Artículos de revistas: "Hand-held Laser Scanner"

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Komissarov, A. V., A. V. Remizov, M. M. Shlyakhova y K. K. Yambaev. "Handheld Laser Scanner Research". Geodesy and Cartography 952, n.º 10 (20 de noviembre de 2019): 47–54. http://dx.doi.org/10.22389/0016-7126-2019-952-10-47-54.

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The authors consider hand-held laser scanners, as a new photogrammetric tool for obtaining three-dimensional models of objects. The principle of their work and the newest optical systems based on various sensors measuring the depth of space are described in detail. The method of simultaneous navigation and mapping (SLAM) used for combining single scans into point cloud is outlined. The formulated tasks and methods for performing studies of the DotProduct (USA) hand-held laser scanner DPI?8X based on a test site survey are presented. The accuracy requirements for determining the coordinates of polygon points are given. The essence of the performed experimental research of the DPI?8X scanner is described, including scanning of a test object at various scanner distances, shooting a test polygon from various scanner positions and building point cloud, repeatedly shooting the same area of the polygon to check the stability of the scanner. The data on the assessment of accuracy and analysis of research results are given. Fields of applying hand-held laser scanners, their advantages and disadvantages are identified.

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Kinsey-Henderson, Anne, Aaron Hawdon, Rebecca Bartley, Scott N. Wilkinson y Thomas Lowe. "Applying a Hand-Held Laser Scanner to Monitoring Gully Erosion: Workflow and Evaluation". Remote Sensing 13, n.º 19 (6 de octubre de 2021): 4004. http://dx.doi.org/10.3390/rs13194004.

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Detailed understanding of gully erosion processes is essential for monitoring gully remediation and requires fine-scale monitoring. Hand-held laser scanning systems (HLS) enable rapid ground-based data acquisition at centimeter precision and ranges of 10–100 m. This study quantified errors in measuring gully morphology and erosion over a four year period using two models of HLS. Reference datasets were provided by Real-Time-Kinematic (RTK) GPS and a RIEGL Terrestrial Laser Scanner (TLS). The study site was representative of linear gullies that occur extensively on hillslopes throughout Great Barrier Reef catchments, where gully erosion is the dominant source of fine sediment. The RMSE error against RTK survey points varied 0.058–0.097 m over five annual scans. HLS was found to measure annual gully headcut extension within 0.035 m of RTK. HLS was, on average, within 6% of TLS for morphological metrics of depth, area and volume. Volumetric change over a 60 m length of the gully and four years was estimated to within 23% of TLS. Errors could potentially be improved by scanning at times of year with lower ground vegetation cover. HLS provided similar levels of error and was relatively more rapid than TLS and RTK for monitoring gully morphology and change.

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Borrmann, D., S. Jörissen y A. Nüchter. "RADLER – A UNICYCLE AS A LOW-COST RADIAL LASER SCANNER". ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences V-1-2021 (17 de junio de 2021): 65–72. http://dx.doi.org/10.5194/isprs-annals-v-1-2021-65-2021.

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Abstract. In recent years a wide range of 3D multi sensor systems for various applications has been proposed. Each of them has its own benefits and limitations. This paper proposes a modified unicycle with a 2D laser profiler attached to the wheel axle, thus creating a radial 3D scanning pattern. This novel low-cost device combines the advantages of wheeled scanning equipment with those of wearable or hand-held devices. After presenting the hardware setup and the sensor integration, the results are evaluated using four test scenarios and a terrestrial laser scanner for comparison.

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James, Mike R. y John N. Quinton. "Ultra‐rapid topographic surveying for complex environments: the hand‐held mobile laser scanner (HMLS)". Earth Surface Processes and Landforms 39, n.º 1 (30 de octubre de 2013): 138–42. http://dx.doi.org/10.1002/esp.3489.

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Sofia, S., S. Sferlazza, A. Mariottini, M. Niccolini, T. Coppi, M. Miozzo, T. La Mantia y F. Maetzke. "A CASE STUDY OF THE APPLICATION OF HAND-HELD MOBILE LASER SCANNING IN THE PLANNING OF AN ITALIAN FOREST (ALPE DI CATENAIA, TUSCANY)". International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2021 (28 de junio de 2021): 763–70. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2021-763-2021.

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Abstract. Precision forestry is becoming a key sector for forest planning because it allows complex analyses of forest data to be carried out simply and economically. It contributes to the integration between technicians and operators in the sector by guaranteeing the transparency of the forest management operations (Corona et al., 2017). In the context of the progressive development of technology, we investigated the feasibility of using the hand-held mobile laser scanner (HMLS) system in different types of forest sites and comparison of the characteristics of individual trees (tree height, diameters at breast height) with traditional surveys, applied with the aim to validate the performance of the system for a future alternative methodology for forest planning thanks to the collaboration with the forestry company “Dimensione Ricerca Ecologia Ambiente Italia” (D.R.E.Am. Italia). GEOSLAM ZEB HORIZON ™ laser scanner is a hand-held mobile laser scanner containing SLAM technology that can be solved the problem of no GNSS signal or poor signal under the forest canopy making it more practical for forest investigations (Gollob et al., 2020). 15 forest sample plots are selected to reflect different stand conditions in Mediterranean forests taking into count the development stage and density of the sub-canopy vegetation, as well as the species composition in the forest stands. The aim of this study is to show the possible extrinsic circumstances that make the method fail by varying the ecological status of forest plots.

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Ni, Hong Jun, Qing Qing Chen, Lei Chen, Ming Yu Huang y Xing Xing Wang. "Modeling Design of Plastic Bottles Based on Laser Scanner and Rapid Prototyping Technology". Applied Mechanics and Materials 752-753 (abril de 2015): 1307–11. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.1307.

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Accurate surface modeling of washing liquid bottle is to get through RP technology. Point cloud data of washing liquid bottle is obtained by hand-held laser scanner and processed by Imageware software, 3D model is got by Pro/E. Rapid prototyping machine is used to print solid model. High precision model built by ABS is easily got without complex processes.

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Huang, Xia, Shunyi Zheng y Li Gui. "Automatic Measurement of Morphological Traits of Typical Leaf Samples". Sensors 21, n.º 6 (23 de marzo de 2021): 2247. http://dx.doi.org/10.3390/s21062247.

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It is still a challenging task to automatically measure plants. A novel method for automatic plant measurement based on a hand-held three-dimensional (3D) laser scanner is proposed. The objective of this method is to automatically select typical leaf samples and estimate their morphological traits from different occluded live plants. The method mainly includes data acquisition and processing. Data acquisition is to obtain the high-precision 3D mesh model of the plant that is reconstructed in real-time during data scanning by a hand-held 3D laser scanner (ZGScan 717, made in Zhongguan Automation Technology, Wuhan, China). Data processing mainly includes typical leaf sample extraction and morphological trait estimation based on a multi-level region growing segmentation method using two leaf shape models. Four scale-related traits and six corresponding scale-invariant traits can be automatically estimated. Experiments on four groups of different canopy-occluded plants are conducted. Experiment results show that for plants with different canopy occlusions, 94.02% of typical leaf samples can be scanned well and 87.61% of typical leaf samples can be automatically extracted. The automatically estimated morphological traits are correlated with the manually measured values EF (the modeling efficiency) above 0.8919 for scale-related traits and EF above 0.7434 for scale-invariant traits). It takes an average of 196.37 seconds (186.08 seconds for data scanning, 5.95 seconds for 3D plant model output, and 4.36 seconds for data processing) for a plant measurement. The robustness and low time cost of the proposed method for different canopy-occluded plants show potential applications for real-time plant measurement and high-throughput plant phenotype.

