Design of the Fall-Block Sensing of the Railway Line Pantograph Based on 3D Machine Vision Sensors

As an important part of the electric locomotive in railway transportation, the sensing and inspection of the pantograph has a significant effect on the safe operation of the train. In general, the pantograph carbon slip detection items include slide wear detection, slip strip crack detection, carbon slip fall-block detection and slip strip wear detection. The emergence and development of structured light measurement technology with 3D sensors provide new technical means for the acquisition of spatial 3D information. The three-dimensional data can not only obtain more information but also reduce the data deviation, thereby improving the measurement accuracy and work efficiency. At present, few studies have been conducted on the slide block and partial wear of the carbon slide. Therefore, this paper studies the detection of the pantograph slide block based on 3D sensor measurement technology. The experimental results indicate that it is feasible to adopt 3D measurement technology to detect the fall-block of the pantograph slide. In addition, a sound detection effect can also be obtained.

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Evaluating Feature Extraction Methods with Synthetic Noise Patterns for Image-Based Modelling of Texture-Less Objects

Remote Sensing ◽

10.3390/rs12233886 ◽

2020 ◽

Vol 12 (23) ◽

pp. 3886

Author(s):

Jahanzeb Hafeez ◽

Jaehyun Lee ◽

Soonchul Kwon ◽

Sungjae Ha ◽

Gitaek Hur ◽

...

Keyword(s):

Feature Extraction ◽

3D Reconstruction ◽

Feature Matching ◽

Low Cost ◽

Three Dimensional ◽

Extraction Methods ◽

Planar Surfaces ◽

Vision Sensors ◽

3D Printed ◽

3D Information

Image-based three-dimensional (3D) reconstruction is a process of extracting 3D information from an object or entire scene while using low-cost vision sensors. A structure-from-motion coupled with multi-view stereo (SFM-MVS) pipeline is a widely used technique that allows 3D reconstruction from a collection of unordered images. The SFM-MVS pipeline typically comprises different processing steps, including feature extraction and feature matching, which provide the basis for automatic 3D reconstruction. However, surfaces with poor visual texture (repetitive, monotone, etc.) challenge the feature extraction and matching stage and affect the quality of reconstruction. The projection of image patterns while using a video projector during the image acquisition process is a well-known technique that has been shown to be successful for such surfaces. In this study, we evaluate the performance of different feature extraction methods on texture-less surfaces with the application of synthetically generated noise patterns (images). Seven state-of-the-art feature extraction methods (HARRIS, Shi-Tomasi, MSER, SIFT, SURF, KAZE, and BRISK) are evaluated on problematic surfaces in two experimental phases. In the first phase, the 3D reconstruction of real and virtual planar surfaces evaluates image patterns while using all feature extraction methods, where the patterns with uniform histograms have the most suitable morphological features. The best performing pattern from Phase One is used in Phase Two experiments in order to recreate a polygonal model of a 3D printed object using all of the feature extraction methods. The KAZE algorithm achieved the lowest standard deviation and mean distance values of 0.0635 mm and −0.00921 mm, respectively.

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Three-Dimensional Ultrasonic Crack Detection in Anisotropic Materials

Research in Nondestructive Evaluation ◽

10.1080/09349849708968121 ◽

1997 ◽

Vol 9 (2) ◽

pp. 59-79 ◽

Cited By ~ 14

Author(s):

J. Mattsson ◽

A. J. Niklasson ◽

A. Eriksson

Keyword(s):

Crack Detection ◽

Three Dimensional ◽

Anisotropic Materials

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Analyzing the Impact of X-Ray Tomography on the Reliability of Integrated Circuits

ISTFA 2015: Conference Proceedings from the 41st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2015p0154 ◽

2015 ◽

Author(s):

Halit Dogan ◽

Md Mahbub Alam ◽

Navid Asadizanjani ◽

Sina Shahbazmohamadi ◽

Domenic Forte ◽

...

