3D Survey Research Articles

Systematic integration of 2D and 3D sources for the virtual reconstruction of lost heritage artefacts: the equestrian monument of Francesco III d’Este (1774–1796, Modena, Italy)

The role of 3D virtual reconstruction of lost heritage artefacts is acquiring ever-greater importance, as a support for archaeological research and art history studies, as well as a vehicle for the cultural and evocative involvement of the end-user. The main risk of virtual reconstruction is the lack of a faithful restitution but, conversely, very often the artefact conservation state does not allow a complete 3D reconstruction. Therefore, 2D sources, both textual and iconographic, represent a precious integration and completion of the existing 3D sources. This paper proposes an operating systematic workflow to integrate retrieved 2D and 3D sources and assess their compatibility for the virtual reconstruction of lost heritage artefacts using and integrating 3D survey and digital modelling. As a case study, we virtually reconstructed the lost equestrian monument of Duke Francesco III d'Este, 7 m high, built in 1774 in Modena, Italy, by the sculptor Giovanni Antonio Cybei and completely destroyed a little over 20 years later during the revolutionary uprisings. Following the proposed workflow, we integrate data coming from: a still preserved preparatory stucco model, paintings and engravings showing the missing details of the 3D model, a series of urban views returning the proportion and positioning of the monument (statue, pedestal and base), a fragment of the right foot providing the statue size and the appearance of the original white Carrara marble. The final 3D digital model shows a faithful correspondence to the 2D sources and guarantees an effective user’s fruition thanks to dedicated virtual applications. Besides the scientific and cultural goal, we highlight the evocative role of this work, which has contributed to the restitution of a monument that is unknown to most citizens and visitors.

A Combined Study of Cultural Heritage in Archaeological Museums: 3D Survey and Mixed Reality

Nowadays, a great interest in historical installations like museographic devices in international museological studies (capable of giving space form during user communication) is largely attributable to new techniques of immediate communication. Tools and libraries for virtual, augmented, and mixed reality content have recently become increasingly available. Despite its increased cost and investment, these are new ways for increasing visitor presence in museums. The purpose of this paper is to describe the potential of a tourist/archaeological application suitably developed and implemented by us. The application was developed in Unity3D and allows the user to view cultural heritage in a virtual environment, making information, multimedia content, and metrically precise 3D models available and accessible (obtained after a phase of reducing the mesh border), useful for obtaining good 3D printing reproduction. The strengths of our application (compared to the many already in the literature, which are also used as research ideas) stem from the possibility of using and easily integrating different techniques (3D models, building information models, virtual and augmented reality) allowing the choice of different 3D models (depending on the user’s needs) on some of which (again depending on the application needs) were tested and performed simplification and size reduction processes, to make the application loading phase faster and the user experience easier and better. Another application cue was to finalize an application to relate the elements of the museum with some archaeological elements of the territory according to historical period and element type.

The integration of 3D technology for the conservation and restoration of ruined archaeological artifacts

The restoration and conservation of monuments and archaeological sites is a delicate operation. It requires fidelity, delicacy, precision and archaeological authenticity. The aim is to reveal, recreate as accurately as possible the characteristics of an archaeological site or part of it. Research during the last two decades has proved that 3D modeling, or the digital documentation and visualization of archaeological objects in 3D, is valuable for archaeological research. As well, as for conservation and presentation to a wide audience, as it allows the creation of realistic and accurate digital copies of archaeological objects. In the past, 3D modeling technologies were prohibitively expensive and too technologically specialized to be integrated into most historical heritage projects. However, advancements in computing and digital photography over the past decade have resulted in several low-cost, user-friendly options for 3D modeling, using photogrammetry. The latter has been used successfully for documentation of historic cultural. In recent years, this technology has become increasingly more popular for archiving, which provide the 3D model and digital ortho-image using high accuracy dense 3D points. The study has opted for the technique of terrestrial and aerial photogrammetry by 3D surveys of architectural elements, to develop an archetype of the deteriorated Islamic Marinid site (a dynasty between the 13th and 15th centuries), and the Roman site (25 BC), located at the Chellah archaeological site in Rabat and Salé cities. However, the recognition of the importance of these Islamic sites, in terms of the evolution of Moroccan Islamic art, requires the combination of large-scale scanning capability of unmanned terrestrial, aerial photogrammetry and the photorealistic rendering of 3D, as well as exhaustive research on the history of this cultural site. The data acquired build an architectural database to archive and retrieve the entire existing architecture of monuments. This study has been completed by photogrammetrists, architects, and restorers.