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Graciano, Alejandro, Lidia Ortega, Rafael J. Segura y Francisco R. Feito. "Digitization of religious artifacts with a structured light scanner". Virtual Archaeology Review 8, n.º 17 (26 de julio de 2017): 49. http://dx.doi.org/10.4995/var.2016.4650.

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The digitization process for religious artifacts is subject to inherent difficulties often ignored in theoretical models or pipelines. In this paper we aim to describe these problems, which are present in practical environments such as temples and churches, using white light scanners instead of other common devices or technologies such as laser scanners and photogrammetry. Our case study is based on the digitization of two religious statues belonging to a Catholic brotherhood located in a village of the Province of Jaén (Spain), one of them presenting especially several limitations. After performing the scanning process with a portable hand-held scanner, the images captured were processed until the final models were acquired. On the basis of the results obtained, we discuss the problems arising after using well-known procedures for the reconstruction of 3D models, their causes and some possible solutions to achieving a correct digitization. It should be noted that it is not the aim of this study to establish procedures for the digitization of religious artifacts, but rather to transmit the inherent constraints of these types of scenes.

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Mikita, Tomáš, Dominika Krausková, Petr Hrůza, Miloš Cibulka y Zdeněk Patočka. "Forest Road Wearing Course Damage Assessment Possibilities with Different Types of Laser Scanning Methods Including New iPhone LiDAR Scanning Apps". Forests 13, n.º 11 (26 de octubre de 2022): 1763. http://dx.doi.org/10.3390/f13111763.

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Forests make up 34.1% of the Czech Republic total area and forest roads account for nearly the same length (47,465 km) as all other roads administered by the state and its regions (55,738 km). Forest roads are not as intensively used as other roads. On the other hand, as logging trucks carry the maximum permitted load on roads and forests create a specific microclimate, forest roads are subject to rapid wear. A road wearing course is generally designed for 20 years of service and for a maximum damage level of 25% before they are supposed to be reconstructed. To ensure this life cycle is adhered to, more efficient, faster, and more flexible surface damage detection adaptable for forest environment is needed. As smartphones and their optical devices, i.e., new iPhones with LiDAR sensors, become more advanced, the option arises to perform laser scanning on road surfaces using smartphones applications. This work aimed to test this technology and its precision applicability to assessing damage to a forest wearing course and compare it with another hand-held personal laser scanner (PLShh), represented in this study by GeoSLAM ZEB Horizon scanner, and more precise terrestrial laser scanning (TLS) technology, represented in this study by Faro Focus 3D laser scanner, which have started to replace tacheometric wearing course damage surveying thanks to their greater precision. So, this study involved a comparison of three alternative laser scanning methods focused especially on these, which are implemented in new iPhones for tacheometric surveying. First, a Faro Focus 3D laser scanner was used for the TLS method. Second, the PLShh method was tested on a GeoSLAM ZEB Horizon scanner. Third, another PLShh method using an iPhone 13 Pro with applications 3D Scanner and Polycam was evaluated. If we are comparing positional height accuracy of PLShh to tacheometric surveying on reference cross position height coordinates, ZEB Horizon achieved devXY and devZ RMSE 0.108 m; 0.025 m; iPhone 13 Pro with 3D Scanner app devXY and devZ RMSE 0.185 m; 0.021 m, and with Polycam app devXY and devZ RMSE 0.31 m; 0.045. TLS achieved the best results with devXY RMSE 0.049 and devZ RMSE 0.0077. The results confirm that only the TLS scanner achieves precision values in height differences applicable for an assessment of forest road wearing course damage measurement comparable with tacheometric surveying. Surprisingly, comparing the PLShh scanners to the TLS technology, they achieved interesting results, comparing their transverse profiles and 3D objects as digital surface models (DSM) of the road to TLS in height position. In transverse profiles, ZEB Horizon achieved devZ RMSE 0.032 m; iPhone 13 Pro with 3D Scanner app devZ RMSE 0.017 m, and with Polycam app devZ RMSE 0.041 m compared to the TLS method measured using a Faro Focus 3D static laser scanner. Comparing forest road DSM to Faro Focus 3D, ZEB Horizon achieved devZ RMSE 0.028 m; iPhone 13 Pro with 3D Scanner app devZ RMSE 0.018 m and with Polycam devZ RMSE 0.041 m. These results in height differences show that the height accuracy of PLShh achieves precision, which is applicable to determining the current shape of forest road wearing course compared to the required roof shape gradient. However, further testing provided the insight that such a kind of PLShh measurement is still only possible to use for the identification of a transverse profile shape, as in length measurement the length error increases. All PLShh are able to capture the current shape of forest road cross profile, but still they cannot be used for any design or calculation of material measurement needed for wearing course repair.

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Ni, Hong Jun, Qing Qing Chen, Yi Pei, Yi Lv y Xing Xing Wang. "Design and Rapid Prototyping of S-Shape Push-Ups Frame Based on Laser Scanning". Applied Mechanics and Materials 752-753 (abril de 2015): 1401–5. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.1401.

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Model design and rapid prototyping are utilized to manufacture push-ups frame. Point cloud data can be obtained by scanning parts with hand-held laser scanner, and imported into the Imageware to process. The varied points are removed, the missing points are repaired, and then the 3D model is designed through the Pro/E. Finally, the frame model is completed by rapid prototyping printers. The manufacturing period is shorten through the way of putting two technologies in the field of manufacturing together, the production requirements are met, and the business efficiency is improved.

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Wang, Chun, Xuan Ming Zhang y Xiao Wang. "Scanning and Modeling of Large Thin-Walled Curved Surface Part". Advanced Materials Research 299-300 (julio de 2011): 810–15. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.810.

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The large sandwich structure composed of thin-walled aluminum alloy panels, and variable thickness of honeycomb or Polymethacrylimide (PMI) foam core is usually manufactured by pre-bonded forming process, that is pre-forming panels and sandwich core, and then curing adhesive them to be sandwich structure. Welding process of large thin-walled panel causes the panel surface to be irregular and have greater errors relative to the design surface. Simply CNC machining the sandwich core according to the design surface cannot guarantee an exact match sandwich core consistent with the panels. The actual topography of the panels must be scanned. It is proposed that the use of a new hand-held laser scanner, Handyscan to scan large thin-walled curved surface parts, of Geomagic software to handle the acquired point clouds and construct the surface model.

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Dunford, Adam J. y Gavin J. Macaulay. "Progress in determining southern blue whiting (Micromesistius australis) target strength: results of swimbladder modelling". ICES Journal of Marine Science 63, n.º 5 (1 de enero de 2006): 952–55. http://dx.doi.org/10.1016/j.icesjms.2005.12.011.

