Workflow for 3D geovisualization of the data obtained with the use of Unmanned Aerial Vehicle in Augmented Reality

Abstract. The attempt to work out the geomatic workflow of transforming low-level aerial imagery obtained with unmanned aerial vehicles (UAV) into a digital terrain model (DTM) and implementing the 3D model into the augmented reality (AR) system constitutes the main problem discussed in this article. The authors suggest the following workflow demonstrated in Fig. 1.The series of pictures obtained by means of UAV equipped with a HD camera was the source of data to be worked out in the final stage of the geovisualization. The series was then processed and a few point clouds were isolated from it, being later used for generating test 3D models.The practical aim of the research conducted was to work out, on the basis of the UAV pictures, the 3D geovisualization in the AR system that would depict the heap of the natural aggregate of irregular shape. The subsequent aim was to verify the accuracy of the produced 3D model. The object of the study was a natural aggregate heap of irregular shape and denivelations up to 11 meters.Based on the obtained photos, three point clouds (varying in the level of detail) were generated for the 20&thinsp;000-meter-square area. The several-centimeter differences observed between the control points in the field and the ones from the model might corroborate the usefulness of the described algorithm for creating large-scale DTMs for engineering purposes. The method of transformation of pictures into the point cloud that was subsequently transformed into 3D models was employed in the research, resulting in the scheme depicting the technological sequence of the creation of 3D geovisualization worked out in the AR system. The geovisualization can be viewed thanks to a specially worked out mobile application for smartphones.

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Automated Generation of Digital Terrain Model using Point Clouds of Digital Surface Model in Forest Area

Remote Sensing ◽

10.3390/rs3050845 ◽

2011 ◽

Vol 3 (5) ◽

pp. 845-858 ◽

Cited By ~ 10

Author(s):

Kande R.M.U. Bandara ◽

Lal Samarakoon ◽

Rajendra P. Shrestha ◽

Yoshikazu Kamiya

Keyword(s):

Digital Terrain Model ◽

Point Clouds ◽

Forest Area ◽

Surface Model ◽

Digital Surface Model ◽

Automated Generation ◽

Terrain Model ◽

Digital Terrain

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Photogrammetric surveying forests and woodlands with UAVs: techniques for automatic removal of vegetation and digital terrain model production for hydrological applications

Journal of Unmanned Vehicle Systems ◽

10.1139/juvs-2016-0023 ◽

2019 ◽

Vol 7 (1) ◽

pp. 1-20

Author(s):

Fotis Giagkas ◽

Petros Patias ◽

Charalampos Georgiadis

Keyword(s):

Vegetation Type ◽

Digital Terrain Model ◽

Point Clouds ◽

Aerial Images ◽

Surface Model ◽

Terrain Model ◽

Vegetation Height ◽

Digital Terrain ◽

Dense Point ◽

Height Model

The purpose of this study is the photogrammetric survey of a forested area using unmanned aerial vehicles (UAV), and the estimation of the digital terrain model (DTM) of the area, based on the photogrammetrically produced digital surface model (DSM). Furthermore, through the classification of the height difference between a DSM and a DTM, a vegetation height model is estimated, and a vegetation type map is produced. Finally, the generated DTM was used in a hydrological analysis study to determine its suitability compared to the usage of the DSM. The selected study area was the forest of Seih-Sou (Thessaloniki). The DTM extraction methodology applies classification and filtering of point clouds, and aims to produce a surface model including only terrain points (DTM). The method yielded a DTM that functioned satisfactorily as a basis for the hydrological analysis. Also, by classifying the DSM–DTM difference, a vegetation height model was generated. For the photogrammetric survey, 495 aerial images were used, taken by a UAV from a height of ∼200 m. A total of 44 ground control points were measured with an accuracy of 5 cm. The accuracy of the aerial triangulation was approximately 13 cm. The produced dense point cloud, counted 146 593 725 points.

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3D-Modelling of Charlemagne’s Summit Canal (Southern Germany)—Merging Remote Sensing and Geoarchaeological Subsurface Data

Remote Sensing ◽

10.3390/rs11091111 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1111 ◽

Cited By ~ 3

Author(s):

Johannes Schmidt ◽

Johannes Rabiger-Völlmer ◽

Lukas Werther ◽

Ulrike Werban ◽

Peter Dietrich ◽

...