PREFACE

PREFACE

Concurrent 14. Presentation for: Major geological surfaces of the Exmouth Plateau from the new Broadband PreSDM reprocessed 3D seismic data with full waveform inversion

Presented on Wednesday 18 May: Session 14 The Barrow Sub-basin and Exmouth Plateau, of Australia’s North West Shelf, contain Australia’s largest gas reserves, underpinning the three major LNG facilities, including Gorgon, Wheatstone and Pluto. In addition, there remains significant near-field exploration potential such as the Sasanof prospect. While there is full 3D seismic coverage in the basin, the existing 3D surveys are of different vintages covering only parts of the basin with diverse acquisition and processing parameters. Multi-Client Resources has produced an extensive 3D seismic reprocessing project (BEX-MC3D) incorporating 23 legacy 3D surveys to provide a seamless 25 570 km2 3D dataset. The BEX-MC3D was processed from field tape through DUG Technology’s advanced Broadband PreSDM processing sequence with Full Waveform Inversion (FWI) imaging. The BEX-MC3D provides one continuous superlative 3D dataset covering almost the entire Barrow Sub-basin and the Exmouth Plateau. Major geological surfaces corresponding to key tectonic events from overburden to reservoirs have been interpreted from the BEX-MC3D Priority area in the current study. These high-fidelity imaged surfaces form a basin-wide framework for: (1) rapid exploration lead and prospect identification through the creation of trap and reservoir visualisations; (2) improved reservoir connectivity analysis and modelling of producing and discovered fields to support better reservoir management and field development decisions; and (3) improved understanding of basin-burial history for reservoir quality and geo-mechanical property prediction. This paper will present and discuss major geological surfaces in the context of future exploration lead/prospect identification, reservoir characterisation for field development and management, and improving overall understanding of the basin history. To access the presentation click the link on the right. To read the full paper click here

Building 3D CityGML Model and Digital Management of a Vernacular Architecture

The aim of the paper is to discuss the Levels Of Details (LODs) of 3D city models in order to assess the constructive and semantic characteristics that distinguish each of them. The standard approach used in order to build the 3D model is the CityGML 3.0 Conceptual Model. A key role for the development of the CityGML Conceptual Model is to provide a common definition of the basic entities, attributes, and relations of a semantically rich 3D city model. This approach is important with respect to the cost-effective sustainable maintenance of 3D city models, allowing the reuse of the same data in different application fields. In this context, we have developed a method to build a 3D CityGML model using SketchUP software and some of the tools implemented in it. In addition, the constructed model was displayed and validated by using an open source software (FZK viewer). The building taken into consideration is a vernacular dwelling structure called “trullo” (plural “trulli”) and present in the Apulia region, Italy. “Trulli” are extraordinary examples of dry stone construction with conical or pyramid-shaped roof made with slabs, a technique dating back to prehistoric times and still in use today in Apulia. Before building the 3D model, it was necessary to perform the 3D survey of the building; this task was carried out by using Terrestrial Laser Scanner (TLS) that allowed a realistic and detailed reconstruction of the structures. From the point cloud, a special procedure was developed in order to build CityGML models in several LODs.

