Ultrasonic 3D Research Articles

Reliability of measuring half-cycle cervical range of motion may be increased using a spirit level for calibration

BackgroundAssessments of range of motion (ROM) represent an essential part of clinical diagnostics. Ultrasonic movement analyses have been demonstrated to provide reliable results when analyzing complete amplitudes (e.g., flexion-extension). However, due to subjective determination of the starting position, the assessment of half-cycle movements (e.g, flexion only) is less reproducible. ObjectivesThe present study aimed to examine the reliability of measuring half-cycle cervical ROM using a spirit level for calibration. Method20 healthy subjects (30 ± 12yrs, 7♂, 13♀) participated in the randomized, controlled, cross-over trial. In two testing sessions with one week of wash-out in between, cervical ROM was measured by means of an ultrasonic 3D movement analysis system using a test-retest design (baseline and 5 min post baseline). The sessions differed with reference to the mask carrying the ultrasound markers. It was removed during the 5 min break (mask off) or not (mask on). To determine the resting position, a bull's eye spirit level was used in each measurement. ResultsWith ICC values of 0.90–0.98 (mask on, p < 0.001) and 0.90 to 0.97 (mask off, p < 0.001), both examined conditions demonstrated excellent test-retest reliability for separating the cycles regarding all movement planes. ConclusionCervical ROM during half-cycle movements can be assessed with excellent reliability using a spirit level. In contrast to subjective determination of the starting position, analyzing complete movement planes does not increase reliability. Using a defined and objective zero positioning allows the evaluation of repositioning tasks.

3D Ultrasonic Anemometer with tetrahedral arrangement of sensors

The paper describes the structure, operating principle and software of the ultrasonic velocity and air flow meter with the arrangement of sensors at the vertices of the tetrahedron. This design, with a minimum of sensors, makes it possible to measure the velocity components in three directions at once. The influence of dimensions of the construction on the metrological characteristics of the device is evaluated.

Metal scaffolds for acoustic trapping of polystyrene particles in water suspensions

The concept of ultrasonic 3D caging is based in wells designed to host three orthogonal half-wave acoustic resonances defined by its three dimensions generating a single-pressure-node in the center where particles collect to aggregate. A replacement of the planar shapes in these cavities by curved walls introduce changes in the pressure patterns, generating different effects on the particles exposed to the acoustic field. Here we present an experimental study of the acoustic behavior of aqueous suspensions of micron-sized polystyrene particles (Cv~1%) exposed to ultrasounds at a frequency f~1MHz in a metal scaffold made up of stainless steel wires crossed-linked orthogonally to form a mesh with a light of 1mm (something larger than λ/2). Once applied the acoustic field, the particles are rapidly attracted by the rods of the mesh distances much larger than their diameter (Φp = 6µm), where are trapped and remain adhered to the scaffold during the acoustic actuation and even later, providing stable aggregate...

MULTI-SOURCE 3D MODELS SUPPORTING ULTRASONIC TEST TO INVESTIGATE AN EGYPTIAN SCULPTURE OF THE ARCHAEOLOGICAL MUSEUM IN BOLOGNA

Abstract. The paper presents the workflow and the results of an ultrasonic 3D investigation and a 3D survey application aimed at the assessment of the internal integrity of an ancient sculpture. The work aimed at highlighting the ability of methods devoted to the 3D geometry acquisition of small objects when applied to diagnosis performed by geophysical investigation. In particular, two methods widely applied for small objects modelling are considered and compared, the digital Photogrammetry with the Structure from Motion (SFM) technique and hand-held 3D scanners. The study concludes with the aim to enhance the final graphical representation of the tomographic results and to subject the obtained results to a quantitative analysis. The survey is applied to the Egyptian naophorous statue of Amenmes and Reshpu, which dates to the reign of Ramses II (1279-1213 BC) or later and is now preserved in the Civic Archaeological Museum in Bologna. In order to evaluate the internal persistency of fractures and visible damages, a 3D Ultrasonic Tomographic Imaging (UTI) test has been performed and a multi-sensor survey (image and range based) was conducted, in order to evaluate the locations of the source and receiver points as accurate as possible The presented test allowed to evaluate the material characteristics, its porosity and degradation state, which particularly affect the lower part of the statue. More in general, the project demonstrated how solution coming from the field of 3D modelling of Cultural Heritage allow the application of 3D ultrasonic tomography also on objects with complex shapes, in addition to the improved representation of the obtained results.