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Abstract Southern blue whiting target strength (TS) results from Kirchhoff modelling of swimbladder casts scanned using a hand-held 3D laser scanner are presented. The data are compared with the relationship between TS and fish length used for New Zealand stock-assessment surveys; TS = 21.8 log10(fork length) − 72.8, at 38 kHz. This relationship has its origins in the relationship used for blue whiting (Micromesistius poutassou) in the northern hemisphere, and is based on measurements on juvenile cod (Gadus morhua). The results indicate that the blue whiting relationship is not appropriate for southern blue whiting, and suggest a much steeper slope, with TS = 38 log10(fork length) − 97, at 38 kHz. Sensitivity analyses indicate that further investigations of swimbladder tilt-angle distribution and swimbladder volume are unlikely to provide evidence to support the use of the blue whiting relationship for southern blue whiting.

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Lv, Shuaishuai, Yangyang Zhu, Hai Gu, Hongjun Ni, Yue Meng y Xingxing Wang. "Structure Optimization of Microbial Fuel Cell Reactor Based on Reverse Engineering and Rapid Prototyping". MATEC Web of Conferences 166 (2018): 01003. http://dx.doi.org/10.1051/matecconf/201816601003.

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The structure of Microbial Fuel Cell (MFC) reactor was analyzed and improved by Reverse Engineering (RE) and Rapid Prototyping (RP) technology. Points cloud data of MFC reactor was accessed by hand-held laser scanner. The space surface and entity model were reconstructed accurately, and the structure of the reactor was optimized based on Imageware and Solidworks software. The reactor model was manufactured by RP machine. The optimization efficiency of MFC reactor was improved based on the combination of RE and RP, which has a good reference value for the development of MFC technology and products.

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Mestre, Sandrine, Florent Veye, Antonia Perez-Martin, Thomas Behar, Jean Triboulet, Nicolas Berron, Christophe Demattei y Isabelle Quéré. "Validation of lower limb segmental volumetry with hand-held, self-positioning three-dimensional laser scanner against water displacement". Journal of Vascular Surgery: Venous and Lymphatic Disorders 2, n.º 1 (enero de 2014): 39–45. http://dx.doi.org/10.1016/j.jvsv.2013.08.002.

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Li, Zhizhong, Chien-Chi Chang, Patrick G. Dempsey y Xiuwen Cai. "Refraction effect analysis of using a hand-held laser scanner with glass support for 3D anthropometric measurement of the hand: A theoretical study". Measurement 41, n.º 8 (octubre de 2008): 842–50. http://dx.doi.org/10.1016/j.measurement.2008.01.007.

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Toneva, Diana, Silviya Nikolova y Ivan Georgiev. "Reliability and Accuracy of Angular Measurements on Laser Scanning Created 3D Models of Dry Skulls". Journal of Anthropology 2016 (30 de agosto de 2016): 1–6. http://dx.doi.org/10.1155/2016/6218659.

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The aim of the study was to assess the accuracy and reliability of skull angles measured on 3D models created by laser scanning. Five skulls were measured through both conventional and digital measuring methods. The 3D models were created using a hand-held laser scanner Creaform VIUscan™. Seven angular characteristics were measured three times by two observers. The intra- and interobserver reliability were assessed using intraclass correlation coefficient. The differences between the digital and direct measurements were assessed using the measurement and relative errors. The intraclass correlation coefficients for digitally taken angles indicated almost perfect intra- and interobserver reliability, except for the alveolar profile angle showing moderate interobserver agreement. The overall measurement error based on the differences between digitally and directly measured angles was 0.61° and the relative error was 0.68%.

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Li, Zhizhong, Chien-Chi Chang, Patrick G. Dempsey y Xiuwen Cai. "Refraction effect analysis of using a hand-held laser scanner with glass support for 3D anthropometric measurement of the hand: Strategy comparison and application". Measurement 41, n.º 8 (octubre de 2008): 851–61. http://dx.doi.org/10.1016/j.measurement.2007.11.008.

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Kim, Chulhong, Todd N. Erpelding, Ladislav Jankovic y Lihong V. Wang. "Performance benchmarks of an array-based hand-held photoacoustic probe adapted from a clinical ultrasound system for non-invasive sentinel lymph node imaging". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, n.º 1955 (28 de noviembre de 2011): 4644–50. http://dx.doi.org/10.1098/rsta.2010.0353.

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Clinical translation of photoacoustic (PA) imaging can be facilitated by integration with commercial ultrasound (US) scanners to enable dual-modality imaging. An array-based US scanner was modified for hand-held PA imaging. The performance was benchmarked in terms of signal-to-noise ratio (SNR), axial spatial resolution and sensitivity. PA images of a tube, filled with methylene blue (MB; approx. 30 mM) and placed at various depths in chicken tissue, were acquired. A 5 cm penetration depth was achieved with an 18.6 dB SNR using a laser fluence of 3 mJ cm −2 , only one-seventh of the safety limit (20 mJ cm −2 ). An axial resolution of approximately 400 μm was maintained at all imaging depths. The PA sensitivity to MB placed 2.3 cm deep in chicken tissue was less than 100 μM. Further, after intradermal injection of MB (approx. 30 mM), a rat sentinel lymph node was clearly identified in vivo , beneath a 3.8 cm thick layer of chicken breast. The accumulated concentration of MB in the node was estimated to be approximately 7 mM. The noise-equivalent sensitivities (approx. 2 cm depth) were 17 and 85 μM, ex vivo and in vivo , respectively. These results support the use of this PA system for non-invasive mapping and image-guided needle biopsy of sentinel nodes in breast cancer patients.

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Del Perugia, Barbara, Francesca Giannetti, Gherardo Chirici y Davide Travaglini. "Influence of Scan Density on the Estimation of Single-Tree Attributes by Hand-Held Mobile Laser Scanning". Forests 10, n.º 3 (21 de marzo de 2019): 277. http://dx.doi.org/10.3390/f10030277.

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Nowadays, forest inventories are frequently carried out using a combination of field measurements and remote sensing data, often acquired with light detection and ranging (LiDAR) sensors. Several studies have investigated how three-dimensional laser scanning point clouds from different platforms can be used to acquire information traditionally collected with forest instruments, such as hypsometers and callipers to detect single-tree attributes like tree height and diameter at the breast height. The present study has tested the performances of the ZEB1 instrument, a type of hand-held mobile laser scanner, for single-tree attributes estimation in pure Castanea sativa Mill. stands cultivated for fruit production in Central Italy. In particular, the influence of walking scan path density on single-tree attributes estimation (number of trees, tree position, diameter at breast height, tree height, and crown base height) was investigated to test the efficiency of field measures. The point clouds were acquired by walking along straight lines drawn with different spacing: 10 and 15 m apart. A single-tree scan approach, which included walking with the instrument around each tree, was used as reference data. In order to evaluate the efficiency of the survey, the influence of the walking scan path was discussed in relation to the accuracy of single-tree attributes estimation, as well as the time and cost needed for data acquisition, pre-processing, and analysis. Our results show that the 10 m scan path provided the best results, with an omission error of 6%; the assessment of single-tree attributes was successful, with values of the coefficient of determination and the relative root mean square error similar to other studies. The 10 m scan path has also proved to decrease the costs by about €14 for data pre-processing, and a saving of time for data acquisition and data analysis of about 37 min compared to the reference data.

