scholarly journals 3D MODELS OF THE QH31, QH32 AND QH33 TOMBS IN QUBBET EL HAWA (ASWAN, EGYPT)

Author(s):  
A. T. Mozas-Calvache ◽  
J. L. Pérez-García ◽  
J. M. Gómez-López ◽  
J. L. Martínez de Dios ◽  
A. Jiménez-Serrano

Abstract. This paper describes the methodology employed to obtain 3D models of three funerary complexes (QH31, QH32 and QH33) of the Necropolis of Qubbet el Hawa (Aswan, Egypt) and the main results obtained. These rock-cut tombs are adjacent structures defined by complex geometries such as chambers, corridors and vertical shafts. The main goal of this study was to discover the spatial relationships between them and obtain a complete 3D model. In addition, some models with realistic textures of the burial chambers were demanded in order to analyse archaeological, architectural and geological aspects. The methodology was based on the use of Terrestrial Laser Scanning and Close Range Photogrammetry. In general, both techniques were developed in parallel for each tomb. Some elements presented difficulties because of their reduced dimensions, the presence of vertical falls, some objects stored in the tombs that generated occlusions of some walls, coincidence of other workers, poor illumination conditions, etc. The results included three complete 3D models obtained without texture and some parts of interest obtained with real textures. All models were merged into a global 3D model. The information extracted from this product has helped architects and archaeologists to contrast their premises about the spatial behaviour of the tombs. The results have also allowed the obtaining of the first 3D documentation of these tombs under the same reference system, allowing them to be studied completely. This information is very important for documentation purposes but also to understand the spatial behaviour of these structures and the excavation processes developed by ancient Egyptians 4000 years ago.


Sensors ◽  
2020 ◽  
Vol 20 (8) ◽  
pp. 2355
Author(s):  
Paula Redweik ◽  
José Juan de Sanjosé Blasco ◽  
Manuel Sánchez-Fernández ◽  
Alan D. Atkinson ◽  
Luís Francisco Martínez Corrales

The Tower of Belém, an early 16th century defense tower located at the mouth of the Tagus river, is the iconic symbol of Lisbon. It belongs to the Belém complex, classified since 1983 as a World Heritage Site by the UNESCO, and it is the second most visited monument in Portugal. On November 1st, 1755, there was a heavy earthquake in Lisbon followed by a tsunami, causing between 60,000 and 100,000 deaths. There is a possibility of a repetition of such a catastrophe, which could bring about the collapse of the structure. This was the reasoning behind the decision to evaluate the Tower of Belém by means of surveys using Terrestrial Laser Scanning and photogrammetry. Until now, there was no high-resolution 3D model of the interior and exterior of the tower. A complete 3D documentation of the state of the Tower was achieved with a cloud of more than 6,200 million 3D points in the ETRS89 PT-TM06 coordinate system. Additionally, measurements were made using a hyperspectral camera and a spectroradiometer to characterize the stone material used in the Tower. The result is a digital 3D representation of the Tower of Belém, and the identification of the quarries that may have been used to extract its stone. The work carried out combines geometrical and material analysis. The methods used may constitute a guide when documenting and intervening in similar heritage elements. Finally, the information contained therein will allow an eventual reconstruction of the Tower in the case of another catastrophe.



2020 ◽  
Vol 8 (3) ◽  
pp. 143-150
Author(s):  
Haqul Baramsyah ◽  
Less Rich

The digital single lens reflex (DSLR) cameras have been widely accepted to use in slope face photogrammetry rather than the expensive metric camera used for aerial photogrammetry. 3D models generated from digital photogrammetry can approach those generated from terrestrial laser scanning in term of scale and level of detail. It is cost effective and has equipment portability. This paper presents and discusses the applicability of close-range digital photogrammetry to produce 3D models of rock slope faces. Five experiments of image capturing method were conducted to capture the photographs as the input data for processing. As a consideration, the appropriate baseline lengths to capture the slope face to get better result are around 1/6 to 1/8 of target distance.  A fine quality of 3D model from data processing is obtained using strip method and convergent method with 80% overlapping in each photograph. A random camera positions with different distances from the slope face can also generate a good 3D model, however the entire target should be captured in each photograph. The accuracy of the models is generated by comparing the 3D models produced from photogrammetry with the 3D data obtained from laser scanner. The accuracy of 3D models is quite satisfactory with the mean error range from 0.008 to 0.018 m.