3D MODELLING OF TRAM TUNNEL FROM TLS POINT CLOUDS FOR TECHNICAL DOCUMENTATION AND EXTRACTION OF CHARACTERISTIC LINES

Abstract. The Strasbourg tramway has only one tunnel 1400 m long built in 1994. It grants the operation of two lines of the transportation network. It also houses the only underground station "Gare centrale" and is the only tunnel operated by the CTS (Compagnie des Transports Strasbourgeois). Due to new guidelines for georeferencing of underground networks, the CTS had to know the precise planimetric and altimetric position of the tunnel, considered as a sensitive network located in urban areas. The regulations also set the criteria for precision which for this specific case requires an accuracy of less than 40 cm. This project on behalf of and in partnership with the CTS therefore aims to set up a method allowing the 3D survey of the tunnel considering the specific constraints of urban transport networks and then to propose different 2D or 3D deliverables allowing the management of the tunnel. Initially, the project focused on extracting the shape of the tunnel characteristic lines, which corresponds to the line tangent to the points of higher altitude and the extreme points of each cross-section, along the axis of the tunnel. In a second step, a 2D plan containing all the technical elements present in the tunnel was realized, as well as a 3D modelling of a significative part of the infrastructure. A video was also derived from the point cloud to inspect the entire tunnel from different points of views. In the future, more advanced 3D models or BIM models could be considered. This would require information on the structure of the walls, the construction materials, or the links between the different elements. A project to survey and model the underground station will make it possible in the future to perfect the acquisition and knowledge of the underground infrastructures belonging to the transport company.

APPLICATION OF CONSUMER–LEVEL UAV PHOTOGRAMMETRY IN DIGITAL SURVEY OF CLIFF-BURIAL CULTURE RELICS: A CASE STUDY OF MOUNT WUYI

Abstract. The cliff-burial was an ancient funerary ritual once popular in the Far East Asia (Figure 1), in which the dead were buried high on the cliffs with log coffins (the “hanging coffins”) left in the natural caves, excavated grottoes or on some wood piles.In view of the fact that the cliff-burial sites are usually located on the escarpments overlooking the rivers and with great slope, where the conventional 3D survey means, such as ground laser scanning and traditional aerial photogrammetry, is out of option. This study explores the possibility of using UAV (consumer–level drone) with substantial improvement in survey accuracy, range and flight control (Figure 2), which aims to lay the foundation for the global cliff-burial culture heritage research. A survey method extendible on other excavated funeral sites would be tested and codified, as a possible follow up of the research on some study cases in Far East Asia and Europe.

NEW DEVELOPMENTS IN LIDAR UAS SURVEYS. PERFORMANCE ANALYSES AND VALIDATION OF THE DJI ZENMUSE L1

Abstract. Thanks to the latest technological developments LiDAR (Light Detection And Ranging) sensors are no longer an exclusive feature of manned airborne platforms but they are close to becoming a commercial solution in the UAS (Uncrewed Aerial Systems) domain. The release on the market of the Zenmuse L1 by DJI (Dà-Jiāng Innovations) is a step further in this direction, thanks also to a substantial work of enhancement made by the Chinese company not only on the hardware side, but also on the software one. The research presented in this work is focused on the use of the L1 LiDAR for the 3D survey of built heritage, analysing the results of different tests to highlight first considerations on its performances and the point cloud quality. Considering its recent release, this sensor is still yet to be thoroughly analysed and validated and its performances to be assessed. LiDAR data has been acquired on a selected test site, documented also with traditional Terrestrial Laser Scanner (TLS) and UAS photogrammetry. The latter techniques (supported also by a topographic survey) will thus be exploited to generate the ground reference and to assess the quality and accuracy of the L1 dataset.

Major geological surfaces of the Exmouth Plateau from the new Broadband PreSDM reprocessed 3D seismic data with full waveform inversion

The Barrow Sub-basin and Exmouth Plateau, of Australia’s North West Shelf, contain Australia’s largest gas reserves, underpinning the three major LNG facilities, including Gorgon, Wheatstone and Pluto. In addition, there remains significant near-field exploration potential such as the Sasanof prospect. While there is full 3D seismic coverage in the basin, the existing 3D surveys are of different vintages covering only parts of the basin with diverse acquisition and processing parameters. Multi-Client Resources has produced an extensive 3D seismic reprocessing project (BEX-MC3D) incorporating 23 legacy 3D surveys to provide a seamless 25 570 km2 3D dataset. The BEX-MC3D was processed from field tape through DUG Technology’s advanced Broadband PreSDM processing sequence with Full Waveform Inversion (FWI) imaging. The BEX-MC3D provides one continuous superlative 3D dataset covering almost the entire Barrow Sub-basin and the Exmouth Plateau. Major geological surfaces corresponding to key tectonic events from overburden to reservoirs have been interpreted from the BEX-MC3D Priority area in the current study. These high-fidelity imaged surfaces form a basin-wide framework for: (1) rapid exploration lead and prospect identification through the creation of trap and reservoir visualisations; (2) improved reservoir connectivity analysis and modelling of producing and discovered fields to support better reservoir management and field development decisions; and (3) improved understanding of basin-burial history for reservoir quality and geo-mechanical property prediction. This paper will present and discuss major geological surfaces in the context of future exploration lead/prospect identification, reservoir characterisation for field development and management, and improving overall understanding of the basin history.