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Ts. Petleshkova, Ts Petleshkova, H. Manev, S. Sivkov, P. Timonov, A. Baltadjiev y R. Raycheva. "STUDY OF THE FACIAL MORPHOLOGY OF YOUNG BULGARIANS WITH 3D LASER SCAN". Trakia Journal of Sciences 17, Suppl. 2 (2019): 103–8. http://dx.doi.org/10.15547/tjs.2019.s.02.023.

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AIM: The aim of study was to make a cephalometric characterization of young Bulgarians using 3D laser scan. MATERIALS AND METHODS: The study included 46 males and 49 females of Bulgarian origin aged 21-30 years. Three-dimensional images were obtained using a hand-held laser scanner (FastSCAN Cobra, Polhemus Inc., Colchester VT). A set of probing points on the obtained images were used to make certain facial measurements: morphological face height, physiognomical upper facial height, lower face height. The data were statistically analyzed in SPSS 17.0. RESULTS: The facial measurements were significantly greater in males than in females. For morphological facial height most of the individuals were in very high category. For physiognomical upper facial height majority of males were in category high and females in moderate high. Regarding lower facial height most of the individuals were assessed as metriognath. CONCLUSION: The data obtained characterizing facial morphology can be used as criteria in genetic disorders diagnosis and outcome assessment in aesthetic and reconstructive surgery.

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He, Yuan, Shunyi Zheng, Fengbo Zhu y Xia Huang. "Real-Time 3D Reconstruction of Thin Surface Based on Laser Line Scanner". Sensors 20, n.º 2 (18 de enero de 2020): 534. http://dx.doi.org/10.3390/s20020534.

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The truncated signed distance field (TSDF) has been applied as a fast, accurate, and flexible geometric fusion method in 3D reconstruction of industrial products based on a hand-held laser line scanner. However, this method has some problems for the surface reconstruction of thin products. The surface mesh will collapse to the interior of the model, resulting in some topological errors, such as overlap, intersections, or gaps. Meanwhile, the existing TSDF method ensures real-time performance through significant graphics processing unit (GPU) memory usage, which limits the scale of reconstruction scene. In this work, we propose three improvements to the existing TSDF methods, including: (i) a thin surface attribution judgment method in real-time processing that solves the problem of interference between the opposite sides of the thin surface; we distinguish measurements originating from different parts of a thin surface by the angle between the surface normal and the observation line of sight; (ii) a post-processing method to automatically detect and repair the topological errors in some areas where misjudgment of thin-surface attribution may occur; (iii) a framework that integrates the central processing unit (CPU) and GPU resources to implement our 3D reconstruction approach, which ensures real-time performance and reduces GPU memory usage. The proposed results show that this method can provide more accurate 3D reconstruction of a thin surface, which is similar to the state-of-the-art laser line scanners with 0.02 mm accuracy. In terms of performance, the algorithm can guarantee a frame rate of more than 60 frames per second (FPS) with the GPU memory footprint under 500 MB. In total, the proposed method can achieve a real-time and high-precision 3D reconstruction of a thin surface.

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Chen, Jia, Xiaojun Wu, Michael Yu Wang y Xuanfu Li. "3D shape modeling using a self-developed hand-held 3D laser scanner and an efficient HT-ICP point cloud registration algorithm". Optics & Laser Technology 45 (febrero de 2013): 414–23. http://dx.doi.org/10.1016/j.optlastec.2012.06.015.

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Chambelland, Jean-Christophe, Mathieu Dassot, Boris Adam, Nicolas Donès, Philippe Balandier, André Marquier, Marc Saudreau, Gabriela Sonohat y Hervé Sinoquet. "A double-digitising method for building 3D virtual trees with non-planar leaves: application to the morphology and light-capture properties of young beech trees (Fagus sylvatica)". Functional Plant Biology 35, n.º 10 (2008): 1059. http://dx.doi.org/10.1071/fp08051.

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We developed a double-digitising method combining a hand-held electromagnetic digitizer and a non-contact 3D laser scanner. The former was used to record the positions of all leaves in a tree and the orientation angles of their lamina. The latter served to obtain the morphology of the leaves sampled in the tree. As the scanner outputs a cloud of points, software was developed to reconstruct non-planar (NP) leaves composed of triangles, and to compute numerical shape parameters: midrib curvature, torsion and transversal curvature of the lamina. The combination of both methods allowed construction of 3D virtual trees with NP leaves. The method was applied to young beech trees (Fagus sylvatica L.) from different sunlight environments (from 1 to 100% incident light) in a forest in central France. Leaf morphology responded to light availability, with a more bent shape in well-lit leaves. Light interception at the leaf scale by NP leaves decreased from 4 to 10% for shaded and sunlit leaves compared with planar leaves. At the tree scale, light interception by trees made of NP leaves decreased by 1 to 3% for 100% to 1% light, respectively.

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Riczu, Péter, János Tamás, Péter Ákos Mesterházi y Gábor Nagy. "Development of precision apple production technologies in Institute of Water and Environmental Management". Acta Agraria Debreceniensis, n.º 47 (18 de julio de 2012): 97–101. http://dx.doi.org/10.34101/actaagrar/47/2434.

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From the precision agriculture point of view, by the rapid development of the investigated technological elements – global positioning system (GPS), remote sensing (RS), global information system (GIS) – the number of services, which were not available in the past, because of their speed, complexity or price are increasing. The high accuracy high-tech instruments provide opportunity to elaborate several fruit production technologies, which aim is creating and operating water and energy safe quality fruit production systems. To evaluate these possibilities, experience was carried out in the Study and Regional Research Farm of the University of Debrecen near Pallag with the use of a GreenSeeker 505 Hand Held™ Optical Sensor Unit, and its interface the Trimble AgGPS FmX Integrated Display board computer, and a ScanStation C10 laser scanner by Leica. The results show the absolute applicability of these equipments in precision horticulture.

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Estela, A. y J. Hamacher. "A New Approach for Documentation, Conservation and Preservation of the Monolithic Statues in San Agustín as Pilot for Outdoor Cultural Heritage Documentation in Colombia". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-5 (6 de junio de 2014): 225–29. http://dx.doi.org/10.5194/isprsarchives-xl-5-225-2014.

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The "Instituto Colombiano de Antropología e Historia" (ICANH) started a new conservation project for the "San Agustín Archaeological Park" (Huila, Colombia) in 2013. The objectives of this project are the documentation, conservation, and preservation of the numerous monolithic statues mainly by integrating the use of new technologies (3D models). A first phase of the project has been completed, resulting in three-dimensional models of 66 of the monolithic sculptures in San Agustín. The methodology developed in this first phase will show the way for other heritage sites in Colombia and for subsequent phases applied to the archaeological park. The 3D data has been obtained using two types of data acquisition technology: the Mantis Vision F5 using infrared structured-light (SL) and a laser scanner based on the phase shift (PS) technology, the Z+F Imager 5010. The results show that future phases need improvement in data acquisition. Mainly the data obtained with the hand held scanner shows many lacunae. This article presents the observations during data processing on the basis of one sculpture, "Escultura 23". In conclusion, this first phase showed where to improve for the succeeding ones, for instance the detail of the meshes need to be increased if the models are to be used for detailed conservation and preservation purposes.

