Terrestrial Digital Photogrammetry Research Articles

Побудова твердотілої моделі історичного об’єкту: на прикладі форту «Марушка Ліс»

Purpose of this work is to use terrestrial laser scanning for analysis and construction of a digital model of the fort “Marushka Lis” focusing on the process of data collection, processing, and their further use, particularly for web mapping of post-military sites. In the modern world, the preservation and restoration of historical structures is an important task that requires the application of advanced technologies. Methodology. Terrestrial laser scanning serves as an indispensable tool in this process, providing accurate and detailed spatial data. A technological scheme for creating a digital model of a historical object has been proposed. The study of historical objects using various methods of information collection was considered, namely: topographic surveying, terrestrial digital photogrammetry, terrestrial laser scanning, ground-penetrating radar studies, tachymetric surveying, GNSS. The methodology for creating a digital model of a historical object and the presented technological scheme, which includes data collection, processing of the obtained results, and output data, are described. Results. A comprehensive approach was applied to create the model, which included studying the history of the object, terrestrial laser scanning, terrestrial digital photogrammetry, and conducting geodetic measurements. A key aspect was the accurate and detailed reproduction of all architectural and structural elements of the fort. The use of software such as Leica Cyclone REGISTER 360, Autodesk ReCap, and Autodesk Revit allowed the integration of collected data into one accurate and detailed model. The sequential execution of work according to the proposed methodology enabled the creation of a digital model of the fort “Marushka Lis.” Scientific novelty and practical significance. The scientific novelty lies in the use of terrestrial laser scanning and 3D modeling for the reconstruction of a destroyed post-military object. The obtained digital model of the fort “Marushka Lis” will be used in web mapping of post-military sites in Lviv region.

Digital preservation of classical gardens at the San Su Shrine

Chinese classical gardens, an essential part of World Cultural Heritage, are well exemplified by Xishu Garden as a notable branch of this tradition. This research focuses on the San Su Shrine—a quintessential example of Xishu Garden—and explores the application of digital technologies in the commemorative research and quantitative preservation of these gardens. By integrating terrestrial laser scanning and terrestrial digital photogrammetry, we acquired quantitative data and constructed digital models to innovate upon the methodological approach to garden conservation. The innovation of this study is its analysis of Xishu Garden’s commemorative spaces through both temporal and spatial dimensions. 1) Temporally, this study examines the evolution and stratification of the garden's commemorative elements across various historical periods. 2) Spatially, it explores the interconnectedness of commemorative elements within the garden's buildings, rockery stones, water landscape and plant landscape. This dual-faceted approach yields novel insights and methods for assessing the universal value of the commemorative aspects of Xishu Garden. Moreover, it promotes the application of digital technology in the study and preservation of Xishu and other Chinese classical gardens.

Damage and restoration of historical urban walls: literature review and case of studies

Within this work, the causes of collapses and damages occurred in masonry artefacts have been evaluated to properly identify suitable monitoring and restoration methods. In this regard, a comprehensive literature review has been performed. Based on the results, the moisture has found to be a critical parameter, which affects the structural health of masonry artefacts. Diverse non-destructive methods were employed to measure the moisture and monitor the materials involved: the Infrared Thermography, the Electrical Resistivity Tomography and the Ground Penetrating Radar, the Laser Scanning and Digital Terrestrial Photogrammetry, the Global Navigation Satellite Systems, the Unilateral Nuclear Magnetic Resonance, the Laser-Induced Fluorescence technique, the Acoustic Imaging and the Acoustic Tomography, the Geographic Information System and on-site survey process as well as computer modeling of the structure with specific FEM software. Finally, the implementation of tie-beams, Fiber Reinforced Polymers layers, ventilation, draining systems, and high-quality materials are proposed as solutions for controlling the moisture effect and retrofitting.