Author(s):  
F. Menna ◽  
E. Nocerino ◽  
F. Remondino ◽  
M. Dellepiane ◽  
M. Callieri ◽  
...  

Despite being perceived as interchangeable when properly applied, close-range photogrammetry and range imaging have both their pros and limitations that can be overcome using suitable procedures. Even if the two techniques have been frequently cross-compared, critical analysis discussing all sub-phases of a complex digitization project are quite rare. Comparisons taking into account the digitization of a cultural masterpiece, such as the Etruscan Sarcophagus of the Spouses (Figure 1) discussed in this paper, are even less common. The final 3D model of the Sarcophagus shows impressive spatial and texture resolution, in the order of tenths of millimetre for both digitization techniques, making it a large 3D digital model even though the physical size of the artwork is quite limited. The paper presents the survey of the Sarcophagus, a late 6th century BC Etruscan anthropoid Sarcophagus. Photogrammetry and laser scanning were used for its 3D digitization in two different times only few days apart from each other. The very short time available for the digitization was a crucial constraint for the surveying operations (due to constraints imposed us by the museum curators). Despite very high-resolution and detailed 3D models have been produced, a metric comparison between the two models shows intrinsic limitations of each technique that should be overcome through suitable onsite metric verification procedures as well as a proper processing workflow.



Author(s):  
F. Menna ◽  
E. Nocerino ◽  
F. Remondino ◽  
M. Dellepiane ◽  
M. Callieri ◽  
...  

Despite being perceived as interchangeable when properly applied, close-range photogrammetry and range imaging have both their pros and limitations that can be overcome using suitable procedures. Even if the two techniques have been frequently cross-compared, critical analysis discussing all sub-phases of a complex digitization project are quite rare. Comparisons taking into account the digitization of a cultural masterpiece, such as the Etruscan Sarcophagus of the Spouses (Figure 1) discussed in this paper, are even less common. The final 3D model of the Sarcophagus shows impressive spatial and texture resolution, in the order of tenths of millimetre for both digitization techniques, making it a large 3D digital model even though the physical size of the artwork is quite limited. The paper presents the survey of the Sarcophagus, a late 6th century BC Etruscan anthropoid Sarcophagus. Photogrammetry and laser scanning were used for its 3D digitization in two different times only few days apart from each other. The very short time available for the digitization was a crucial constraint for the surveying operations (due to constraints imposed us by the museum curators). Despite very high-resolution and detailed 3D models have been produced, a metric comparison between the two models shows intrinsic limitations of each technique that should be overcome through suitable onsite metric verification procedures as well as a proper processing workflow.



Author(s):  
L. Zhang ◽  
F. Wang ◽  
X. Cheng ◽  
C. Li ◽  
H. Lin ◽  
...  

Abstract. 3D documentation and visualization of cultural heritage has a great significance in preserving the memories and history, and supports cultural tourism. It is of great importance to study the 3D reconstruction of cultural relics and historic sites. Preservation, visualization of valuable cultural heritage has always been a difficult challenge. With the developments of photogrammetry, terrestrial laser scanning, 3D models were able to obtained quickly and accurately. In this paper we present the survey and 3D modelling of an ancient temple, Banteay Srei, situated in Angkor, which has long been admired as a “Precious Gem” of Khmer Art for its miniature size of structures and exceptional refinement of the sculptures. The survey was performed with FARO Focus3D 330 and FARO Focus3D 120 terrestrial laser scanners, a micro unmanned aerial vehicle (UAV) (DJI Phantom 4 Pro) and a digital camera (Nikon D90). Once the acquired scans were properly merged, a 3D model was generated from the global point cloud, and plans, sections and elevations were extracted from it for restoration purposes. A short multimedia video was also created for the “Digital Banteay Srei”. In the paper we will discuss all the steps and challenges addressed to provide the 3D model of Banteay Srei Temple.