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Páter Riczu y János Tamás. "Topology in the fruit plantation". Acta Agraria Debreceniensis, n.º 49 (13 de noviembre de 2012): 253–57. http://dx.doi.org/10.34101/actaagrar/49/2537.

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The localization of fruit trees, the topology of the branch structure and the spatial structure of the canopy are important to plan sitespecific agro-ecological and production technology projects in an orchard. The currently used instruments and technologies – in the precision agriculture – give opportunities to obtain these informations. The examinations were carried out in the Study and Regional Research Farm of the University of Debrecen near Pallag with the use of a GreenSeeker 505 Hand Held™ Optical Sensor Unit, and its interface the Trimble AgGPS FmX Integrated Display board computer. The collected spectral data were completed with the 3D point cloud by Leica ScanStation C10 laser scanner. The laser impulse data and the vegetation index values were integrated in a unified 3D system. The integration of the two special data collection system provides new opportunities in the development of precision production technology system. The results could be directly used in phytotechnology, water management, plant protection and harvesting in orchards. Our elaborated method can supply digital high spatial accuracy guidance data for development of the automated machines, which could provide some new developmental way in the immediate future.

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Robson, S., L. MacDonald y B. Sargeant. "METROLOGY ENABLED REFLECTION TRANSFORMATION IMAGING TO RECONSTRUCT LOCAL DETAIL IN MANUFACTURED SURFACES". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2020 (12 de agosto de 2020): 797–804. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2020-797-2020.

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Abstract. Understanding the performance of large high performance manufactured structures can require highly accurate dimensional measurement across large volumes with the often conflicting capability to record critical parts of the structure in fine detail. Examples include turbine blades, aircraft wings and off-site manufactured modular structures assembled on-site for city, energy and transport infrastructure. Established large-volume industrial metrology systems such as laser trackers and photogrammetry partially meet the need through the measurement of targets and reflectors, but are limited in capability to record high density local detail needed to capture the finest manufactured features. Whilst large-volume surface sensing is possible with laser radar, photogrammetric pattern projection and contact probing for example, the detail required at a local level typically demands local sensing which generally takes the form of a tracked sensor such as a triangulation laser scanner or hand held touch probe. Local sensing systems face challenges where surfaces have fine detail of similar magnitude to the local sensing system sampling capability and particularly for optical sensors where the light reflected back to the sensor by the surface includes specular reflections compounded by local geometry. This paper investigates how Reflection Transformation Imaging (RTI) with a dome camera and lighting system might be calibrated, characterised and tracked as an alternative technology that is more robust to material surface properties and capable of very fine surface detail capture. Laboratory results demonstrate the capability to characterise and locate the dome to sub-millimetric accuracy within a large-volume tracked space to achieve local surface sampling at the 30 μm × 30 μm level. A method utilising sparse touch probe points to seed conversion of low and high frequency normal maps into a common 3D surface is explored with local agreement with laser tracker surface probe check points to the order of 30 μm.

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Camarretta, Nicolò, Peter A. Harrison, Arko Lucieer, Brad M. Potts, Neil Davidson y Mark Hunt. "Handheld Laser Scanning Detects Spatiotemporal Differences in the Development of Structural Traits among Species in Restoration Plantings". Remote Sensing 13, n.º 9 (28 de abril de 2021): 1706. http://dx.doi.org/10.3390/rs13091706.

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A major challenge in ecological restoration is assessing the success of restoration plantings in producing habitats that provide the desired ecosystem functions and services. Forest structural complexity and biomass accumulation are key measures used to monitor restoration success and are important factors determining animal habitat availability and carbon sequestration. Monitoring their development through time using traditional field measurements can be costly and impractical, particularly at the landscape-scale, which is a common requirement in ecological restoration. We explored the application of proximal sensing technology as an alternative to traditional field surveys to capture the development of key forest structural traits in a restoration planting in the Midlands of Tasmania, Australia. We report the use of a hand-held laser scanner (ZEB1) to measure annual changes in structural traits at the tree-level, in a mixed species common-garden experiment from seven- to nine-years after planting. Using very dense point clouds, we derived estimates of multiple structural traits, including above ground biomass, tree height, stem diameter, crown dimensions, and crown properties. We detected annual increases in most LiDAR-derived traits, with individual crowns becoming increasingly interconnected. Time by species interaction were detected, and were associated with differences in productivity between species. We show the potential for remote sensing technology to monitor temporal changes in forest structural traits, as well as to provide base-line measures from which to assess the restoration trajectory towards a desired state.

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Shi, Qiang, Hanping Mao y Xianping Guan. "Numerical Simulation and Experimental Verification of the Deposition Concentration of an Unmanned Aerial Vehicle". Applied Engineering in Agriculture 35, n.º 3 (2019): 367–76. http://dx.doi.org/10.13031/aea.13221.

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Abstract. To analyze the droplet deposition under the influence of the flow field of an unmanned aerial vehicle (UAV), a hand-held three-dimensional (3D) laser scanner was used to scan 3D images of the UAV. Fluent software was used to simulate the motion characteristics of droplets and flow fields under the conditions of a flight speed of 3 m/s and an altitude of 1.5 m. The results indicated that the ground deposition concentration in the nonrotor flow field was high, the spray field width was 2.6 m, and the droplet deposition concentration was 50 to 200 ug/cm2. Under the influence of the rotor flow field, the widest deposition range of droplets reached 12.8 m. Notably, the droplet deposition uniformity worsened, and the concentration range of the droplet deposition was 0 to 500 ug/cm2. With the downward development of the downwash flow field, the overall velocity of the flow field gradually decreased, and the influence interval of the flow field gradually expanded. In this article, the droplet concentration was verified under simulated working conditions by a field experiment, thereby demonstrating the reliability of the numerical simulation results. This research could provide a basis for determining optimal UAV operating parameters, reducing the drift of droplets and increasing the utilization rate of pesticides. Keywords: Unmanned aerial vehicle (UAV), Aerial application, Downwash flow field, Droplet deposition, Simulation analysis.

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30

Wernke, Alena y Sascha Gentes. "Development of a novel tool for automation of the contamination measurement". Safety of Nuclear Waste Disposal 1 (10 de noviembre de 2021): 29–30. http://dx.doi.org/10.5194/sand-1-29-2021.