Keyword(s):

Integrated Circuits ◽

Integrated Circuit ◽

3D Imaging ◽

Three Dimensional ◽

Serial Sectioning ◽

Promising Technique ◽

Flash Memories ◽

X Ray ◽

3D Information ◽

The Impact

Abstract X-ray tomography is a promising technique that can provide micron level, internal structure, and three dimensional (3D) information of an integrated circuit (IC) component without the need for serial sectioning or decapsulation. This is especially useful for counterfeit IC detection as demonstrated by recent work. Although the components remain physically intact during tomography, the effect of radiation on the electrical functionality is not yet fully investigated. In this paper we analyze the impact of X-ray tomography on the reliability of ICs with different fabrication technologies. We perform a 3D imaging using an advanced X-ray machine on Intel flash memories, Macronix flash memories, Xilinx Spartan 3 and Spartan 6 FPGAs. Electrical functionalities are then tested in a systematic procedure after each round of tomography to estimate the impact of X-ray on Flash erase time, read margin, and program operation, and the frequencies of ring oscillators in the FPGAs. A major finding is that erase times for flash memories of older technology are significantly degraded when exposed to tomography, eventually resulting in failure. However, the flash and Xilinx FPGAs of newer technologies seem less sensitive to tomography, as only minor degradations are observed. Further, we did not identify permanent failures for any chips in the time needed to perform tomography for counterfeit detection (approximately 2 hours).

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Elastic transformation of histological slices allows precise co-registration with microCT data sets for a refined virtual histology approach

Scientific Reports ◽

10.1038/s41598-021-89841-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jonas Albers ◽

Angelika Svetlove ◽

Justus Alves ◽

Alexander Kraupner ◽

Francesca di Lillo ◽

...

Keyword(s):

Three Dimensional ◽

High Specificity ◽

Histopathological Analysis ◽

Specific Information ◽

Data Sets ◽

Virtual Histology ◽

Novel Approach ◽

Cell Tissue ◽

Immuno Histochemistry ◽

3D Information

AbstractAlthough X-ray based 3D virtual histology is an emerging tool for the analysis of biological tissue, it falls short in terms of specificity when compared to conventional histology. Thus, the aim was to establish a novel approach that combines 3D information provided by microCT with high specificity that only (immuno-)histochemistry can offer. For this purpose, we developed a software frontend, which utilises an elastic transformation technique to accurately co-register various histological and immunohistochemical stainings with free propagation phase contrast synchrotron radiation microCT. We demonstrate that the precision of the overlay of both imaging modalities is significantly improved by performing our elastic registration workflow, as evidenced by calculation of the displacement index. To illustrate the need for an elastic co-registration approach we examined specimens from a mouse model of breast cancer with injected metal-based nanoparticles. Using the elastic transformation pipeline, we were able to co-localise the nanoparticles to specifically stained cells or tissue structures into their three-dimensional anatomical context. Additionally, we performed a semi-automated tissue structure and cell classification. This workflow provides new insights on histopathological analysis by combining CT specific three-dimensional information with cell/tissue specific information provided by classical histology.

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3D monitoring of the surface slippage effect on micro-particle sedimentation by digital holographic microscopy

Scientific Reports ◽

10.1038/s41598-021-92498-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Majid Panahi ◽

Ramin Jamali ◽

Vahideh Farzam Rad ◽

Mojtaba Khorasani ◽

Ahamd Darudi ◽

...

Keyword(s):

Slip Length ◽

Particle Interaction ◽

Three Dimensional ◽

Digital Holographic Microscopy ◽

Particle Sedimentation ◽

Micro Particles ◽

Slippage Effect ◽

Holographic Microscopy ◽

3D Information ◽

Experimental Findings

AbstractIn several phenomena in biology and industry, it is required to understand the comprehensive behavior of sedimenting micro-particles in fluids. Here, we use the numerical refocusing feature of digital holographic microscopy (DHM) to investigate the slippage effect on micro-particle sedimentation near a flat wall. DHM provides quantitative phase contrast and three-dimensional (3D) imaging in arbitrary time scales, which suggests it as an elegant approach to investigate various phenomena, including dynamic behavior of colloids. 3D information is obtained by post-processing of the recorded digital holograms. Through analysis of 3D trajectories and velocities of multiple sedimenting micro-particles, we show that proximity to flat walls of higher slip lengths causes faster sedimentation. The effect depends on the ratio of the particle size to (1) the slip length and (2) its distance to the wall. We corroborate our experimental findings by a theoretical model which considers both the proximity and the particle interaction to a wall of different hydrophobicity in the hydrodynamic forces.

