A LOW-COST AND PORTABLE SYSTEM FOR 3D RECONSTRUCTION OF TEXTURE-LESS OBJECTS

The optical methods for 3D modelling of objects can be classified into two categories including image-based and range-based methods. Structure from Motion is one of the image-based methods implemented in commercial software. In this paper, a low-cost and portable system for 3D modelling of texture-less objects is proposed. This system includes a rotating table designed and developed by using a stepper motor and a very light rotation plate. The system also has eight laser light sources with very dense and strong beams which provide a relatively appropriate pattern on texture-less objects. In this system, regarding to the step of stepper motor, images are semi automatically taken by a camera. The images can be used in structure from motion procedures implemented in Agisoft software.To evaluate the performance of the system, two dark objects were used. The point clouds of these objects were obtained by spraying a light powders on the objects and exploiting a GOM laser scanner. Then these objects were placed on the proposed turntable. Several convergent images were taken from each object while the laser light sources were projecting the pattern on the objects. Afterward, the images were imported in VisualSFM as a fully automatic software package for generating an accurate and complete point cloud. Finally, the obtained point clouds were compared to the point clouds generated by the GOM laser scanner. The results showed the ability of the proposed system to produce a complete 3D model from texture-less objects.

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Structure from motion (SfM) photogrammetry as alternative to laser scanning for 3D modelling of historical monuments

Open Science Journal ◽

10.23954/osj.v5i2.2327 ◽

2020 ◽

Vol 5 (2) ◽

Cited By ~ 1

Author(s):

Omar Al Khalil

Keyword(s):

Structure From Motion ◽

Laser Scanning ◽

Low Cost ◽

Laser Scanner ◽

Digital Camera ◽

Point Clouds ◽

3D Modelling ◽

3D Point Clouds ◽

Historical Monuments ◽

Culture Heritage

During the past few years, new developments have occurred in the field of 3D photogrammetric modeling of culture heritage. One of these developments is the expansion of 3D photogrammetric modeling open-source software, such as VisualSfM, and cost-effective licensed software, such as Agisoft Metashape into the practical and affordable world. This type of SfM (Structure from Motion) software offers the world of 3D modelling of culture heritage a powerful tool for documentation and visualization. On the other hand, low-cost cameras are now available on the market. These cameras are characterized by high resolution and good quality lens, which makes them suitable for photogrammetric modelling. This paper reports on the results of the application of a SfM photogrammetry system in the 3D modelling of Safita Tower, a medieval structure in Safita, north-western Syria. The applied photogrammetric system consists of the Nikon Coolpix P100 10 MP digital camera and the commercial software Agisoft Metashape. The resulted 3D point clouds were compared with an available dense point cloud acquired by a laser scanner. This comparison proved that the low-cost SfM photogrammetry is an accurate methodology to 3D modeling historical monuments.

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To 3D or Not 3D: Choosing a Photogrammetry Workflow for Cultural Heritage Groups

Heritage ◽

10.3390/heritage2030112 ◽

2019 ◽

Vol 2 (3) ◽

pp. 1835-1851 ◽

Cited By ~ 14

Author(s):

Hafizur Rahaman ◽

Erik Champion

Keyword(s):

Low Cost ◽

Laser Scanner ◽

Ground Truth ◽

Point Clouds ◽

3D Models ◽

3D Modelling ◽

Quality Data ◽

Average Deviation ◽

Ground Truth Data ◽

Software Application

The 3D reconstruction of real-world heritage objects using either a laser scanner or 3D modelling software is typically expensive and requires a high level of expertise. Image-based 3D modelling software, on the other hand, offers a cheaper alternative, which can handle this task with relative ease. There also exists free and open source (FOSS) software, with the potential to deliver quality data for heritage documentation purposes. However, contemporary academic discourse seldom presents survey-based feature lists or a critical inspection of potential production pipelines, nor typically provides direction and guidance for non-experts who are interested in learning, developing and sharing 3D content on a restricted budget. To address the above issues, a set of FOSS were studied based on their offered features, workflow, 3D processing time and accuracy. Two datasets have been used to compare and evaluate the FOSS applications based on the point clouds they produced. The average deviation to ground truth data produced by a commercial software application (Metashape, formerly called PhotoScan) was used and measured with CloudCompare software. 3D reconstructions generated from FOSS produce promising results, with significant accuracy, and are easy to use. We believe this investigation will help non-expert users to understand the photogrammetry and select the most suitable software for producing image-based 3D models at low cost for visualisation and presentation purposes.

