Scale 3D Model Research Articles

Numerical simulation for heat transfer behavior of copper slag ladle under air-cooling mechanism

Copper slag ladle cooling process is divided into two stages: air-cooling and water-cooling, is one of the important processes in copper production process from copper slag flotation recovery of valuable metals. This study investigates the transient heat transfer behavior of copper slag ladle during air-cooling mechanism based on the finite-volume method. The innovative aspect of this research lies in development of a 1:1 scale 3D model of slag ladle based on industrial-scale dimensions, obtaining the relevant thermophysical parameters of copper slag by experiment, and validating simulation results against actual industrial production data. The results of study show that: (i) The temperature distribution of copper slag within slag ladle exhibits a “concentric circle” pattern with the formation of a “liquid core” zone, indicating that the temperature is significantly higher in central region compared to periphery, revealing a notable temperature gradient during the air-cooling process; (ii) The heat flux is most concentrated in the central region of slag ladle, suggesting that the heat transfer intensity is the greatest in this area, the temperature variation of copper slag in proximity to this region is the most pronounced; (iii) The cooling path of copper slag proceeds from outer layers to inner layers, with the cooling rate decreasing from fast to slow, reflecting the temperature change trend of copper slag during air-cooling, which transitions from rapid to gradual cooling. This study provides new perspectives and data support for exploring air-cooling process of copper slag ladle and contributes to the further advancement of this field.

Immersive presentations of real-world medical equipment through interactive VR environment populated with the high-fidelity 3D model of mobile MRI unit

The primary goal behind the system presented in this paper is to investigate the efficacy of using virtual reality (VR) for showcasing sizable medical equipment. Specifically, we focused on a mobile magnetic resonance imaging (MRI) scanner mounted on a truck trailer. The latter is integral to the mobile MRI setup and must be presented as part of the immersive experience. Therefore, we not only have to depict the medical apparatus but also provide the means of understanding its surroundings. This is especially important to radiologists and other medical personnel to ascertain if a given mobile medical facility fulfills their needs and wants. Furthermore, despite such MRI devices being designed for mobility, their long-distance transportation can be time-consuming, troublesome and expensive. Therefore, we can observe the need for showcasing such mobile MRI units without additional cost and burden related to transportation. To achieve this, we designed an immersive environment in which the users can interact with the real-life scale 3D model of a mobile MRI. In addition, we also verified the usability and expressiveness of our system using established heuristical approaches.

Investigation into the Construction Response of Tunnels through Fault: Model Test

The fractured zone poses a significant risk to construction safety and structure durability in tunnel engineering. However, the effect of excavation methods has not been thoroughly investigated in previous studies. This paper presents a series of 1:30 scale 3D model tests on fault tunnels under the coupling effect of different fault dip angles and construction steps. We measured and analyzed the rock mass deformation and lining structure stress to explore the influence of tunnel excavation by the CD method. The model test results were verified by numerical simulation using the prototype tunnel parameters. Our results show that steeper fault dips correspond to greater radial pressure of the surrounding rock, and pressure in both haunt positions changes more significantly than that in the vault position, while pressure in the side-wall position changes only slightly. Additionally, considerable deformation can be observed in the vault and both haunt positions, with a rock mass relaxation range of less than 1.0 D. For the lining structure stress of each point in the second excavation cycle, larger lining stress is measured in the case of a fault dip of 75° than that in cases when the fault dip equals 45° and 60°, respectively. The biggest stress is observed in the side-wall position after the mid-partition is mantled to form a closed-loop lining structure. Overall, our findings provide valuable insights into the construction response of tunnels through faults and highlight the importance of considering excavation methods in tunnel engineering.

Application of quasi-rotation surface segments in architectural prototyping

The present paper details an approach to modeling of quasi-rotation surface segments with pre-defined conditions. The desired surfaces and their segments are formed parametrically through Maple computer algebra system. Various analytical approaches to trimming of the excessive parts of quasi-rotation surfaces are indicated. Geometric modeling is performed with use of a previously developed algorithm. An example illustrating the initial stage of design of an overpass between two separate buildings is provided. The design objective contains the basic geometric parameters of the desired architectural element. Three control models were created with the same initial parameters through basic CAD software methods. All of the constructed models are thin-walled. Mechanical properties of the scale 3D models of the target element were compared in equal conditions by means of CAD software. The prototype created through the use of a quasi-rotation surface segment was the most resistant to load. The paper also features a rendered concept of a complex of three towers connected with three overpasses. The acquired results allow us to conclude that quasi-rotation is an effective method of formation of models of architectural elements.