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Abstract. Considering that about 100 000 m2 of wall area per nuclear facility must be decontaminated (Hübner et al., 2017), the automation of mechanical decontamination work offers high potential to support people in performing their work and reduce errors in the decommissioning process. Furthermore, the exposure potential for people in contaminated environments is reduced and they are protected from health hazards (Petereit et al., 2019). In the ROBDEKON project, a competence center is being established in Germany to develop practical robotic systems for decontamination work in hazardous environments. To this end, four research institutions are working with industrial partners on the development of (partially) autonomous robotic systems for the decommissioning and decontamination of nuclear facilities, the handling of waste, and the remediation of landfills and contaminated sites (Petereit et al., 2019). At the Institute for Technology and Management in Construction (KIT-TMB), the focus is on development of an automated solution for the (clearance) measurement of near-surface contaminations. A mobile elevating working platform is used as the robotic platform with a contamination array as the tool. The array measures the surface activity on the wall areas and verifies compliance with the thresholds. The contamination array is based on two sensor concepts: measurement and localization. Up to four hand-held contamination-measuring devices are attached to the array to parallelize the measurement. In order to avoid damaging the sensitive detector window foil of the contamination probes, the wall surface to be measured is first examined for imperfections with the help of a laser scanner. For localization of the array, up to four laser sensors are used for distance measurements. Measurement results are automatically saved after each measurement in a table specific to the measurement method and are available to users for documentation purposes at any time. In the further course of the project, the measurement results depending on the radiation level will be overlaid with a geometric 3D environment mapping.

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Chen, Guodong, Xinyu Sun, Wenbo Yu y Hao Wang. "Analysis Model of the Relationship between Public Spatial Forms in Traditional Villages and Scenic Beauty Preference Based on LiDAR Point Cloud Data". Land 11, n.º 8 (24 de julio de 2022): 1133. http://dx.doi.org/10.3390/land11081133.

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Traditional villages are historically, culturally, scientifically and aesthetically valuable, and a beautiful landscape is the primary embodiment of a traditional village environment. Urbanization and modernization have had a great impact on village landscapes. As an important aspect of traditional village landscapes, creating beautiful public spaces is an effective way to attract tourists and improve the well-being of residents. Landscape aesthetic activities are the result of the interaction between landscape objects and aesthetic subjects. Research on the relationship between the form of traditional village public spaces and subjective aesthetic preferences has long been neglected. This research examined 31 public spaces in traditional villages in the Dongshan and Xishan areas in Lake Taihu, Suzhou. An index system of public spatial forms in traditional villages was created, basic data of spatial forms were collected using a hand-held 3D laser scanner, and the value of the spatial forms index was calculated using R language. The scenic beauty estimation (SBE) method was improved, with the estimation of the beauty of the scenic environment based on VR panorama rather than traditional photo media. Parameter screening was performed using correlation analysis and full subset regression analysis, and four models were used to fit the SBE scores and grades. The results show that the majority of public spaces had lower than average SBE scores, and the four key indicators of average contour upper height, solid-space ratio, vegetation cover, and comprehensive closure predicted SBE. In addition, the linear model (R2 = 0.332, RMSE = 64.774) had the most accurate SBE level prediction and the stochastic forest model (R2 = 0.405, RMSE = 63.311) was better at predicting specific SBE scores. The model provides managers, designers, and researchers with a method for the quantitative evaluation of visual landscape preferences and quantitative landscape spatial forms and provides a reference for the protection and renewal of traditional village landscapes.

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EASTMAN, JAY M. y ANNA M. QUINN. "Advanced Technology in Laser-Based Hand-Held Bar Code SCANNERS". Optics and Photonics News 3, n.º 9 (1 de septiembre de 1992): 25. http://dx.doi.org/10.1364/opn.3.9.000025.

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Ji, Feng, Yuchuan Shi, Lei Wang, Xiao He, Shengshan Hou, Wenkai Feng y Changjiang Liu. "Experimental study of the shear strength criterion of rock structural plane based on three-dimensional surface description". REVIEWS ON ADVANCED MATERIALS SCIENCE 61, n.º 1 (1 de enero de 2022): 673–86. http://dx.doi.org/10.1515/rams-2022-0045.

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Abstract The failure of rock mass is mainly due to the failure of the structural plane, which is an important factor to reduce the mechanical properties and stability of rock mass. The shear strength of rock mass is one of the parameters for the stability calculation of large-scale rock mass engineering. The shear strength of a rock structural plane is strongly influenced by surface morphology. Considerable research has been conducted regarding the correlation between two-dimensional structural plane morphology and shear strength. However, quantitative research on three-dimensional (3D) morphology is relatively limited. In this study, 3D printing technology was used to create molds. Using cement and sand as the main materials, additives such as early strength and water-reducing agents were added, and test samples of irregular surface topography were created. The 3D roughness was quantified by formula calculation. Using a ZScanner® 800 hand-held 3D laser scanner to perform scanning on the structural surface, the parameter curve was analysed by generating 3D coordinate information and a 3D image of the fracture surface, and the quantitative parameter M p 3 D {M}_{\text{p}}^{3\text{D}} describing the 3D morphology of the structural surface was constructed. The change rule of R p 3 D {R}_{\text{p}}^{3\text{D}} and joint roughness coefficient (JRC) were analysed under different scanning resolutions, Δ(r), the scanning precision was suggested, and the functional relationship between JRC and M p 3 D {M}_{\text{p}}^{3\text{D}} was established. Finally, a formula for shear strength parameters considering the 3D characteristics of a structural plane surface was established. The model validation results show that the experimental data were within the 95% confidence band of the model curve, the average error of the shear strength was 10.4%, the errors of friction angle and cohesion, C, were 3.4 and 9.4%, and the reliability was fine.

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Bleier, M. y A. Nüchter. "LOW-COST 3D LASER SCANNING IN AIR ORWATER USING SELF-CALIBRATING STRUCTURED LIGHT". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W3 (23 de febrero de 2017): 105–12. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w3-105-2017.

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In-situ calibration of structured light scanners in underwater environments is time-consuming and complicated. This paper presents a self-calibrating line laser scanning system, which enables the creation of dense 3D models with a single fixed camera and a freely moving hand-held cross line laser projector. The proposed approach exploits geometric constraints, such as coplanarities, to recover the depth information and is applicable without any prior knowledge of the position and orientation of the laser projector. By employing an off-the-shelf underwater camera and a waterproof housing with high power line lasers an affordable 3D scanning solution can be built. In experiments the performance of the proposed technique is studied and compared with 3D reconstruction using explicit calibration. We demonstrate that the scanning system can be applied to above-the-water as well as underwater scenes.

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35

Hu, Shaoxing, Shen Xiao, Aiwu Zhang, Yiming Deng y Bingke Wang. "Continuous-Time Laser Frames Associating and Mapping via Multilayer Optimization". Sensors 21, n.º 1 (25 de diciembre de 2020): 97. http://dx.doi.org/10.3390/s21010097.

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To achieve the ability of associating continuous-time laser frames is of vital importance but challenging for hand-held or backpack simultaneous localization and mapping (SLAM). In this study, the complex associating and mapping problem is investigated and modeled as a multilayer optimization problem to realize low drift localization and point cloud map reconstruction without the assistance of the GNSS/INS navigation systems. 3D point clouds are aligned among consecutive frames, submaps, and closed-loop frames using the normal distributions transform (NDT) algorithm and the iterative closest point (ICP) algorithm. The ground points are extracted automatically, while the non-ground points are automatically segmented to different point clusters with some noise point clusters omitted before 3D point clouds are aligned. Through the three levels of interframe association, submap matching and closed-loop optimization, the continuous-time laser frames can be accurately associated to guarantee the consistency of 3D point cloud map. Finally, the proposed method was evaluated in different scenarios, the experimental results showed that the proposed method could not only achieve accurate mapping even in the complex scenes, but also successfully handle sparse laser frames well, which is critical for the scanners such as the new Velodyne VLP-16 scanner’s performance.