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Estimating tree stem diameters and volume from smartphone photogrammetric point clouds

Forestry An International Journal of Forest Research ◽

10.1093/forestry/cpz067 ◽

2019 ◽

Vol 93 (3) ◽

pp. 411-429 ◽

Cited By ~ 3

Author(s):

Maria Immacolata Marzulli ◽

Pasi Raumonen ◽

Roberto Greco ◽

Manuela Persia ◽

Patrizia Tartarino

Keyword(s):

Low Cost ◽

Three Dimensional ◽

Laser Scanner ◽

Point Clouds ◽

Stem Volume ◽

Forest Plot ◽

3D Point Clouds ◽

Dense Point ◽

Minimum Number ◽

Scale Point

Abstract Methods for the three-dimensional (3D) reconstruction of forest trees have been suggested for data from active and passive sensors. Laser scanner technologies have become popular in the last few years, despite their high costs. Since the improvements in photogrammetric algorithms (e.g. structure from motion—SfM), photographs have become a new low-cost source of 3D point clouds. In this study, we use images captured by a smartphone camera to calculate dense point clouds of a forest plot using SfM. Eighteen point clouds were produced by changing the densification parameters (Image scale, Point density, Minimum number of matches) in order to investigate their influence on the quality of the point clouds produced. In order to estimate diameter at breast height (d.b.h.) and stem volumes, we developed an automatic method that extracts the stems from the point cloud and then models them with cylinders. The results show that Image scale is the most influential parameter in terms of identifying and extracting trees from the point clouds. The best performance with cylinder modelling from point clouds compared to field data had an RMSE of 1.9 cm and 0.094 m3, for d.b.h. and volume, respectively. Thus, for forest management and planning purposes, it is possible to use our photogrammetric and modelling methods to measure d.b.h., stem volume and possibly other forest inventory metrics, rapidly and without felling trees. The proposed methodology significantly reduces working time in the field, using ‘non-professional’ instruments and automating estimates of dendrometric parameters.

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ACCURACY ASSESSMENT OF UNDERWATER PHOTOGRAMMETRIC THREE DIMENSIONAL MODELLING FOR CORAL REEFS

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

10.5194/isprs-archives-xli-b5-821-2016 ◽

2016 ◽

Vol XLI-B5 ◽

pp. 821-828 ◽

Cited By ~ 1

Author(s):

T. Guo ◽

A. Capra ◽

M. Troyer ◽

A. Gruen ◽

A. J. Brooks ◽

...

Keyword(s):

Coral Cover ◽

Accuracy Assessment ◽

Low Cost ◽

Three Dimensional ◽

Point Clouds ◽

3D Modelling ◽

Relative Accuracy ◽

3D Point Clouds ◽

The Individual ◽

Working Distance

Recent advances in automation of photogrammetric 3D modelling software packages have stimulated interest in reconstructing highly accurate 3D object geometry in unconventional environments such as underwater utilizing simple and low-cost camera systems. The accuracy of underwater 3D modelling is affected by more parameters than in single media cases. This study is part of a larger project on 3D measurements of temporal change of coral cover in tropical waters. It compares the accuracies of 3D point clouds generated by using images acquired from a system camera mounted in an underwater housing and the popular GoPro cameras respectively. A precisely measured calibration frame was placed in the target scene in order to provide accurate control information and also quantify the errors of the modelling procedure. In addition, several objects (cinder blocks) with various shapes were arranged in the air and underwater and 3D point clouds were generated by automated image matching. These were further used to examine the relative accuracy of the point cloud generation by comparing the point clouds of the individual objects with the objects measured by the system camera in air (the best possible values). Given a working distance of about 1.5 m, the GoPro camera can achieve a relative accuracy of 1.3 mm in air and 2.0 mm in water. The system camera achieved an accuracy of 1.8 mm in water, which meets our requirements for coral measurement in this system.