Model Scaling in Smartphone GNSS-Aided Photogrammetry for Fragmentation Size Distribution Estimation

Fragmentation size distribution estimation is a critical process in mining operations that employ blasting. In this study, we aim to create a low-cost, efficient system for producing a scaled 3D model without the use of ground truth data, such as GCPs (Ground Control Points), for the purpose of improving fragmentation size distribution measurement using GNSS (Global Navigation Satellite System)-aided photogrammetry. However, the inherent error of GNSS data inhibits a straight-forward application in Structure-from-Motion (SfM). To overcome this, the study proposes that, by increasing the number of photos used in the SfM process, the scale error brought about by the GNSS error will proportionally decrease. Experiments indicated that constraining camera positions to locations, relative or otherwise, improved the accuracy of the generated 3D model. In further experiments, the results showed that the scale error decreased when more images from the same dataset were used. The proposed method is practical and easy to transport as it only requires a smartphone and, optionally, a separate camera. In conclusion, with some modifications to the workflow, technique, and equipment, a muckpile can be accurately recreated in scale in the digital world with the use of positional data.

Quick and Dirty (and Accurate) 3D Paleoseismic Trench Models Using Coded Scale Bars

Abstract Structure-from-motion (SfM) modeling has dramatically increased the speed of generating geometrically accurate orthophoto mosaics of paleoseismic trenches, but some aspects of this technique remain time and labor intensive. Model accuracy relies on control points to establish scale, reduce distortion, and orient 3D models. Traditional SfM methods use total station or Global Navigation Satellite System (GNSS) surveys to constrain models, but collecting control points along a vertical trench wall is often inhibited by poor line of sight to the survey sensor or limited sky view and requires many hours in the field and office. We used physical scale bars printed with coded targets to constrain SfM models of a dusty, 46-m-long trench excavation across the Teton fault (Wyoming, U.S.A.). We present a workflow for generating quick and accurate 3D SfM models and orthophoto mosaics and compare the effectiveness of using scale bar, GNSS, and total-station control in the models. Our results show that the scale bar model deviates from total station survey points by an average of 3.1 cm (maximum of 5.3 cm). In addition, the scale-bar model only deviates an average of 1.7 cm (maximum 3.5 cm) when compared to the best model alternative, the SfM model controlled by the total station survey. Scale bars eliminate several hours needed to collect and incorporate control points from total station or GNSS surveys and significantly simplify the workflow, at the cost of slightly increased 3D model and orthophoto mosaic error. Our results further suggest that trench models can be constrained with at least four physical scale bars, but using five to six physical scale bars provides redundant control for field deployment and model optimization. The scale bar method for paleoseismic trenches proves to be portable and fast, minimizes the need for specialized survey equipment, and maintains model accuracy needed for mapping trench walls.

Uncertainty Visualisation of a 3D Geological Geometry Model and Its Application in GIS-Based Mineral Resource Assessment: A Case Study in Huayuan District, Northwestern Hunan Province, China

This paper reports an application of uncertainty visualisation of a regional scale (1:50 000) 3D geological geometry model to be involved in GIS-based 3D mineral potential assessment of the Xiangxibei lead-zinc mineral concentration area in northwestern Hunan District, China. Three-dimensional (3D) geological modelling is a process of interpretation that combines a set of input measurements in geometry. Today, technology has become a necessary part of GIS-based deep prospecting. However, issues of sparse data and imperfect understanding exist in the process so that there are several uncertainties in 3D geological modelling. And these uncertainties are inevitably transmitted into the post-processing applications, such as model-based mineral resource assessment. Thus, in this paper, first, a big-data-based method was used to estimate the uncertainty of a 3D geological model; second, a group of expectations of geological geometry uncertainty were calculated and integrated into ore-bearing stratoisohypse modelling, which is one of the major favourable parameters of assessment for Lead-Zinc (Pb-Zn) deep prospectivity mapping in northwestern Hunan; and finally, prospecting targets were improved.