Keyword(s):

Cross Sections ◽

3D Model ◽

Digital Terrain Model ◽

Airborne Lidar ◽

Engineering Construction ◽

Terrain Model ◽

Digital Terrain ◽

Danube Catchment ◽

The Difference ◽

Airborne Lidar Data

The Early Medieval Fossa Carolina is the first hydro-engineering construction that bridges the Central European Watershed. The canal was built in 792/793 AD on order of Charlemagne and should connect the drainage systems of the Rhine-Main catchment and the Danube catchment. In this study, we show for the first time, the integration of Airborne LiDAR (Light Detection and Ranging) and geoarchaeological subsurface datasets with the aim to create a 3D-model of Charlemagne’s summit canal. We used a purged Digital Terrain Model that reflects the pre-modern topography. The geometries of buried canal cross-sections are derived from three archaeological excavations and four high-resolution direct push sensing transects. By means of extensive core data, we interpolate the trench bottom and adjacent edges along the entire canal course. As a result, we are able to create a 3D-model that reflects the maximum construction depth of the Carolingian canal and calculate an excavation volume of approx. 297,000 m3. Additionally, we compute the volume of the present dam remnants by Airborne LiDAR data. Surprisingly, the volume of the dam remnants reveals only 120,000 m3 and is much smaller than the computed Carolingian excavation volume. The difference reflects the erosion and anthropogenic overprint since the 8th century AD.

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An Augmented Reality Facility to Run Hybrid Physical-Numerical Flood Models

Water ◽

10.3390/w12113290 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3290

Author(s):

Jerónimo Puertas ◽

Luis Hernández-Ibáñez ◽

Luis Cea ◽

Manuel Regueiro-Picallo ◽

Viviana Barneche-Naya ◽

...

Keyword(s):

Augmented Reality ◽

Graphical User Interface ◽

Overland Flow ◽

Digital Terrain Model ◽

Entire System ◽

Terrain Model ◽

Digital Terrain ◽

Physical Scale ◽

Quantitative Results ◽

Simulation Results

This article presents a novel installation for the development of hybrid physical-numerical flood models in an augmented reality environment. This installation extends the concept introduced by the well-known Augmented Reality-SandBox (AR-Sandbox) module, which presents a more educational, and less research-based and professional application. It consists of a physical scale topography built in a sandbox into which other elements (such as buildings, roads or dikes) can be incorporated. A scanner generates, in real time, a Digital Terrain Model (DTM) from the sandbox topography, which serves as a basis for the simulation of overland flow using professional hydraulic software (Iber+). The hydraulic and hydrological parameters (surface roughness, inlet discharges, boundary conditions) are entered with a simple Graphical User Interface (GUI) developed specifically for this project, as indeed was the entire system that allows the visualization of the simulation results. This allows us to obtain quantitative results of flood extension and magnitude, which are represented directly over the physical topography, yielding a realistic visual effect. This installation is conceived for both educational and professional uses. An example of its use is presented, through which its accuracy can be appreciated, and which also illustrates its potential.

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Modeling Roman Pavements Using Heritage-BIM: A Case Study in Pompeii

The Baltic Journal of Road and Bridge Engineering ◽

10.7250/bjrbe.2020-15.482 ◽

2020 ◽

Vol 15 (3) ◽

pp. 34-46 ◽

Cited By ~ 2

Author(s):

Salvatore Antonio Biancardo ◽

Francesca Russo ◽

Rosa Veropalumbo ◽

Viktoras Vorobjovas ◽

Gianluca Dell’Acqua

Keyword(s):

3D Model ◽

Integrated Management ◽

Digital Terrain Model ◽

Archaeological Site ◽

Cost Information ◽

Technical Literature ◽

The Road ◽

Terrain Model ◽

Digital Terrain ◽

Site Survey

The study of ancient stone pavements represents the necessary premise for planning and execution of treatments that considers the necessity of conservation. The approach to the integrated management of information derived through H-BIM has been applied to Via del Vesuvio, one of the main roads in the archaeological site of Pompeii in Naples, Italy. The digital terrain model was carried out using Autodesk Infraworks software. Then, using Autodesk Civil 3D and Revit software, the road was digitalized creating the 3D model that included road geometric information resulting from an on-site survey, material characteristics for each pavement layer, construction period and related construction cost information. Finally, based on the existing research works available in the literature review, using Autodesk Naviswork software, it was possible to implement in the 3D model the BIM fourth dimension, namely, the time related to the construction of Via Del Vesuvio in different eras. The interoperability between the adopted BIM authoring software was exploited. The adopted procedure can be considered a benchmark case in the technical literature of H-BIM for stone pavements, highlighting the advantages in the design field.