Author(s):  
H. Macher ◽  
P. Grussenmeyer ◽  
C. Kraemer ◽  
S. Guillemin

In this paper, the 3D documentation of the full structure of the Romanesque church of Dugny-sur-Meuse is discussed. In 2012 and 2013, a 3D recording project was carried out under the supervision of the Photogrammetry and Geomatics Research Group from INSA Strasbourg (France) in cooperation with C. Kraemer, archaeologist from Nancy (France). The goal of the project was on one hand to propose new solutions and tools to the archaeologists in charge of the project especially for stone by stone measurements. On the other hand, a simplified 3D model was required by the local authorities for communication purposes. To achieve these goals several techniques were applied namely GNSS measurements and accurate traverse networks, photogrammetric recordings and terrestrial laser scanning acquisitions. The various acquired data are presented in this paper. Based on these data, several deliverables are also proposed. The generation of orthoimages from plane as well as cylindrical surfaces is considered. Moreover, the workflow for the creation of a 3D simplified model is also presented.



Author(s):  
P. Grussenmeyer ◽  
A. Burens ◽  
S. Guillemin ◽  
E. Alby ◽  
F. Allegrini Simonetti ◽  
...  

The Grotta Scritta I prehistoric site is located on the west side of Cap Corse, in the territory of the municipality of Olmeta-di- Capocorso (Haute-Corse, France). This rock shelter is located on a western spur of the mountains La Serra, at 412 m height above sea level. In the regional context of a broad set of megalithic burial sites (regions Nebbiu and Agriates) and a rich insular prehistoric rock art with several engraved patterns (mainly geometric), the Grotta Scritta is the only site with painted depictions of Corsica. Around twenty parietal depictions are arranged in the upper part of the rock-shelter and takes advantage of the microtopography of the wall. Today, the Grotta Scritta is a vulnerable site, made fragile by the action of time and man. The 3D scanning of the rockshelter and paintings of the Grotta Scritta was carried out by surveyors and archaeologists from INSA Strasbourg and from UMR 5602 GEODE (Toulouse), by combining accurate terrestrial laser scanning and photogrammetry techniques. These techniques are based on a full 3D documentation without contact of the rock-shelter paintings. The paper presents the data acquisition methodology followed by an overview of data processing solutions based on both imaging and laser scanning. Several deliverables as point clouds, meshed models, textured models and orthoimages are proposed for the documentation. Beyond their usefulness in terms of valorization, communication and virtual restitution, the proposed models also provide support tools for the analysis and perception of the complexity of the volumes of the shelter (namely for the folded forms of the dome housing the paintings) as well as for the accuracy of the painted depictions recorded on the orthophotos processed from the 3D model.