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Virtual Archaeology of Death and Burial: A Procedure for Integrating 3D Visualization and Analysis in Archaeothanatology

Open Archaeology ◽

10.1515/opar-2020-0152 ◽

2021 ◽

Vol 7 (1) ◽

pp. 540-555

Author(s):

Hayley L. Mickleburgh ◽

Liv Nilsson Stutz ◽

Harry Fokkens

Keyword(s):

Spatial Information ◽

3D Visualization ◽

Rapid Development ◽

Three Dimensional ◽

3D Models ◽

The Body ◽

Test Case ◽

Archaeology Of Death ◽

Human Burials ◽

3D Information

Abstract The reconstruction of past mortuary rituals and practices increasingly incorporates analysis of the taphonomic history of the grave and buried body, using the framework provided by archaeothanatology. Archaeothanatological analysis relies on interpretation of the three-dimensional (3D) relationship of bones within the grave and traditionally depends on elaborate written descriptions and two-dimensional (2D) images of the remains during excavation to capture this spatial information. With the rapid development of inexpensive 3D tools, digital replicas (3D models) are now commonly available to preserve 3D information on human burials during excavation. A procedure developed using a test case to enhance archaeothanatological analysis and improve post-excavation analysis of human burials is described. Beyond preservation of static spatial information, 3D visualization techniques can be used in archaeothanatology to reconstruct the spatial displacement of bones over time, from deposition of the body to excavation of the skeletonized remains. The purpose of the procedure is to produce 3D simulations to visualize and test archaeothanatological hypotheses, thereby augmenting traditional archaeothanatological analysis. We illustrate our approach with the reconstruction of mortuary practices and burial taphonomy of a Bell Beaker burial from the site of Oostwoud-Tuithoorn, West-Frisia, the Netherlands. This case study was selected as the test case because of its relatively complete context information. The test case shows the potential for application of the procedure to older 2D field documentation, even when the amount and detail of documentation is less than ideal.

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3D Profile Variety Measurement of Pectoral Fin in Fish Fast Start

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.83.280 ◽

2011 ◽

Vol 83 ◽

pp. 280-284

Author(s):

Ming Jiang ◽

Shu Zhang ◽

Xiao Yuan He

Keyword(s):

Fourier Transform ◽

High Speed ◽

Kinetic Characteristic ◽

Three Dimensional ◽

Pectoral Fin ◽

Fourier Transform Profilometry ◽

Fast Start ◽

Fringe Patterns ◽

3D Information ◽

3D Profile

Fast-starts are brief, sudden accelerations used by fish during predator-prey encounters. In this paper, a three-dimensional (3D) test and analysis method is critical to understand the function of the pectoral fin during maneuvers. An experiment method based on Fourier Transform Profilometry for 3D pectoral fin profile variety during fish maneuvers is proposed. This method was used in a carp fast-start during prey. Projecting the moiré fringes onto a carp pectoral fin it will produce the deformed fringe patterns contain 3D information. A high speed camera captures these time-sequence images. By Fourier transform, filter, inverse Fourier transform and unwrap these phase maps in 3D phase space, the complex pectoral fin profile variety were really reconstructed. The present study provides a new method to quantify the analysis of kinetic characteristic of the pectoral fin during maneuvers.