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Aerial Laser Scanning Data as a Source of Terrain Modeling in a Fluvial Environment: Biasing Factors of Terrain Height Accuracy

Sensors ◽

10.3390/s20072063 ◽

2020 ◽

Vol 20 (7) ◽

pp. 2063 ◽

Cited By ~ 4

Author(s):

Zsuzsanna Szabó ◽

Csaba Albert Tóth ◽

Imre Holb ◽

Szilárd Szabó

Keyword(s):

Laser Scanning ◽

Digital Terrain Model ◽

Point Clouds ◽

Threshold Value ◽

Noise Filtering ◽

Terrain Model ◽

Digital Terrain ◽

Natural Neighbor ◽

Wide Range ◽

Ground Point

Airborne light detection and ranging (LiDAR) scanning is a commonly used technology for representing the topographic terrain. As LiDAR point clouds include all surface features present in the terrain, one of the key elements for generating a digital terrain model (DTM) is the separation of the ground points. In this study, we intended to reveal the efficiency of different denoising approaches and an easy-to-use ground point classification technique in a floodplain with fluvial forms. We analyzed a point cloud from the perspective of the efficiency of noise reduction, parametrizing a ground point classifier (cloth simulation filter, CSF), interpolation methods and resolutions. Noise filtering resulted a wide range of point numbers in the models, and the number of points had moderate correlation with the mean accuracies (r = −0.65, p < 0.05), indicating that greater numbers of points had larger errors. The smallest differences belonged to the neighborhood-based noise filtering and the larger cloth size (5) and the smaller threshold value (0.2). The most accurate model was generated with the natural neighbor interpolation with the cloth size of 5 and the threshold of 0.2. These results can serve as a guide for researchers using point clouds when considering the steps of data preparation, classification, or interpolation in a flat terrain.

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AUTOMATED MAPPING OF PERMANENT PRESERVATION AREAS ON HILLTOPS

CERNE ◽

10.1590/01047760201622012100 ◽

2016 ◽

Vol 22 (1) ◽

pp. 111-120 ◽

Cited By ~ 3

Author(s):

Guilherme de Castro Oliveira ◽

Elpidio Inacio Fernandes Filho

Keyword(s):

Large Scale ◽

Digital Terrain Model ◽

Map Algebra ◽

Automated Mapping ◽

Model Builder ◽

Terrain Model ◽

Digital Terrain ◽

Forest Code ◽

New Forest ◽

The Many

ABSTRACT Permanent Preservation Areas (PPAs) on hilltops are among the many areas protected by the New Forest Code in Brazil. Mapping of these involves difficult interpretation and application of the Law, as well a complex task of translating it in map algebra. This paper aims to present, in detail, a methodological model for delimitation of PPAs on hilltops, according to the Brazilian new Forest Code (NFC, Law 12,651/2012). The model was developed in Model Builder for ArcGIS 10.2, and is able to map the PPAs in any digital terrain model. However, field validations are required to verify its efficiency. There is need for legal standardization of criteria that may cause subjectivity in delimitation. The organization of these data on a large scale is very important, as example, to the Rural Environmental Registry, which provides georeferencing of all rural properties and its protected areas in Brazil.

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ANALYTICAL AND DIGITAL PHOTOGRAMMETRIC GEODATA PRODUCTION SYSTEMS (A COMPARISON TEST)

Geodesy and Cartography ◽

10.3846/13921541.2007.9636717 ◽

2012 ◽

Vol 33 (2) ◽

pp. 50-54 ◽

Cited By ~ 4

Author(s):

Birutė Ruzgienė ◽

Edita Aleknienė

Keyword(s):