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36

Lovas, T., K. Hadzijanisz, V. Papp y A. J. Somogyi. "INDOOR BUILDING SURVEY ASSESSMENT". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B1-2020 (6 de agosto de 2020): 251–57. http://dx.doi.org/10.5194/isprs-archives-xliii-b1-2020-251-2020.

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Abstract. There are multiple emerging technologies, devices and integrated equipment to support indoor mapping. The two main categories are the wearable/portable (e.g. hand-held or backpack devices) and the trolley based devices. The most widely used sensors of the integrated systems are the laser scanners (usually profile scanners), camera(s) and the IMU unit. Compared to outdoor mobile mapping systems the main difference is the lack of GNSS signals; localization is usually supported by SLAM (Simultaneous Localization and Mapping) technology, using Kalman-filtering. Current paper discusses the assessment of the potential of trolley-based indoor mobile mapping systems (MMS) by surveying a building part by multiple technologies. Besides conventional land surveying measurements, terrestrial lasers scanning and a backpack-based mobile survey have been carried out. The analysis included cloud-to-cloud comparison as well as CAD-based evaluation focusing on the geometric accuracy of the point clouds. The paper also presents the surveying workflow; on its resource-needs and potential application fields. The paper discusses the data acquisition technologies and procedures and the different quality assessment methods and results. Since an experimental survey was conducted with a backpack-based unit in the same study area, the paper gives a brief overview on how the two different mobile mapping technologies can be applied indoor, and presents the main differences, advantages and drawbacks.

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Guarnieri, A., F. Fissore, A. Masiero, A. Di Donna, U. Coppa y A. Vettore. "FROM SURVEY TO FEM ANALYSIS FOR DOCUMENTATION OF BUILT HERITAGE: THE CASE STUDY OF VILLA REVEDIN-BOLASCO". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-5/W1 (16 de mayo de 2017): 527–33. http://dx.doi.org/10.5194/isprs-archives-xlii-5-w1-527-2017.

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In the last decade advances in the fields of close-range photogrammetry, terrestrial laser scanning (TLS) and computer vision (CV) have enabled to collect different kind of information about a Cultural Heritage objects and to carry out highly accurate 3D models. Additionally, the integration between laser scanning technology and Finite Element Analysis (FEA) is gaining particular interest in recent years for structural analysis of built heritage, since the increasing computational capabilities allow to manipulate large datasets. In this note we illustrate the approach adopted for surveying, 3D modeling and structural analysis of Villa Revedin-Bolasco, a magnificent historical building located in the small walled town of Castelfranco Veneto, in northern Italy. In 2012 CIRGEO was charged by the University of Padova to carry out a survey of the Villa and Park, as preliminary step for subsequent restoration works. The inner geometry of the Villa was captured with two Leica Disto D3a BT hand-held laser meters, while the outer walls of the building were surveyed with a Leica C10 and a Faro Focus 3D 120 terrestrial laser scanners. Ancillary GNSS measurements were also collected for 3D laser model georeferencing. A solid model was then generated from the laser global point cloud in Rhinoceros software, and portion of it was used for simulation in a Finite Element Analysis (FEA). In the paper we discuss in detail all the steps and challenges addressed and solutions adopted concerning the survey, solid modeling and FEA from laser scanning data of the historical complex of Villa Revedin-Bolasco.

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Pu, Xinming, Shu Gan, Xiping Yuan y Raobo Li. "Feature Analysis of Scanning Point Cloud of Structure and Research on Hole Repair Technology Considering Space-Ground Multi-Source 3D Data Acquisition". Sensors 22, n.º 24 (8 de diciembre de 2022): 9627. http://dx.doi.org/10.3390/s22249627.

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As one of the best means of obtaining the geometry information of special shaped structures, point cloud data acquisition can be achieved by laser scanning or photogrammetry. However, there are some differences in the quantity, quality, and information type of point clouds obtained by different methods when collecting point clouds of the same structure, due to differences in sensor mechanisms and collection paths. Thus, this study aimed to combine the complementary advantages of multi-source point cloud data and provide the high-quality basic data required for structure measurement and modeling. Specifically, low-altitude photogrammetry technologies such as hand-held laser scanners (HLS), terrestrial laser scanners (TLS), and unmanned aerial systems (UAS) were adopted to collect point cloud data of the same special-shaped structure in different paths. The advantages and disadvantages of different point cloud acquisition methods of special-shaped structures were analyzed from the perspective of the point cloud acquisition mechanism of different sensors, point cloud data integrity, and single-point geometric characteristics of the point cloud. Additionally, a point cloud void repair technology based on the TLS point cloud was proposed according to the analysis results. Under the premise of unifying the spatial position relationship of the three point clouds, the M3C2 distance algorithm was performed to extract the point clouds with significant spatial position differences in the same area of the structure from the three point clouds. Meanwhile, the single-point geometric feature differences of the multi-source point cloud in the area with the same neighborhood radius was calculated. With the kernel density distribution of the feature difference, the feature points filtered from the HLS point cloud and the TLS point cloud were fused to enrich the number of feature points in the TLS point cloud. In addition, the TLS point cloud voids were located by raster projection, and the point clouds within the void range were extracted, or the closest points were retrieved from the other two heterologous point clouds, to repair the top surface and façade voids of the TLS point cloud. Finally, high-quality basic point cloud data of the special-shaped structure were generated.

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39

Holland, D. A., C. Pook, D. Capstick y A. Hemmings. "THE TOPOGRAPHIC DATA DELUGE – COLLECTING AND MAINTAINING DATA IN A 21ST CENTURY MAPPING AGENCY". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B4 (14 de junio de 2016): 727–31. http://dx.doi.org/10.5194/isprs-archives-xli-b4-727-2016.

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In the last few years, the number of sensors and data collection systems available to a mapping agency has grown considerably. In the field, in addition to total stations measuring position, angles and distances, the surveyor can choose from hand-held GPS devices, multi-lens imaging systems or laser scanners, which may be integrated with a laptop or tablet to capture topographic data directly in the field. These systems are joined by mobile mapping solutions, mounted on large or small vehicles, or sometimes even on a backpack carried by a surveyor walking around a site. Such systems allow the raw data to be collected rapidly in the field, while the interpretation of the data can be performed back in the office at a later date. In the air, large format digital cameras and airborne lidar sensors are being augmented with oblique camera systems, taking multiple views at each camera position and being used to create more realistic 3D city models. Lower down in the atmosphere, Unmanned Aerial Vehicles (or Remotely Piloted Aircraft Systems) have suddenly become ubiquitous. Hundreds of small companies have sprung up, providing images from UAVs using ever more capable consumer cameras. It is now easy to buy a 42 megapixel camera off the shelf at the local camera shop, and Canon recently announced that they are developing a 250 megapixel sensor for the consumer market. While these sensors may not yet rival the metric cameras used by today’s photogrammetrists, the rapid developments in sensor technology could eventually lead to the commoditization of high-resolution camera systems. With data streaming in from so many sources, the main issue for a mapping agency is how to interpret, store and update the data in such a way as to enable the creation and maintenance of the end product. This might be a topographic map, ortho-image or a digital surface model today, but soon it is just as likely to be a 3D point cloud, textured 3D mesh, 3D city model, or Building Information Model (BIM) with all the data interpretation and modelling that entails. In this paper, we describe research/investigations into the developing technologies and outline the findings for a National Mapping Agency (NMA). We also look at the challenges that these new data collection systems will bring to an NMA, and suggest ways that we may work to meet these challenges and deliver the products desired by our users.