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INDOOR NAVIGATION FROM POINT CLOUDS: 3D MODELLING AND OBSTACLE DETECTION

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

10.5194/isprsarchives-xli-b4-275-2016 ◽

2016 ◽

Vol XLI-B4 ◽

pp. 275-281 ◽

Cited By ~ 8

Author(s):

L. Díaz-Vilariño ◽

P. Boguslawski ◽

K. Khoshelham ◽

H. Lorenzo ◽

L. Mahdjoubi

Keyword(s):

Laser Scanner ◽

Route Planning ◽

Point Clouds ◽

3D Modelling ◽

Obstacle Detection ◽

Indoor Navigation ◽

3D Point Clouds ◽

Emergency Assistance ◽

Planning Methodology ◽

Real State

In the recent years, indoor modelling and navigation has become a research of interest because many stakeholders require navigation assistance in various application scenarios. The navigational assistance for blind or wheelchair people, building crisis management such as fire protection, augmented reality for gaming, tourism or training emergency assistance units are just some of the direct applications of indoor modelling and navigation. Navigational information is traditionally extracted from 2D drawings or layouts. Real state of indoors, including opening position and geometry for both windows and doors, and the presence of obstacles is commonly ignored. In this work, a real indoor-path planning methodology based on 3D point clouds is developed. The value and originality of the approach consist on considering point clouds not only for reconstructing semantically-rich 3D indoor models, but also for detecting potential obstacles in the route planning and using these for readapting the routes according to the real state of the indoor depictured by the laser scanner.

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INDOOR NAVIGATION FROM POINT CLOUDS: 3D MODELLING AND OBSTACLE DETECTION

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

10.5194/isprs-archives-xli-b4-275-2016 ◽

2016 ◽

Vol XLI-B4 ◽

pp. 275-281 ◽

Cited By ~ 1

Author(s):

L. Díaz-Vilariño ◽

P. Boguslawski ◽

K. Khoshelham ◽

H. Lorenzo ◽

L. Mahdjoubi

Keyword(s):

Laser Scanner ◽

Route Planning ◽

Point Clouds ◽

3D Modelling ◽

Obstacle Detection ◽

Indoor Navigation ◽

3D Point Clouds ◽

Emergency Assistance ◽

Planning Methodology ◽

Real State

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DEVELOPMENT OF A LASER SCANNER FOR POLYMER GEL DOSIMETRY

Anales AFA ◽

10.31527/analesafa.2020.31.2.55 ◽

2020 ◽

Vol 31 (2) ◽

pp. 55-61

Author(s):

D. Chacón ◽

M. Romero ◽

F. Mattea ◽

M. Valente

Keyword(s):

Low Cost ◽

Laser Scanner ◽

Absorbed Dose ◽

Medical Application ◽

Optical Methods ◽

Gel Dosimetry ◽

Polymer Gel ◽

Tissue Equivalent ◽

Polymer Gel Dosimetry ◽

Equivalent Properties

Advances of the medical application of ionizing radiation, and specifically in cancer treatment, are continuously evolving and gaining higher degrees of complexity. Therefore, the ability to determine and ensure the safety and precision of these techniques must be accompanied by novel dosimetry systems. Polymer gel dosimetry is one of the new and re-markable dosimetry systems that can quantitatively record the absorbed dose and register 3D dose distributions with high resolution while maintaining tissue-equivalent properties. Typical methods used to read the recorded signal in a polymer gel dosimeter, such as magnetic resonance imaging, X-ray tomography, and ultrasound-based techniques in-clude complex and expensive instruments. On the other hand, there are low-cost alternatives like optical methods that can be optimized and designed for the study of polymer gel dosimetry. The objective of this study is to present the de-sign, construction, development, and characterization of a low-cost laser scanner for bi-dimensional PGD analysis. With this equipment, characterization and optimization assays were performed on typical samples, and compared to those obtained by commercial or validated instruments with similar results, proving the capacity of the designed instrument as a reading tool for polymeric gel dosimetry.