A cost-effective three-dimensional marine controlled-source electromagnetic survey: Exploring seafloor massive sulfides

A 3D marine controlled-source electromagnetic (CSEM) survey for mapping hydrocarbons uses dozens of ocean-bottom electric (OBE) receivers deployed in a grid pattern and several transmitter towlines. This study considers seafloor massive sulfides (SMS) exploration, and the horizontal survey scale of SMS is a few kilometers, which is small compared with hydrocarbon surveys of tens of kilometers. If we apply a 3D CSEM survey using a receiver deployment on grids to map SMS, high survey costs will be incurred despite the small survey size. We have developed a cost-effective 3D marine CSEM survey that uses fewer receivers than the survey with a receiver deployment on grids to reduce survey costs for SMS. This CSEM survey uses a line of OBE receivers in the center of the survey area and several transmitter towlines. Numerical tests demonstrate that our survey (seven OBE receivers) using 80% fewer receivers than the survey with a receiver deployment on grids (35 OBE receivers) is able to accurately map SMS, obtaining a performance similar to that of the receiver deployment on grids. Then, we explore SMS in the Ieyama hydrothermal area off Okinawa, southwest Japan, using our 3D CSEM survey with a line of six OBE receivers and three transmitter towlines. The resulting 3D resistivity distribution from the observed data highlights three potential SMS zones consisting of 0.2 ohm-m low resistivity embedded into 1 ohm-m sediment.

Preservation of Villages in Central Italy: Geomatic Techniques’ Integration and GIS Strategies for the Post-Earthquake Assessment

Historical villages represent a highly vulnerable cultural heritage; their preservation can be ensured thanks to technological innovations in the field of geomatics and information systems. Among these, Geographical Information Systems (GISs) allow exploiting heterogeneous data for efficient vulnerability assessment, in terms of both time and usability. Geometric attributes, which currently are mainly inferred by visual inspections, can be extrapolated from data obtained by geomatic technologies. Furthermore, the integration with non-metric data ensures a more complete description of the post-seismic risk thematic mapping. In this paper, a high-performance information system for small urban realities, such as historical villages, is described, starting from the 3D survey obtained through the integrated management of recent innovative geomatic sensors, such as Unmanned Aerial Vehicles (UAVs), Terrestrial Laser Scanners (TLSs), and 360º images. The results show that the proposed strategy of the automatic extraction of the parameters from the GIS can be generalized to other case studies, thus representing a straightforward method to enhance the decision-making of public administrations. Moreover, this work confirms the importance of managing heterogeneous geospatial data to speed up the vulnerability assessment process. The final result, in fact, is an information system that can be used for every village where data have been acquired in a similar way. This information could be used in the field by means of a GIS app that allows updating the geospatial database, improving the work of technicians. This approach was validated in Gabbiano(Pieve Torina), a village in Central Italy affected by earthquakes in 2016 and 2017.

3D penta-source marine seismic acquisition: an innovative approach to address the sampling challenge

Penta-source acquisition is the latest addition to modern 3D Marine Seismic Acquisition Methods, a step ahead of the conventional dual and the more recent triple source acquisition methods. In the recent years, it has increasingly become popular due to its ability to deliver higher quality data enabled by finer cross-line sampling. This has been demonstrated through the Baxter Case Study (Hager et. all, 2016) where the 3D survey was successfully acquired and processed though the study area was relatively small. We present a case study from offshore Malaysia where penta-source acquisition method was adopted for the first time for a large 3D survey (~7000 sq.km) to enhance the data quality without compromising the acquisition efficiency. The survey was designed using a robust workflow to optimize acquisition parameters to meet the geophysical objectives, and executed safely and efficiently.