New insights into human occupation through rock art at Khatm al Melaha archaeological site (Sharjah, United Arab Emirates)

This paper is an approach to the study and documentation of a quite large group of rock art boulders at Khatm al Melaha (Sharjah, United Arab Emirates). More than 150 decorated stone blocks, with almost 400 motifs, have been identified on a hill close to the Arabian Sea coast, highlighting its importance as a control point for communicating the coast and the hinterland. Although a domestic human occupation of the area has not yet been documented, the symbolic significance of this place is reinforced not only by rock art but also by the presence of several dry-stone tombs. Despite the limited studied area, our contribution outlines a preliminary approach to a previously very little studied territory, providing a local chrono-stylistic proposal for those figurative (humans, animals) and non-figurative (signs) engravings attending to different stylistic conventions, techniques, subject matters and varnish colour. Different digital documentation techniques (digital tracings, terrestrial and aerial photogrammetry, web mapping) have been applied in order to create an updated and accurate data corpus allowing future analysis. The ongoing research will try to find new evidence of symbolic occupation of the territory in relation to human settlements and their relationship within a wider landscape.

Digital terrestrial photogrammetry for a dense monitoring of the surficial displacements of a landslide

A new method for measuring spatially dense surface displacements of a landslide at daily intervals and over a long period of time is here presented. The method allows the evaluation of displacements based on a digital image correlation technique applied to a temporal sequence of photos, daily captured by one or more fixed cameras. In comparison to other topographical method this new procedure has a lower accuracy, but provides distributed daily measurements, spatially very dense over the entire landslide area. The multi-view configuration also allows the reconstruction and the update of the 3D surface of the landslide. This work presents some preliminary results obtained by applying this innovative technique to a complex landslide located in the municipality of Perarolo di Cadore (NE Italy), also known as Sant’Andrea landslide. The landslide is characterized by active slow movements involving detrital deposits, about 30 m thick, overlying gypsum-anhydrite rocks. Its activity is strongly correlated to both heavy and long-lasting rain events and to its particular geological conditions. Recently, the alternating phases characterized by slow movements and significant accelerations led to a progressive enlargement of the affected area. Three cameras installed on a stable slope facing the landslide allow to record the intermittent activity and the peculiar behaviour of different parts of the slope. The displacements thus obtained are also compared with those deriving from conventional techniques. Finally, the accuracy of this new method is discussed.

Rockfall Threatening Cumae Archeological Site Fruition (Phlegraean Fields Park—Naples)

Natural hazards threaten many archaeological sites in the world; therefore, susceptibility analysis is essential to reduce their impacts and support site fruition by visitors. In this paper, rockfall susceptibility analysis of the western slope of the Cumae Mount in the Cumae Archaeological Site (Phlegraean Fields, Naples), already affected by rockfall events, is described as support to a management plan for fruition and site conservation. Being the first Greek settlement in southern Italy, the site has great historical importance and offers unique historical elements such as the Cumaean Sibyl’s Cave. The analysis began with a 3D modeling of the slope through digital terrestrial photogrammetry, which forms a basis for a geomechanical analysis. Digital discontinuity measurements and cluster analysis provide data for kinematic analysis, which pointed out the planar, wedge and toppling failure potential. Subsequently, a propagation-based susceptibility analysis was completed into a GIS environment: it shows that most of the western sector of the site is susceptible to rockfall, including the access course, a segment of the Cumana Railroad and its local station. The work highlights the need for specific mitigation measures to increase visitor safety and the efficacy of filed-based digital reconstruction to support susceptibility analysis in rockfall prone areas.

Digital Terrestrial Photogrammetry to Enhance Field-Based Forest Inventory across Stand Conditions

Forest inventories in uncertain future economic and environmental conditions require the development of cost-effective measurement techniques to provide robust and accurate information on forests across regional and global scales. Digital terrestrial photogrammetry (DTP) can be used to detect and measure trees on sample plots. In this study, a method was developed which used spherical images taken strategically within plots, and under varying acquisition conditions, to derive forest inventory attributes. Using a set of 102 photos on 400 m2 circular plots achieved a mean detection rate of 72.3% and estimated diameter to an RMSE of 19.0%. This study also explored the sensitivity of detection and estimation accuracy to different field and acquisition conditions. Detection of individual trees was significantly influenced by the tree size and species (p < 0.05 in a regression analysis), while plot-level detection was influenced by size and stem density. Tree size and the distance to the camera significantly influenced the accuracy of estimated attributes. These results are comparable to those of other DTP and terrestrial laser scanning studies in similar forest types while using fewer photos and less time, demonstrating the value of cost-effective methods for DTP estimation of forest attributes.