Efficient regional scale 3D potential field geophysical modelling to redefine the geometry of granite bodies beneath prospective, geologically complex, northwest Tasmania

In this study, a regional model that defines the three-dimensional geometry of the subsurface geology beneath the complex, prospective northwestern Tasmania has been developed. This has been achieved using a series of potential field inversions constrained by surface geology, geological sections, seismic interpretations and a newly extended petrophysical dataset. Three major episodes of granitic magmatism are preserved in Tasmania: in the Neoproterozoic, Cambrian and Devonian. Granite bodies are hence considered important indicators of mineralization for explorers in an area of challenging vegetation, topography and cover sequences. Forward modelling and property-based inversions of the pre-existing geological model show that the previously interpreted subsurface geometry is not compatible with potential field data. Four sub-regions displayed a large discrepancy between calculated and observed data. This study redefines the subsurface geometries of these sub-regions through individual geometry inversions. The density and magnetic susceptibility ranges of units are further refined through property inversions. The modified geometry of the Devonian granites in the four sub-regions may be summarized as follows: 1) the Housetop Granite is relatively thin (≤5 km thickness), whereas 2) the Heemskirk and Meredith Granites are very thick and granite extends to a shallower depth between these bodies than previously interpreted. This region between plutons is thus a more prospective region than previously thought. 3) For the first time, an intrusive body underlying the eastern part of the Rocky Cape Group has been identified. Its petrophysical properties are similar to that of a granite, and its top is interpreted at a depth of >3 km. This interpreted low density (granitic) unit may be either Neoproterozoic or Devonian. 4) A new non-magnetic, low density Cambrian granite, with a minimum burial depth of 1 km, is also modelled in 3D, within the Mount Read Volcanics, in the south of the study area. Our approach, whereby sub-regions are identified for more detailed modelling, enables new constraints to be introduced in a computationally efficient way, and has general application to refining the geometry of key structures in prospective regions.

Developing the 3D geological model for Crossrail 2, London, UK

A 3D geological model, referred to as the Project Stratigraphic Model, has been developed for Crossrail 2, a proposed £30 bn railway linking Surrey and Hertfordshire via 27 km long tunnels through London. The British Geological Survey 1:50 000 scale 3D model of the London Basin was adopted as the initial baseline. Over 1000 boreholes were collated, together with information from existing publications, such as tunnel face excavation records, to review and develop the Project Stratigraphic Model. Digital tools such as ArcGIS and Leapfrog Works facilitated the efficient development, interrogation and dissemination of the c. 40 km 2 model and helped to communicate geological uncertainty. The Project Stratigraphic Model was a key tool in identifying geological hazards along the route, designing the vertical alignment, informing early design decisions for the proposed structures and estimating third-party building foundation depths for obstruction risk assessments. Further refinement of the model will continue into future design and construction stages, including the addition of project-specific ground investigation, geotechnical parameters and construction data, and will provide an invaluable geotechnical risk management tool for the project. Thematic collection: This article is part of the Ground models in engineering geology and hydrogeology collection available at: https://www.lyellcollection.org/cc/Ground-models-in-engineering-geology-and-hydrogeology

A 3D Geological Model as a Base for the Development of a Conceptual Groundwater Scheme in the Area of the Colosseum (Rome, Italy)

Geological models are very useful tools for developing conceptual schemes owing to their capacity to optimize the management of stratigraphic information. This is particularly true in areas where archaeological heritage is exposed to hydrogeological hazards; 3D models can constitute the first step toward the construction of numerical models created to understand processes and plan mitigation actions to improve visitor safety and preserve archaeological heritage. This paper illustrates the results of a 3D hydrostratigraphic model of the site of the Colosseum in the Central Archaeological Area of Rome. In recent years, this area has experienced numerous floods caused by intense meteorological events. A new borehole survey provided the opportunity to update previous maps and cross sections and build a local scale 3D model. The resulting conceptual model was used to identify primary gaps in existing knowledge about the groundwater system and to optimize the planning of a piezometer monitoring network. Further studies can then focus on the development of groundwater numerical models to verify hypotheses regarding inflow-outflow dynamics and facilitate the optimization of water management.