Digital survey and reconstruction for enhancing epigraphic readings with erode surface

Abstract The contribution illustrates the applied procedure of the digital survey and documentation of a funerary epigraph written in Greek but dating back to the Roman period (dimensions of about 31 cm x 20 cm). It comes from Velia (Salerno), a Greek and then Roman city in southern Italy. It was found in 1967 and currently represents the only Greek funerary inscription of the Roman period coming, most probably, from the necropolis of Porta Marina Sud. The inscription presents many gaps and preserves only part of the upper right and lower margins. The surface is highly eroded, maybe due to the exposure to atmospheric agents, making the text interpretation extremely difficult. The implemented image-based and range-based techniques contributed to reading the inscriptions, letting to recover much information that was invisible to the naked eye. The 3D survey system choice has to be consistent with the work aims and the physical object characteristics. A high degree of geometric detail was essential for our case study. Therefore, a triangulation laser scanner performed the first digital capturing, subsequently integrated with a structured light system (Artec Eva and Leo) and finally, a close-range photogrammetric acquisition to produce a high-resolution orthophoto.

The Virtual Reconstruction of the Aesculapius and Hygeia Statues from the Sanctuary of Isis in Lilybaeum: Methods and Tools for Ancient Sculptures’ Enhancement

Thanks to recent technological developments in 3D surveys, computer graphics and virtual reality, new scenarios have been opened for the documentation and enhancement of ancient sculptures. When not totally preserved, sculptures can be digitally reproduced, modified and visualized to simulate their physical or virtual reconstruction in a non-invasive way for specialists or for dissemination aims. The virtual sculptural reconstruction process starts usually from the 3D survey of real fragments, and then continues by integrating missing parts with 3D modelling techniques by means of source evaluation. Along with primary data sources (reality-based model), secondary data sources (photos, drawings and 3D models of similar sculptures) can be directly used in the reconstruction process. This approach has a double advantage of making the reconstruction activities easier and less arbitrary, contributing to a decrease in the degree of uncertainty for the sculptural reconstruction work, also thanks to many iconographic comparisons to ancient copies. Moreover, virtual reconstruction can be easily visualized alongside a scalable rendering system using open-source Web3D apps and platforms, accessing information, 3D models and descriptions in order to enhance the experience of artworks. Inspecting theoretical and technical approaches, this work aims at establishing how primary and secondary data sources can be effectively used in sculptural reconstruction workflows, and how 3D outputs can be applied to implement digital sculptural heritage exploitation for museums and cultural institutions. The statues of Aesculapius and Hygeia from the sanctuary of Isis in Lilybaeum (Marsala, Italy) were chosen as a case study.

La Tomba di Giulio II a Roma: dal rilievo fotogrammetrico alla stampa 3D per non vedenti

3D printing artefacts and monuments allows blind and visually impaired people to discover,understand and enjoy the beauty of Cultural Heritage. The reproduction of the artefactsusually starts with the 3D survey with reality-based techniques in order to obtain their metric,accurate digital copy. With a proper post-processing, the digital model is then set up ready forthe printing. The result is a physical model that can be touched and inspected, making the artvisible to everyone.This paper presents the pipeline followed for the 3D reproduction of the famous Michelangelo’sTomb of Giulio II, visible in San Pietro in Vincoli church in Rome. The photogrammetricsurvey is descripted and evaluated, and all the process followed to postprocess the 3D modelin order to make it countable for the 3D printing. A particular attention was given to theproblems occurred during the survey (lack of space, lights) and then the postprocessing relatedto the creation of different printed physical models. The fi nal models have been printed inaccomplish with the requests of the costumer, in order to make them suitable for blind people.

3D resistivity survey over mapped caves in eogenetic karst terrane, west-central Florida, USA

This study assesses the capability and practical applications of quasi-3 Dimensional (3D) Electrical Resistivity Tomography (ERT) for mapping air-filled conduits in eogenetic karst. A high-resolution quasi-3D ERT survey, consisting of multiple parallel 110m-long 2D profiles, was conducted over two mapped cave systems on the Brooksville Ridge, Florida. The irregularly shaped caves have diameters ranging up to 4 m and span depths from 3 m to 11 m below ground surface. Dipole-dipole array geometries with L2 (least squares) rather than L1 (robust) inversion produced the best fits of resistivity highs with the mapped cave locations. As expected, 3D inversions of sets of parallel lines produced better results than 2D inversions of individual transects. Better imaging was obtained of a cave over which cave-parallel profiles were run in addition to cross-cave profiles. However, even with the best acquisition and processing steps, there are significant misfits in the apparent size of the large cave sections, and narrower conduits are not imaged. Resolution decreased significantly with depth, as expected given the method limitations and the site constraints on profile lengths. 3D visualization techniques are explored, and found helpful in examining the data and comparing mapped caves and 3D resistivity datasets; however, when applied to eogenetic karst terrain, ERT has limited capacity to detect smaller cavities, which may require the additional use of other geophysical or subsurface investigative methods. With sinkholes continuing to be of concern to residential and urban development in west-central Florida, the results of this research present additional insight on the potential of quasi-3D ERT methods to map and characterize the potential hazards posed by karst terranes.

