensively developed with respect to generation of high resolution orthoimages or precise vector drawings, the existing problems are still connected with limitations related to imperfections of both techniques of measurements.
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