Robot Manipulator Programming Interface based on Augmened Reality

The integration cost of industrial robots into small and medium sized enterprises (SMEs) is nowadays one of the main obstacles to make automated solutions profitable. The standard implemented human robot interface (HRI) in industrial robots, is complicated and time consuming even for trained technicians. A well-known trend in robotic manipulator development, known in the field of intelligent HRI, is aimed at to make automated solutions with industrial robots cost-effective. A HRI based on augmented reality (AR) is presented to cut short the programming phase during commissioning of industrial robots in the production line. The system proposed in the given article was implemented on a portable computer in accordance with an AR-Stylus using safety goggles mounted with a high-resolution camera and a wearable display. The hardware setup presented was used in an experiment to show, how the HRI's basic functions, namely intuitive robot programming by demonstration (PbD), visualisation and simulation of industrial robots program, could be implemented. A high level of encapsulating the programmer into an AR environment was achieved by configuring a camera tracking the 6D position of the AR-Stylus and a real-time projection of the 3D robot gripper model virtually substituting the AR-Stylus. In contrast to the HRI based on the conventional PbD method, this paper covers a new type of PbD called “virtual robot programming by demonstration” (vPbD). The accuracy of the HRI system in determining the position of the AR-Stylus was experimentally analysed. In a sequential robotic program, apart from visualising the endpoints and the trajectories in WD, a real scale 3D model projection of the robot gripper is aligned in real-world environment from the observer's perspective. This enables the operator to detect potential collisions of the robot gripper with the surrounding with efficacy. Further conclusions and developments pertaining to the study will be followed

ОЦЕНКА ВОЗМОЖНОСТИ НАРАБОТКИ ДЕЛЯЩИХСЯ ИЗОТОПОВ ДЛЯ РЕАКТОРОВ ДЕЛЕНИЯ В БЛАНКЕТЕ ТЕРМОЯДЕРНОГО РЕАКТОРА

Calculations for the fusion reactor were carried. The purpose this one is assessment of an opportunity to use blanket of these units for fission isotopes reproduction for fission reactors. This paper contains: - full scale 3D model, where 1/8 space part was used (symmetry), biological shielding and toroidal coil winding were included in model, model size about 5,8 m for every X,Y,Z geometry axis; - results by MCU and LUCKY-A codes of neutron fluxes, reaction rates; - reproduction coefficient for thorium-232 as relation to intensity of neutron source; - analysis of results. MCU and LUCKY-A computer codes use parallel calculation technologies to get solution transport equation.

Scaled layout recovery with wide field of view RGB-D

In this work, we propose a method that integrates depth and fisheye cameras to obtain a wide 3D scene reconstruction with scale in one single shot. The motivation of such integration is to overcome the narrow field of view in consumer RGB-D cameras and lack of depth and scale information in fisheye cameras. The hybrid camera system we use is easy to build and calibrate, and currently consumer devices with similar configuration are already available in the market. With this system, we have a portion of the scene with shared field of view that provides simultaneously color and depth. In the rest of the color image we estimate the depth by recovering the structural information of the scene. Our method finds and ranks corners in the scene combining the extraction of lines in the color image and the depth information. These corners are used to generate plausible layout hypotheses, which have real-world scale due to the usage of depth. The wide angle camera captures more information from the environment (e.g. the ceiling), which helps to overcome severe occlusions. After an automatic evaluation of the hypotheses, we obtain a scaled 3D model expanding the original depth information with the wide scene reconstruction. We show in our experiments with real images from both home-made and commercial systems that our method achieves high success ratio in different scenarios and that our hybrid camera system outperforms the single color camera set-up while additionally providing scale in one single shot.