Time-lapse seismic integrated with surface microseismic for SRV characterization in the Vaca Muerta Formation

Time-lapse (4D) seismic acquisitions were performed in the unconventional play of the Vaca Muerta Formation to monitor hydraulic stimulation efficiency and characterize the stimulated rock volume (SRV) in horizontal drains. Two 4D pilots were carried out by acquiring 3D surveys before and after hydraulic stimulation. The pilots targeted different stratigraphic landings characterized by distinct lithological and geomechanical properties. The 4D pilots were performed in synergy with surface microseismic acquisitions. The combined acquisition enabled joint interpretation of the results. Time-lapse acoustic inversions were performed to identify changes in acoustic impedance. They revealed the vertical dimension of the SRV more precisely than the analysis of the envelope of the wet microseismic events. These wet events are interpreted as hydraulically connected to the well. The 4D signal is interpreted as the envelope of the induced hydraulic fractures, defined here as the fractured rock volume. This volume refers to where the rock frame has been directly affected by the stimulation job. The image provided by 4D seismic represents the most direct and accurate measurement of the volume encircling the flow pathways created by the fracture network generated by the hydraulic stimulation. This information is key to assessing ultimate hydrocarbon recovery and optimizing the development of unconventional reservoirs. The added value of the microseismic is the mapping of subtle events associated with the reactivation of critically stressed faults/lineaments. These provide preferential pathways that could connect to the well. They also help in the understanding of hydraulic interactions between the wells and their individual SRVs. The findings of these studies indicate that the optimal lateral and vertical well spacing should be designed based on 4D monitoring for drainage optimization and on microseismic for the analysis of interwell structural interferences.

Performance comparison analysis of 3D reconstruction modeling software in construction site visualization and mapping

Unmanned aerial vehicle (UAV) technology has overcome the limitations of conventional construction management methods using advanced and automated visualization and 3D reconstruction modeling techniques. Although the mapping techniques and reconstruction modeling software can generate real-time and high-resolution descriptive textural, physical, and spatial data, they may fail to develop an accurate and complete 3D model of the construction site. To generate a quality 3D reconstruction model, the construction manager must optimize the trade-offs among three major software-selection factors: functionalities, technical capabilities, and the system hardware specifications. These factors directly affect the robust 3D reconstruction model of the construction site and objects. Accordingly, the purpose of this research was to apply nine well-established 3D reconstruction modeling software tools (DroneDeploy, COLMAP, 3DF+Zephyr, Autodesk Recap, LiMapper, PhotoModeler, 3D Survey, AgiSoft Photoscan, and Pix4D Mapper) and compare their performances and reliabilities in generating complete 3D models. The research was conducted in an eco-home building at the University of Technology, Malaysia. A series of regression analyses were conducted to compare the performances of the selected 3D reconstruction modeling software in alignment and registration, distance computing, geometric measurement, and plugin execution. Regression analysis determined that among the software programs, LiMapper had the strongest positive linear correlation with the ground truth model. Furthermore, the correlation analysis showed a statistically significant p-value for all software, except for 3D Survey. In addition, the research found that Autodesk Recap generated the most-robust and highest-quality dense point clouds. DroneDeploy can create an accurate point cloud and triangulation without using many points as required by COLMAP and LiMapper. It was concluded that most of the software is robustly, positively, and linearly correlated with the corresponding ground truth model. In the future, other factors involving software selection should be studied, such as vendor-related, user-related, and automation factors.

Application of 3D Surveying and Mapping Technology in Modern Engineering Survey

Application of 3D Surveying and Mapping Technology in Modern Engineering Survey