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ASSESSING THE ACCURACY AND PRECISION OF IMPERFECT POINT CLOUDS FOR 3D INDOOR MAPPING AND MODELING

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-4-w6-3-2018 ◽

2018 ◽

Vol IV-4/W6 ◽

pp. 3-10

Author(s):

J. Chen ◽

O. E. Mora ◽

K. C. Clarke

Keyword(s):

Low Cost ◽

Random Noise ◽

Three Dimensional ◽

Laser Scanner ◽

Point Clouds ◽

Accuracy And Precision ◽

Wide Range ◽

Sharp Edges ◽

The Cost ◽

Indoor Spaces

Abstract. In recent years, growing public interest in three-dimensional technology has led to the emergence of affordable platforms that can capture 3D scenes for use in a wide range of consumer applications. These platforms are often widely available, inexpensive, and can potentially find dual use in taking measurements of indoor spaces for creating indoor maps. Their affordability, however, usually comes at the cost of reduced accuracy and precision, which becomes more apparent when these instruments are pushed to their limits to scan an entire room. The point cloud measurements they produce often exhibit systematic drift and random noise that can make performing comparisons with accurate data difficult, akin to trying to compare a fuzzy trapezoid to a perfect square with sharp edges. This paper outlines a process for assessing the accuracy and precision of these imperfect point clouds in the context of indoor mapping by integrating techniques such as the extended Gaussian image, iterative closest point registration, and histogram thresholding. A case study is provided at the end to demonstrate use of this process for evaluating the performance of the Scanse Sweep 3D, an ultra-low cost panoramic laser scanner.

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COMBINATION OF TLS POINT CLOUDS AND 3D DATA FROM KINECT V2 SENSOR TO COMPLETE INDOOR MODELS

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

10.5194/isprsarchives-xli-b5-659-2016 ◽

2016 ◽

Vol XLI-B5 ◽

pp. 659-666 ◽

Cited By ~ 2

Author(s):

E. Lachat ◽

T. Landes ◽

P. Grussenmeyer

Keyword(s):

Point Cloud ◽

Low Cost ◽

Measurement Techniques ◽

Laser Scanner ◽

Point Clouds ◽

Final Model ◽

Kinect V2 ◽

Multiple Sensors ◽

3D Data ◽

Final Data

The combination of data coming from multiple sensors is more and more applied for remote sensing issues (multi-sensor imagery) but also in cultural heritage or robotics, since it often results in increased robustness and accuracy of the final data. In this paper, the reconstruction of building elements such as window frames or door jambs scanned thanks to a low cost 3D sensor (Kinect v2) is presented. Their combination within a global point cloud of an indoor scene acquired with a terrestrial laser scanner (TLS) is considered. If the added elements acquired with the Kinect sensor enable to reach a better level of detail of the final model, an adapted acquisition protocol may also provide several benefits as for example time gain. The paper aims at analyzing whether the two measurement techniques can be complementary in this context. The limitations encountered during the acquisition and reconstruction steps are also investigated.

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Assessing Low-Cost Terrestrial Laser Scanners for Deriving Forest Structure Parameters

10.20944/preprints202107.0690.v1 ◽

2021 ◽

Author(s):

Atticus E. L. Stovall ◽

Jeff W Atkins

Keyword(s):

Structural Parameters ◽

Low Cost ◽

Laser Scanner ◽

Point Clouds ◽

Model Reconstruction ◽

Tree Model ◽

Factors Affecting ◽

Laser Scanners ◽

Tree Models ◽

Profile Reconstruction

The increasingly affordable price point of terrestrial laser scanners has led to a democratization of instrument availability, but the most common low-cost instruments have yet to be compared in terms of the consistency to measure forest structural attributes. Here, we compared two low-cost terrestrial laser scanners (TLS): the Leica BLK360 and the Faro Focus 120 3D. We evaluate the instruments in terms of point cloud quality, forest inventory estimates, tree-model reconstruction, and foliage profile reconstruction. Our direct comparison of the point clouds showed reduced noise in filtered Leica data. Tree diameter and height were consistent across instruments (4.4% and 1.4% error, respectively). Volumetric tree models were less consistent across instruments, with ~29% bias, depending on model reconstruction quality. In the process of comparing foliage profiles, we conducted a sensitivity analysis of factors affecting foliage profile estimates, showing a minimal effect from instrument maximum range (for forests less than ~50 m in height) and surprisingly little impact from degraded scan resolution. Filtered unstructured TLS point clouds must be artificially re-gridded to provide accurate foliage profiles. The factors evaluated in this comparison point towards necessary considerations for future low-cost laser scanner development and application in detecting forest structural parameters.

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