Preservation of local high-resolution data in a regional low-resolution dataset: A ‘nested’ 3D modeling approach using an example from a Quaternary glacial stratigraphy (Ontario, Canada)

Regional scale 3D models provide insight into general unit geometries and stratigraphic relationships; however, potentially significant local scale data and unit geometries are rarely preserved. Accurate modeling of local scale unit geometries and stratigraphic relationships is important for understanding aquifer-aquitard connectivity, estimation of aquifer volume, and prediction of contaminant migration pathways; this is particularly important in previously glaciated areas because of the high degree of lithological heterogeneity and stratigraphic variation in glaciogenic deposits. This study presents a case study (Ontario, Canada) that explores the impacts of an optimized model (in which high-resolution data are preserved in local scale models as ‘golden blocks’) and non-optimized regional scale 3D models on the predicted geometries and stratigraphic relationships of coarse- and fine-grained units (lithofacies associations) within a Quaternary stratigraphy. Each of the regional scale models include high quality data (outcrop and cored borehole logs) and low quality data (water well lithology logs); however, the optimized model was constructed by seamlessly integrating the golden blocks into the regional scale model using an algorithm (producing a ‘nested’ model), whereas the non-optimized model was built using a global modeling approach. By way of comparison to unit geometries previously delineated in outcrops and surficial geology maps and hydraulic responses from pumping tests, the results of this study indicate that coarse-grained units, which host significant municipal aquifers, and fine-grained units were more realistically and accurately represented in the optimized model as a result of the nested 3D modeling approach. This case study demonstrates a relatively simple and effective method for preserving high quality data in a regional scale 3D model without sacrificing model accuracy in key areas of interest (e.g. aquifer well fields).

Application of photogrammetry to automated finishing operations

Buffing is usually the last and most important operation carried out during manufacturing processes, especially for use in applications that require strict tolerances. For objects with irregular geometry, this operation may have to be done manually. In an effort to automate the buffing process, robot simulation platforms can develop offline programs for specific geometries that are known beforehand. However, in the case of unknown geometries, it is required to first develop the CAD model before processing within simulation platforms. This can be done using either manual measurement of the object, which could be tedious, 3D scanning the object, which requires specialized expensive equipment, or the process of photogrammetry, which is cheap and readily accessible. This paper describes the use of photogrammetry to develop scale 3D models of irregular objects, which is subsequently used to generate tool paths for an industrial robot via offline programming, to be applied in finishing operations. The photogrammetry procedure involves compiling photographs of the target object from a 360° orientation, and using a photogrammetry software to generate the 3D model of the target object. This model is then used within the simulation software to develop the final output. A commercial photogrammetry software, Bentley’s ContextCapture, is used to develop the 3D models, which are then imported to RobotStudio which can generate end-effector toolpaths for buffing operations to be carried out on the scanned object, based on the contours of the model. The offline program thus obtained is to be transferred to an IRB 1410 6 DOF industrial manipulator for execution and verification.

Tidal downscaling from the open ocean to the coast: a new approach applied to the Bay of Biscay

Downscaling physical processes from a large scale to a regional scale 3D model is a recurrent issue in coastal processes studies. The choice of boundary conditions will often greatly influence the solution within the 3D circulation model. In some regions, tides play a key role in coastal dynamics and must be accurately represented.The Bay of Biscay is one of these regions, with highly energetic tides influencing coastal circulation and river plume dynamics. In this study, three strategies are tested to force with barotropic tides a 3D circulation model with a variable horizontal resolution. The tidal forcings, as well as the tidal elevations and currents resulting from the 3D simulations, are compared to tidal harmonics extracted from satellite altimetry and tidal gauges, and tidal currents harmonics obtained from ADCP data.The results show a strong improvement of the M2 solution within the 3D model with a ”tailored” tidal forcing generated on the same grid and bathymetry as the 3D configuration, compared to a global tidal atlas forcing. Tidal harmonics obtained from satellite altimetry data are particularly valuable to assess the performance of each simulation. Comparisons between sea surface height time series, a sea surface salinity database, and daily averaged 2D currents also show a better agreement with this tailored forcing.