DIGITAL ANALYSIS WITH 3D SCANNING AND THREE-DIMENSIONAL MODELLING OF THE MAIN CHURCH OF ST. MARY – THE OLD CATHEDRAL, CARTAGENA (REGION OF MURCIA, SPAIN)

Abstract. The former Church of St. Mary, known as the Old Cathedral, in Cartagena (Region of Murcia, Spain), is a construction from the beginning of the 13th century, but it was transformed in the 16th century and rebuilt at the beginning of the 20th century. The bombings occurring during the Spanish Civil War caused the partial collapse of the building and the state of ruin that it currently presents. It is protected as a PCI with the category of monument. A Master Plan is currently being developed that should lead to the recovery of the building. The "Thermal Analysis and Geomatics (TAG)" Research Group of the Polytechnic University of Cartagena has collaborated in the drafting of the Master Plan with a planimetric survey and graphic analysis of the entire building. For this purpose, digital terrestrial photogrammetry techniques and a 3D laser scanner compatible with classical topography have been used, in order to obtain an accurate three-dimensional model. All this graphic information has been contrasted with the historical, typological, material and constructive information currently available about the building, which has facilitated the making of an exhaustive three-dimensional analysis that permits us to know this ancient Cathedral in depth. This paper will describe the work methodology followed, the technical means used and the results achieved, which have been incorporated into the Master Plan that is being prepared. Undoubtedly, the digital analysis has helped to obtain a better general understanding of the building and to be able to propose a correct formal, structural and material recomposition.

Establishing relationships between structural data from close-range terrestrial digital photogrammetry and measurement while drilling data

Geologists, mine planners, geotechnical, and mining engineers always strive for maximum information to get a better insight of the rock mass before interacting with it. Over the recent decades, close-range terrestrial digital photogrammetry (CRTDP) has been increasingly used for data acquisition and to support the conventional methods for rock mass characterization. It provides a safe, time-saving and contact-free way to gather enough data to minimize user dependent biases. However, it requires an expensive camera, fieldwork and some software to extract the information from images. In addition, it can over-estimate the rock fracturing sometimes due to weathering of the rock face or poor blasting practices. Measurement while drilling (MWD) data include the responses of different drilling parameters to the variations in the rock mass. MWD data are produced in large quantity, as they come from every hole drilled. These data correspond to the inside variations of rock rather than the surface ones counted in photogrammetry.In this paper, structural data are obtained from different bench faces of an open pit mine using a commercial software package, ShapeMetriX3D (by 3GSM). These data are compared to the MWD data of the boreholes that were blasted to produce these bench faces to establish certain relationships between drilling parameters and rock mass structures. Half casts of the boreholes with MWD data were visible on the bench faces of the pre-split wall that allowed a better correlation. The results show abrupt changes in MWD parameters for open joints or cavities with some infilling material and overall increases or decreases in parameters for closely spaced bedding planes, fractures or foliations. The results are promising and suggest the method can be used to characterize the rock mass, modify the charging of explosives in blasting operations and facilitate the geological modeling of the rock mass.

USING DIGITAL TERRESTRIAL PHOTOGRAMMETRY IN CULTURAL HERITAGE CASE STUDY: THE GREAT WALL OF GORGAN IN IRAN

Abstract. An assessment of the influence of using digital terrestrial photogrammetry for surveying and documentation of cultural objects is presented in this paper. The approaches including digital image enhancement, digital rectification and restitution, feature extraction for the creation of a three-dimension geographical information system model from the photogrammetric record and the computer visualisation of cultural monuments. Manual three-dimension processing of terrestrial images using analogue photogrammetric procedures is slow, can register little information and has limited application and cannot be re-examined if the information desired is not directly presented. In addition, it is a very time-consuming task and requires the skill of qualified personnel. It seems there is a need for an environment-based information system with the ability to display precise and measurable imagery for use of the architectural and archaeological information system by integrating digital photogrammetry and AutoCAD facilities as applicable to support the reconstruction of many cultural heritage places. Architectural structuring and guidelines can be used to develop invaluable historical monuments in Iran such as the Great Wall of Gorgan. While the research is in completion, the output of the Great Wall of Gorgan can be documented and recorded in the world.