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40

Holland, D. A., C. Pook, D. Capstick y A. Hemmings. "THE TOPOGRAPHIC DATA DELUGE – COLLECTING AND MAINTAINING DATA IN A 21ST CENTURY MAPPING AGENCY". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B4 (14 de junio de 2016): 727–31. http://dx.doi.org/10.5194/isprsarchives-xli-b4-727-2016.

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In the last few years, the number of sensors and data collection systems available to a mapping agency has grown considerably. In the field, in addition to total stations measuring position, angles and distances, the surveyor can choose from hand-held GPS devices, multi-lens imaging systems or laser scanners, which may be integrated with a laptop or tablet to capture topographic data directly in the field. These systems are joined by mobile mapping solutions, mounted on large or small vehicles, or sometimes even on a backpack carried by a surveyor walking around a site. Such systems allow the raw data to be collected rapidly in the field, while the interpretation of the data can be performed back in the office at a later date. In the air, large format digital cameras and airborne lidar sensors are being augmented with oblique camera systems, taking multiple views at each camera position and being used to create more realistic 3D city models. Lower down in the atmosphere, Unmanned Aerial Vehicles (or Remotely Piloted Aircraft Systems) have suddenly become ubiquitous. Hundreds of small companies have sprung up, providing images from UAVs using ever more capable consumer cameras. It is now easy to buy a 42 megapixel camera off the shelf at the local camera shop, and Canon recently announced that they are developing a 250 megapixel sensor for the consumer market. While these sensors may not yet rival the metric cameras used by today’s photogrammetrists, the rapid developments in sensor technology could eventually lead to the commoditization of high-resolution camera systems. With data streaming in from so many sources, the main issue for a mapping agency is how to interpret, store and update the data in such a way as to enable the creation and maintenance of the end product. This might be a topographic map, ortho-image or a digital surface model today, but soon it is just as likely to be a 3D point cloud, textured 3D mesh, 3D city model, or Building Information Model (BIM) with all the data interpretation and modelling that entails. In this paper, we describe research/investigations into the developing technologies and outline the findings for a National Mapping Agency (NMA). We also look at the challenges that these new data collection systems will bring to an NMA, and suggest ways that we may work to meet these challenges and deliver the products desired by our users.

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41

Puttkamer, E. von, H. Hamfeld y E. Dieterich. "3D-Scans von einem handgeführten Laser-Scanner (3D-Pictures from a Hand Held Scanner)". tm Technisches Messen 68, n.º 12/2001 (enero de 2001). http://dx.doi.org/10.1524/teme.2001.68.12.570.

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42

Timonov, Pavel, Stefan Sivkov, Tsvetanka Petleshkova, Antoaneta Fusova, Dobrinka Radoinova y Emilia Karaslavova. "Methods for Quantitative Assessment of Femoral Antroposcopic Landmarks Using Hand‑held Laser Scanner". Proceeding of the Bulgarian Academy of Sciences 66, n.º 6 (2013). http://dx.doi.org/10.7546/cr-2013-66-6-13101331-16.

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43

Rastegar, J., H. Soroff y R. T. Murray. "Development of an Automated Laser Debridement System for Cutaneous Injuries". Journal of Medical Devices 2, n.º 2 (1 de junio de 2008). http://dx.doi.org/10.1115/1.2932441.

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The initial step in the repair of a thermal or chemical burn is wound debridement, the removal of the dead skin covering the burn. Afterwards, the exposed wound is covered with a viable biological dressing, the scabs re-form and the process must be repeated until the wound is fully healed. Of the various methods of wound debridement, surgical excision is the most popular. The process uses stainless steel cutting blades mounted on different types of handles which have built-in adjustments for controlling the depth of the excision. The main problems with this treatment method are excessive bleeding and lack of high-precision control of the cutting depth. Recent advances have been made in healing treatments for thermal and chemical burns using a variety of techniques to debride damaged tissue, including the use of medical lasers, such as CO2 and Er:YAG lasers. Excision using laser beams has been shown to be associated with significantly reduced morbidity, since the amount of blood lost during debridement is significantly reduced because the depth of treatment is more precise and the process has a cauterization cycle built-in. One drawback to the available laser systems is that they all require the surgeon to move a hand piece over the damaged area. This process requires great operator skill and is time consuming for an injury with a large surface area. Small hand held scanners attached to the end of articulated arms have mitigated this drawback to some extent, but the scanned areas are relatively small and the surgeon still needs to move the scanner head over larger injuries. This project describes the development of an automated, 3D vision guided laser debridement system with a large maximum working area for efficiently treating injuries with large areas or a multitude of smaller injuries distributed over a large area. This system is designed to be fail-safe, and performs precise debridement automatically and quickly with minimal surgeon involvement.

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44

Cau, Nicola y Stefano Corna. "Circumferential versus Hand-held Laser Scanner Method for the Evaluation of Lower Limb Volumes in Normal-weight and Obese Subjects". Journal of Novel Physiotherapies 6, n.º 4 (2016). http://dx.doi.org/10.4172/2165-7025.1000303.

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45

"Low Cost Handheld 3D Scanning for Egyptian Architectural Artifacts Acquisition". International Journal of Innovative Technology and Exploring Engineering 9, n.º 8 (10 de junio de 2020): 195–200. http://dx.doi.org/10.35940/ijitee.h6268.069820.

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Surface reconstruction of objects using photogrammetry and terrestrial laser scanning systems (TLS) has been a topic for research for many decades, especially for culture heritage data recording. Recently, many advances into these systems are now available in the market, which give the availability of collecting a huge number of geo-referenced 3-D points covering any object surface. Due to speed and efficiency of data acquisition by means of terrestrial laser scanners, researchers and designers can select the reliable technique, depending on their application, that can be complete to give good results for the complex surfaces such as heritage objects. As Grand Egyptian Museum (GEM), located nearby the Giza Pyramids, is set to open by 2020, which considered as the largest museum from its type all over the world, with a huge area covered about a half million m2 . GEM is proposed to be a unique museum all over the world for presenting a huge number from old history Egyptian artifacts. Consequently, there is a vital need for building a huge digital database containing complete information for this large number of artifacts. Mobile applications are presently at the primacy of documenting historical and archaeological sites. The current paper examine the methodological framework adopted for one high copy of Pharaonic artifacts, namely Offering Carrier, using hand held laser scanning and convert the results to a mobile application.

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