High resolution model mesh and 3D printing of the Gaudí’s Porta del Drac

This article intends to explore the limits of scanning with the technology of 3D Laser Scanner and the 3D printing, as an approximation to its application for the survey and the study of singular elements of the architectural heritage. The case study we developed is the Porta del Drac, in the Pavelló Güell, designed by Antoni Gaudí. We divided the process in two parts, one about how to scan and optimize the survey with the Laser Scanner Technology, made with a Faro Forus3D x330 scanner. The second one, about the optimization of the survey as a high-resolution mesh to have a scaled 3D model to be printed in 3D, for the musealization of the Verdaguer House of Literature in Vil.la Joana (Barcelona), a project developed by the Museum of History of Barcelona, in tribute to Jacint Verdaguer. In the first place, we propose a methodology for the survey of this atypical model, which is of special interest for several factors: the geometric complexity in relation to the occlusions, the thickness of the metallic surfaces, the hidden internal structure partially seen from the outside, the produced noise in its interior, and the instrumental errors. These factors make the survey process complex from the data collection, having to perform several scans from different positions to cover the entire sculpture, which has a geometry composed of a variety of folds that cause occlusions. Also, the union of the positions and the average of the surfaces is of great relevance, since the elements of the sculpture are constructed by a metal plate of 2mm, therefore, the error in the union of all these many positions must be smaller than this. Moreover, optimization of the cloud has a great difficulty because of the noise created by the instrumental error as it is a metal sculpture and because of noise point clouds that are generated inside the internal folds of the wings, which are made with a welded wire mesh with little spaces between them. Finally, the added difficulty that there is an internal structure between elements of the parts of the Drac that are partially hidden and therefore cannot be recorded. Secondly, we expose the procedures performed to move from a point cloud to an optimal high-resolution mesh to be printed in 3D, adapting it to all the limitations that this printing technique entails. On the one hand, for the meshing process, a previous classification of the point cloud by pieces (wings, chains, mosaics, head …) is made and an internal structure is re-assembled to avoid floating parts. On the other hand, the selection of the 3D printing technique, in this case FDM (Fused Deposition Modelling), limits the size of the model so it needs to be cut by determined maximum dimension, and also it limits the minimum thickness of the model’s surface, that is to say, the model cannot be directly scaled to the desired size because the 2mm surfaces would be too thin to be printed. This research intends to advance the knowledge of data acquisition, optimization, modelling and 3D printing, with a case study of great complexity. A process that can be systematized and applied to other models.

Large scale three-dimensional modelling for wave and tidal energy resource and environmental impact: Methodologies for quantifying acceptable thresholds for sustainable exploitation

We describe a modelling project to estimate the potential effects of wave & tidal stream renewables on the marine environment. • Realistic generic devices to be used by those without access to the technical details available to developers are described. • Results show largely local sea bed effects at the level of the currently proposed renewables developments in our study area. • Large scale 3D modelling is critical to quantify the direct, indirect and cumulative effects of renewable energy extraction. • This is critical to comply with planning & environmental impact assessment regulations and achieve Good Environmental Status.

THREE-DIMENSIONAL ANALYSIS OF NORMAL FAULT ZONES IN KARDIA MINE, PTOLEMAIS BASIN, NW GREECE

Six normal fault zones, with throws ranging from a few meters up to 50 m, were studied within an active, open pit, lignite mine in Ptolemais. Each fault was mapped 20 times over a period of five years because at intervals of ca. 3 months working faces are taken back between 20 and 50 m exposing fresh fault outcrops for mapping.Various resolutions of photographs and structural measurements were imported into a fully georeferenced 3D structural interpretation package, resulting in aseismic scale and outcrop resolution 3D fault volume with outcrop and panoramic photographs acting as the seismic sections in equivalent seismic surveys. Low resolution 3D models for the fault system structure at mine scale and higher-resolution 3D models for the fault zone structure were produced after geological interpretation and they can be used for qualitative and quantitative analysis.

Anatomical Atlas of the Quail's Ear (Coturnix coturnix).

This study aims to enhance the anatomical knowledge of the ear of the adult quail (Coturnix coturnix) through the creation of a scaled 3D model utilizing data from micro-CT images. In addition, 17 annotated histological sections of the quail's ear are aligned to their 3D position in the model. The resulting anatomical atlas provides an intuitive insight into the 3D anatomy and can be used for medical education. The model also allows measuring anatomical structures and can thus serve as reference for the quail's auricular anatomy and as a basis to evaluate clinical diagnostic imaging results.