The utility of terrestrial photogrammetry for assessment of tree volume and taper in boreal mixedwood forests

Key MessageThis study showed that digital terrestrial photogrammetry is able to produce accurate estimates of stem volume and diameter across a range of species and tree sizes that showed strong correspondence when compared with traditional inventory techniques. This paper demonstrates the utility of the technology for characterizing trees in complex habitats such as boreal mixedwood forests.ContextAccurate knowledge of tree stem taper and volume are key components of forest inventories to manage and study forest resources. Recent developments have seen the increasing use of ground-based point clouds, including from digital terrestrial photogrammetry (DTP), to provide accurate estimates of these key forest attributes.AimsIn this study, we evaluated the utility of DTP based on a small set of photos (12 per tree) for estimating stem volume and taper on a set of 15 trees from 6 different species (Populus tremuloides, Picea glauca, Pinus contorta latifolia, Betula papyrifera, Picea mariana, Abies balsamea) in a boreal mixedwood forest in Alberta, Canada.MethodsWe constructed accurate photogrammetric point clouds and derived taper and volume from three point cloud–based methods, which were then compared with estimates from conventional, field-based measurements. All methods were evaluated for their accuracy based on field-measured taper and volume of felled trees.ResultsOf the methods tested, we found that the point cloud–derived diameters in a taper curve matching approach performed the best at estimating diameters at the lowest parts of the stem (< 30% of total tree height), while using known DBH and height provided more accurate estimates for the upper parts of the stem (> 50% of total height). Using the field-measured DBH and height as inputs to calculate stem volume yielded the most accurate predictions; however, these were not significantly different from the best point cloud-based estimates.ConclusionThe methodology confirmed that using a small set of photographs provided accurate estimates of individual tree DBH, taper, and volume across a range of species and size gradients (10.8–40.4 cm DBH).

How to survey, model, and measure rockeries in a Chinese classical garden: a case study for Huanxiu Shanzhuang, Suzhou, China

ABSTRACTRockeries, which imitate nature in a special form, are an essential element of Chinese classical garden design and one of the most fascinating features that distinguish Chinese culture from other traditions of the world. This study takes rockeries in Huanxiu Shanzhuang—one of the exceptional rockeries in China—as an example to study the methods of digital survey, documentation and research of Chinese cultural heritage. Using techniques of terrestrial laser scanning and digital photogrammetry, this study made surveys, 3D models and morphometric measurements of piled mountains and single monoliths in Huanxiu Shanzhuang. A survey and document approach for different kinds of rockeries in Chinese classical gardens was studied by comparing the related techniques applied in different situations. Using the methods studied in this research, rockeries in Huanxiu Shanzhuang were documented and measured.

Semantic-based 3D information modelling and documentation of rockeries in Chinese classical gardens: A case study on the rockery at Huanxiu Shanzhuang, Suzhou, China

Abstract Rockery, or Jia Shan, representing a high level of artistic achievement and aiming to show Chinese landscapes and culture, is an essential part of Chinese classical gardens. Taking the rockery in the backyard of Huanxiu Shanzhuang as an example, this study undertook digital measurements and 3D reality-based modelling, carried out semantic-based analysis and modelling, and built a 3D information system. The digital survey applied the integrated techniques of terrestrial digital photogrammetry and laser scanning. Once the integrated 3D digital data had been obtained, the rockery was systematically and clearly analyzed for its structure on the base of its relationship with mountains in nature. By obtaining the hierarchical and spatial relationships between rockery components, the rockery and its components were semantically named and modelled. According to the rockery analysis results, the 3D reality-based models were segmented into numbers of rockery components, and a 3D information system was built on the basis of a 3D geographic information systems (3D GIS). Through these methods, all the data and information obtained from the rockery on the study site were documented, stored, managed, and visualized. This research showed that rockeries in Chinese classical gardens and cultural heritage sites with similar characteristics can be digitally, informationally, and systematically documented, studied, and preserved.