Large Scale ◽

Production Systems ◽

Digital Terrain Model ◽

Terrain Model ◽

Digital Mapping ◽

Digital Terrain ◽

Terrain Models ◽

Mapping System ◽

Mapping Technology ◽

Images Processing

Up-to-date mapping technologies are in the middle of transition from analytical to digital. The usage of new methods and technologies implies the desire to increase mapping capability. Despite that, analytical and digital methods may be used simultaneously, thus getting more efficient results. The research objective is to present some aspects of functionality of both digital and analytical photogrammetric mapping approaches in generating 3D geodata. The experimental results show which of the two methods could lead to a more flexible mapping production in consideration of the following criteria: accuracy, flexibility, time and cost. The main result of investigations shows, that the orthophoto generation is successfully using fully automatic systems. The digital terrain models created by two technologies are almost the same due to time-consuming. Therefore more time is required for the Digital Photogrammetric System when the terrain is rougher. Despite the fact that digital photogrammetric mapping technology drastically develops, there is no doubt that analytical photogrammetry is still a significant production system for large‐scale mapping. The results demonstrate that there is not too much difference in accuracy between the analytical and the digital 14 μm pixel size images processing. The interpretation capability of experimental test area in the Digital Photogrammetric System was more complicated as it was by the analytical plotter. Two systems integrations have been foreseen. Digital terrain model obtained by the analytical plotter can be transferred to digital mapping system for orthophoto generation.

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LOD2 Building Generation Experiences and Comparisons

Journal of Applied Engineering Sciences ◽

10.2478/jaes-2018-0019 ◽

2018 ◽

Vol 8 (2) ◽

pp. 59-64

Author(s):

Iuliana Maria Pârvu ◽

F. Remondino ◽

E. Ozdemir

Keyword(s):

Knowledge Transfer ◽

Digital Terrain Model ◽

Point Clouds ◽

Surface Model ◽

Ancillary Data ◽

Terrain Model ◽

Digital Terrain ◽

Research Activities ◽

Building Models ◽

Technical Details

Abstract The VOLTA project is a RISE Marie-Curie action designed to realize Research & Innovation (R&I) among intersectoral partners to exchange knowledge, methods and workflows in the geospatial field. To accomplish its objectives, the main R&I activities of VOLTA are divided in four interlinked Work Packages with two transversal ones responsible for knowledge transfer & training as well as dissemination of the project results. The research activities and knowledge transfer are performed with a series of secondments between partners. The consortium is composed of 13 partners from academic & research institutions, industrial partners and national mapping agencies. The Romanian National Center of Cartography is part of this research project and in this article the achievements of the secondment at Bruno Kessler Foundation in Trento (Italy) are given. The main goal of the exchange was to generate level of detail - LOD2 building models in an automated manner from photogrammetric point clouds and without any ancillary data. To benchmark existing commercial solutions for the realization of LOD2 building models, we tested Building Reconstruction. This program generates LOD2 models starting from building footprints, digital terrain model (DTM) and digital surface model (DSM). The presented work examined a research and a commercial-based approach to reconstruct LOD2 building models from point clouds. The full paper will report all technical details of the work with insight analyses and comparisons.

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DEVELOPING A STRATEGY FOR PRECISE 3D MODELLING OF LARGE-SCALE SCENES FOR VR

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliii-b4-2020-567-2020 ◽

2020 ◽

Vol XLIII-B4-2020 ◽

pp. 567-574 ◽

Cited By ~ 1

Author(s):

A. El Saer ◽

C. Stentoumis ◽

I. Kalisperakis ◽

P. Nomikou

Keyword(s):

Virtual Reality ◽

Large Scale ◽

Digital Terrain Model ◽

3D Models ◽

3D Modelling ◽

Mesh Simplification ◽

Geospatial Data ◽

Terrain Model ◽

Physically Based ◽

Physically Based Rendering

Abstract. In this work, we present a methodology for precise 3D modelling and multi-source geospatial data blending for the purposes of Virtual Reality immersive and interactive experiences. We evaluate it on the volcanic island of Santorini due to its formidable geological terrain and the interest it poses for scientific and touristic purposes. The methodology developed here consists of three main steps. Initially, bathymetric and SRTM data are scaled down to match the smallest resolution of our dataset (LIDAR). Afterwards, the resulted elevations are combined based on the slope of the relief, while considering a buffer area to enforce a smoother terrain. As a final step, the orthophotos are combined with the estimated Digital Terrain Model, via applying a nearest neighbour matching schema leading to the final terrain background. In addition to this, both onshore and offshore points-of-interest were modelled via image-based 3D reconstruction and added to the virtual scene. The overall geospatial data that need to be visualized in applications demanding photo-textured hyper-realistic models pose a significant challenge. The 3D models are treated via a mesh optimization workflow, suitable for efficient and fast visualization in virtual reality engines, through mesh simplification, physically based rendering texture maps baking, and level-of-details.

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