2020 ◽  
Author(s):  
Christian Demmler ◽  
Marc Adams ◽  
Anne Hormes

<p>Mountainous areas bring unique challenges for surveying and natural hazard monitoring – inaccessibility, dangerous terrain, snow coverage and line-of-sight problems often make it next to impossible to perform ground-based monitoring or even to provide a good vantage point for close-range sensing (e.g. terrestrial laser scanning (TLS) or terrestrial photogrammetry). Airborne or satellite-based methods are often the only way to gain information about geodynamically active sites. Here, structure-from-motion (SfM) photogrammetry from unmanned aerial vehicle (UAV) imagery in particular can provide an inexpensive and easily implemented monitoring option. The Vigilans research project attempts to evaluate the feasibility of UAV-photogrammetry against more established surveying methods (e.g. in situ data from extensometers or total stations).</p><p>Our study site Marzellkamm is located in the Central Ötztal Alps of Western Austria. The active rock slope deformation we are monitoring in Vigilans lies at 2450-2850 m asl. on a SE-facing slope. Annual displacement rates of up to 1.5 m/year in the early 2010’s triggered monitoring and research interest. Due to the remote location, mitigation methods were not implemented, but a hiking trails was relocated. Orthoimage photogrammetry and ground-based monitoring instrumentation (extensometers, terrestrial laser scanning, total station measurements combined with GNSS and geodetic surveys) collected data 1971-2019.</p><p>In the last years, movement along the slope has slowed down considerably. The rather slow current movements provide a valuable challenge for detection, with rates of <0.05 m/year occurring in the more stable upper sections, while the NW section in particular still shows pronounced movement of up to 0.3 m/year. For this reason, Marzellkamm provides excellent evaluation for new methods such as UAV-SfM.</p><p>In three separate missions between summer 2018 to fall of 2019, UAV-SfM 3D-models of the site were created for displacement rate evaluations; it is planned to continue this monitoring for a total of three years as part of the Vigilans project. Photogrammetric missions were performed in conjunction with total station measurements of more than 30 ground control points.</p><p>The required level of precision is becoming achievable and affordable with new RTK/PPK-equipped (Real-Time-Kinematics/Post-Processed Kinematics) UAVs. However, evaluating the resulting 3D-- model in terms of movement rates remains non-trivial. The most common algorithm for change detection in point clouds, M3C2, is not well-suited to detect a laterally moving surface as a whole, as it detects changes along the normal orientation of a surface (such as subsidence). Therefore, the point cloud needs to be very selectively reduced, requiring complex filtering operations and expert input as well as expensive software packages.</p><p>This contribution will present a workflow to simplify such evaluation, based on 2.5D (DEM-based) algorithms such as IMCORR and DoD (Difference-of-DEMs), in comparison with the more complex 3D-pointcloud based processing. The presented workflow is based on Agisoft Metashape and Open-Source software tools QGIS and Saga GIS. It aims to streamline UAV-based surveying work, 3D-model generation and simplified change detection into a repeatable and easily automatable framework. Special emphasis will be put on estimating the quality of the recorded data.</p>



2018 ◽  
Vol 49 ◽  
pp. 00067 ◽  
Author(s):  
Paulina Lewińska ◽  
Dominik Sowiński ◽  
Stanisław Szombara

The purpose of this project is to determine a fast way of calculating the volume and distribution of snow mantle, which is located in wide terrain concavities in mountain areas. Our study area was so-called Szrenicki Cirque (Kocioł Szrenicki), which is the nival recess, located in Karkonosze Mountains, Poland. We analyzed modern technologies, that are designed to generate 3D-models: terrain laser scanning and close-range photogrammetry (including structure-from-motion technique). There were two major reasons for our research. First, analyzing if a structure-frommotion based software is capable of creating a 3D model of snow cover since potential tie points for adjoin pictures are scarce. The second was to establish the quality and accuracy of this model in relation to potentially more accurate terrestrial laser scanning results. An important issue was also is to estimate the fastest, simplest and least expensive methodology that can be implemented as a daily task of Karkonosze National Park workers. A proper, fast, safe and accurate method of calculating the snow cover volume would incise the safety and avalanche risk evaluation in the vicinity of Karkonosze Mountains. In addition, the developed method can be used to monitor the risk of local spring floods.



Author(s):  
D. Einaudi ◽  
A. Spreafico ◽  
F. Chiabrando ◽  
C. Della Coletta

Abstract. Rebuilding the past of cultural heritage through digitization, archiving and visualization by means of digital technology is becoming an emerging issue to ensure the transmission of physical and digital documentation to future generations as evidence of culture, but also to enable present generation to enlarge, facilitate and cross relate data and information in new ways. In this global effort, the digital 3D documentation of no longer existing cultural heritage can be essential for the understanding of past events and nowadays, various digital techniques and tools are developing for multiple purposes.In the present research the entire workflow, starting from archive documentation collection and digitization to the 3D models metrically controlled creation and online sharing, is considered. The technical issues to obtain a detail 3D model are examined stressing limits and potentiality of 3D reconstruction of disappeared heritage and its visualization exploiting three complexes belonging to 1911 Turin World’s Fair.



Sign in / Sign up

Export Citation Format

Share Document