GIS and three-dimensional modeling for cultural heritages

Cultural heritages are the history of the nations, and history forms the identities of the nations. Therefore, protection of cultural heritages means protection of the history and identity of the nations. Identification of the current status of cultural heritages is important for documentation, preservation, and for use as a base for restoration. Documentation studies need robust and scientific methods. GIS and photogrammetry have recently been the most commonly used scientific methods for documenting cultural heritages. The aim of this study is investigate the photogrammetric method and GIS for documentation of cultural heritages digitally. In documentation studies, digital terrestrial photogrammetry is one of the main methods of processing information of historical monuments on computers according to GIS and documenting it in three dimensions. In this study for documentation, all data of 46 historical monuments located in Silifke/Mersin were collected and transferred to a database so that it is made queryable. Some of those heritages were reconstructed as 3D models by the use of photogrammetric techniques. Finally, 3D Models were integrated into the system for presentation.

The Proposed Algorithm for Modelling of Ancient Monuments and Cultural Heritage by using of Hyperspectral Images Data and Digital Terrestrial Photogrammetry

The Proposed Algorithm for Modelling of Ancient Monuments and Cultural Heritage by using of Hyperspectral Images Data and Digital Terrestrial Photogrammetry

Novel 3D geometry and models of the lower regions of large trees for use in carbon accounting of primary forests.

There is high uncertainty in the contribution of land-use change to anthropogenic climate change, especially pertaining to below-ground carbon loss resulting from conversion of primary-to-secondary forest. Soil organic carbon (SOC) and coarse roots are concentrated close to tree trunks, a region usually unmeasured during soil carbon sampling. Soil carbon estimates and their variation with land-use change have not been correspondingly adjusted. Our aim was to deduce allometric equations that will allow improvement of SOC estimates and tree trunk carbon estimates, for primary forest stands that include large trees in rugged terrain. Terrestrial digital photography, photogrammetry and GIS software were used to produce 3D models of the buttresses, roots and humus mounds of large trees in primary forests dominated by Eucalyptus regnans in Tasmania. Models of 29, in situ eucalypts were made and analysed. 3D models of example eucalypt roots, logging debris, rainforest tree species, fallen trees, branches, root and trunk slices, and soil profiles were also derived. Measurements in 2D, from earlier work, of three buttress 'logs' were added to the data set. The 3D models had high spatial resolution. The modelling allowed checking and correction of field measurements. Tree anatomical detail was formulated, such as buttress shape, humus volume, root volume in the under-sampled zone and trunk hollow area. The allometric relationships developed link diameter at breast height and ground slope, to SOC and tree trunk carbon, the latter including a correction for senescence. These formulae can be applied to stand-level carbon accounting. The formulae allow the typically measured, inter-tree SOC to be corrected for not sampling near large trees. The 3D models developed are irreplaceable, being for increasingly rare, large trees, and they could be useful to other scientific endeavours.

Weak foliated rock slope stability analysis with ultra-close-range terrestrial digital photogrammetry

This paper presents a review of the data acquisition procedures of geotechnical parameters for rock slope stability assessment and the proposal of some new improvements. For this purpose, a piece of research based on the slope mass rating classification system using close-range terrestrial digital photogrammetry (CR-TDP) has led to improvements in quality and timing of discontinuity data acquisition, and analyzes the suitability of each one of the parameters when applied to weak foliated rocks. TDP allows rapid 3D image acquisition of a rock slope, which can be analyzed using software to determine the geometrical parameters that affect stability. A fast procedure to perform the photogrammetric, non-contact survey in order to obtain the 3D images is shown in this paper. Being a rapid and single-person task, this procedure provides enough precision to be applied to weak foliated rock slopes with non-well-defined geometry. Furthermore, the study has focused on highly foliated rock outcrops, in which high resolution in the 3D images is very desirable. This research was applied to mountain road cuts, in which the use of TDP with a very close range was necessary. Through an application on weak rocks in the Alpujarras (Andalusia, Spain), this work analyzes the bias when applying TDP to materials such as these, under progressive weathering processes.