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Research on Three-Dimensional Displacement Measurement Technology of the Beating Heart

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.403-408.5182 ◽

2011 ◽

Vol 403-408 ◽

pp. 5182-5186

Author(s):

Sheng Yi Yang ◽

An Gu ◽

Meng Li ◽

Chang Jian Lu

Keyword(s):

Heart Surgery ◽

Classical Mechanics ◽

Three Dimensional ◽

Beating Heart ◽

Displacement Measurement ◽

Surgical Instruments ◽

Analytical Models ◽

Measurement Technology ◽

Position Measurement ◽

Mechanics Of Materials

In robotic-assisted heart surgery, the method of canceling the relative motion between the surgical site on the heart and the surgical instruments was introduced in this paper. A whisker sensor was designed for three dimensional position measurement in beating heart surgery. Analytical models were developed according to the classical mechanics of materials, and theoretical formulas were derived for displacement measurement. Feasibility and effectiveness of the method were verified by simulation experiments. We can obtain measurements by loading displacement to the whisker sensor, and draw conclusions by comparing the measurements.

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Comparison of Depth Camera and Terrestrial Laser Scanner in Monitoring Structural Deflections

Sensors ◽

10.3390/s21010201 ◽

2020 ◽

Vol 21 (1) ◽

pp. 201

Author(s):

Michael Bekele Maru ◽

Donghwan Lee ◽

Kassahun Demissie Tola ◽

Seunghee Park

Keyword(s):

Optical Sensors ◽

Point Cloud ◽

Three Dimensional ◽

Laser Scanner ◽

Point Clouds ◽

Depth Camera ◽

Terrestrial Laser Scanner ◽

Cloud Data ◽

3D Point Clouds ◽

3D Information

Modeling a structure in the virtual world using three-dimensional (3D) information enhances our understanding, while also aiding in the visualization, of how a structure reacts to any disturbance. Generally, 3D point clouds are used for determining structural behavioral changes. Light detection and ranging (LiDAR) is one of the crucial ways by which a 3D point cloud dataset can be generated. Additionally, 3D cameras are commonly used to develop a point cloud containing many points on the external surface of an object around it. The main objective of this study was to compare the performance of optical sensors, namely a depth camera (DC) and terrestrial laser scanner (TLS) in estimating structural deflection. We also utilized bilateral filtering techniques, which are commonly used in image processing, on the point cloud data for enhancing their accuracy and increasing the application prospects of these sensors in structure health monitoring. The results from these sensors were validated by comparing them with the outputs from a linear variable differential transformer sensor, which was mounted on the beam during an indoor experiment. The results showed that the datasets obtained from both the sensors were acceptable for nominal deflections of 3 mm and above because the error range was less than ±10%. However, the result obtained from the TLS were better than those obtained from the DC.

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Retrieval of 3D information in X-ray dark-field imaging with a large field of view

Scientific Reports ◽

10.1038/s41598-021-02960-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jana Andrejewski ◽

Fabio De Marco ◽

Konstantin Willer ◽

Wolfgang Noichl ◽

Theresa Urban ◽

...

Keyword(s):

Three Dimensional ◽

Dark Field ◽

Large Field ◽

X Ray ◽

Dark Field Imaging ◽

Beam Geometry ◽

Different Dimensions ◽

3D Information ◽

Human Thorax ◽

Field Imaging

AbstractX-ray dark-field imaging is a widely researched imaging technique, with many studies on samples of very different dimensions and at very different resolutions. However, retrieval of three-dimensional (3D) information for human thorax sized objects has not yet been demonstrated. We present a method, similar to classic tomography and tomosynthesis, to obtain 3D information in X-ray dark-field imaging. Here, the sample is moved through the divergent beam of a Talbot–Lau interferometer. Projections of features at different distances from the source seemingly move with different velocities over the detector, due to the cone beam geometry. The reconstruction of different focal planes exploits this effect. We imaged a chest phantom and were able to locate different features in the sample (e.g. the ribs, and two sample vials filled with water and air and placed in the phantom) to corresponding focal planes. Furthermore, we found that image quality and detectability of features is sufficient for image reconstruction with a dose of 68 μSv at an effective pixel size of $$0.357 \times {0.357}\,\mathrm{mm}^{2}$$ 0.357 × 0.357 mm 2 . Therefore, we successfully demonstrated that the presented method is able to retrieve 3D information in X-ray dark-field imaging.

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