A field investigation of application of digital terrestrial photogrammetry to characterize geometric properties of discontinuities in open-pit slopes

In order to analyze the slope stability in open-pit mines, the structural parameters of rock mass such as persistence and spatial orientation of discontinuities are characterized through field surveys, which involve spending high costs and times as well as posing high risks of rock toppling and rock fall. In the present work, a new application of terrestrial digital photogrammetry is introduced for characterizing the rock mass structural parameters through preparing photogrammetry images from open-pit walls and building stereomodels. The data extracted from processing the stereo-model generations using photogrammetry images with different focal distances are highly consistent with the data collected through field surveys. However, it must be noted that the weather conditions, natural lighting angle, and applied observation scale may considerably affect the results obtained from stereomodel processing. Nevertheless, by taking into account the parameters such as time, cost, and full access to the required data, this new method can effectively be used in the estimation of rock mass structural parameters for analysis of steep slopes in open pits.

Calculation the Spacing of Discontinuities from 3D Point Clouds

The influence of discontinuities on the mechanical behavior of rock masses, demands a detailed knowledge about the geometrical properties of the existing discontinuity network. Traditional measurement techniques provide a rough knowledge about a discontinuity network but are also prone to bias. To increase the reliability of discontinuity models, remote sensing techniques like Close-Range Terrestrial Digital Photogrammetry (CRDTP) are increasingly applied for rock mass characterization. This research contributes to the trend of automatic rock mass characterization and focuses on the analysis of a digital surface model. This paper proposes a method to identify discontinuity sets in a point cloud and calculate the spacing of the sets. The discontinuity sets are semi-automatically identified with the open-source software DSE (Discontinuity Set Extractor). The program analyzes the density distribution of the point normal vectors in combination with a co-planarity test. The subsequent calculations apply DBSCAN to cluster and assign the points in the point cloud to singe discontinuity sets. After identifying the different discontinuity sets, the sub-members of each discontinuity set are again searched with DBSCAN in Matlab® (The Mathworks Inc.) and exported as a structure map to calculate the normal spacing between the single members of each set with ShapeMetriX3D Analyst. The point cloud is generated with CRTDP, using the digital mapping tool ShapeMetriX3D (3GSM GmbH), which is also used to validate the results of the calculations.

Inside the polygonal walls of Amelia (Central Italy): A multidisciplinary data integration, encompassing geodetic monitoring and geophysical prospections

We investigate a portion of the ancient (VI and IV centuries BC) polygonal walls of Amelia, in Central Italy. After the collapse of a portion of the walls which occurred in January 2006, a wide project started in order to monitor their external facade and inspect the characteristics of the internal structure, currently not clearly known. In this specific case, the preservation of such an important cultural heritage was mandatory, therefore invasive methods like drilling or archaeological essays cannot be used. For this purpose, a multidisciplinary approach represents an innovative way to shed light on their inner structure. We combine several non-invasive techniques such as Ground Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT), specifically adapted for this study, Laser Scanning and Digital Terrestrial Photogrammetry, integrated with other geomatic measures provided by a Total Station and Global Navigation Satellite Systems (GNSS). After collecting some historical information, we gather the whole datasets exploring for their integration an interpretation approach borrowed from the reflection seismic (attribute analysis and three dimensional visualization). The results give rise for the first time to the internal imaging of this ancient walls, highlighting features associable to different building styles related to different historical periods. Among the result, we define a max wall thickness of about 3.5m for the cyclopic sector, we show details of the internal block organization and we detect low resistivity values interpretable with high water content behind the basal part of the walls. Then, quantitative analyses to assess their reliable geotechnical stability are done, integrating new geometrical constrains provided by the geophysics and geo-technical ground parameters available in literature. From this analysis, we highlight how the Amelia walls are interested, in the investigated sector, by a critical pseudo-static equilibrium.