Ultrasonic 3D Reconstruction and Measurement of Lacrimal Sac in Normal Adult Chinese Population

Ultrasonic 3D Reconstruction and Measurement of Lacrimal Sac in Normal Adult Chinese Population

Ultrasonic 3D Shape Milling for Acrylic Resin Optical Products

Acrylic resin is employed in optical products such as lenses and light guiding panels because it is highly transparent. Optical components made using acrylic resin require hand polishing by skilled workers to give a mirror finish to the surface of components in order to obtain the required optical properties. However, polishing takes a lot of time and two problems that exist are that skilled workers are aging and that young skilled workers are few in number. In this research, a method of ultrasonic milling of acrylic resin which would give a mirror-surface finish to acrylic resin products without the need for hand polishing by skilled workers was proposed.

Investigation of synthetic aperture methods in ultrasound surface imaging using elementary surface types

Synthetic aperture imaging methods have been employed widely in recent research in non-destructive testing (NDT), but uptake has been more limited in medical ultrasound imaging. Typically offering superior focussing power over more traditional phased array methods, these techniques have been employed in NDT applications to locate and characterise small defects within large samples, but have rarely been used to image surfaces. A desire to ultimately employ ultrasonic surface imaging for bone surface geometry measurement prior to surgical intervention motivates this research, and results are presented for initial laboratory trials of a surface reconstruction technique based on global thresholding of ultrasonic 3D point cloud data. In this study, representative geometry artefacts were imaged in the laboratory using two synthetic aperture techniques; the Total Focusing Method (TFM) and the Synthetic Aperture Focusing Technique (SAFT) employing full and narrow synthetic apertures, respectively.Three high precision metallic samples of known geometries (cuboid, sphere and cylinder) which featured a range of elementary surface primitives were imaged using a 5MHz, 128 element 1D phased array employing both SAFT and TFM approaches. The array was manipulated around the samples using a precision robotic positioning system, allowing for repeatable ultrasound derived 3D surface point clouds to be created. A global thresholding technique was then developed that allowed the extraction of the surface profiles, and these were compared with the known geometry samples to provide a quantitative measure of error of 3D surface reconstruction. The mean errors achieved with optimised SAFT imaging for the cuboidal, spherical and cylindrical samples were 1.3mm, 2.9mm and 2.0mm respectively, while those for TFM imaging were 3.7mm, 3.0mm and 3.1mm, respectively. These results were contrary to expectations given the higher information content associated with the TFM images. However, it was established that the reduced error associated with the SAFT technique was associated with significant reductions in side lobe levels of approximately 24dB in comparison to TFM imaging, although this came at the expense of reduced resolution and coverage.

Monitoring of autogenous crack healing in cementitious materials by the nonlinear modulation of ultrasonic coda waves, 3D microscopy and X-ray microtomography

In this work the non-destructive monitoring of the self-healing progress of cracked mortars is presented through the use of three combined methods: nonlinear Coda Wave Interferometry, 3D microscopy and X-ray computed microtomography (CT). The aim of the acoustic method is to compare, at various healing stages, both the ultrasonic velocity variations and decorrelation coefficients between a reference coda signal and a signal perturbed by a high level lower-frequency elastic wave. The decrease in the relative variation of the extracted nonlinearities demonstrates its ability to accurately monitor global crack filling. 3D microscopy also reveals this capability. Measurement results of these two techniques agree for the influence of age at cracking on healing potential. In reducing the voxel size to 12μm, X-ray CT images confirm the creation of localized bridges between crack faces and provide information on their location.

Low-frequency three-dimensional ultrasonic tomography

The possibility of making ultrasonic 3D tomographs for medical diagnostics of soft tissues was established. The choice of frequencies of ultrasonic pulses of 300–500 kHz was due to low absorption in soft tissues within this range. The reverse problems of ultrasonic tomography, which are three-dimensional and nonlinear, have been considered in a model that takes into account both wave effects and absorption. The effectiveness of algorithms to solve the reverse problems that were developed has been illustrated by model calculations. The velocity configuration has been shown to be recovered better than the function that describes absorption in soft tissues.

Hardware and software architectures for computationally efficient three‐dimensional ultrasonic data compression

Ultrasonic industrial and medical imaging applications involve acquisition of large amount of volumetric data in real time. Therefore, data storage becomes critical in many current day applications which utilise ultrasound technology. Compressing the acquired data allows possessing minimal storage and also helps to rapidly transmit information to remote locations for expert analysis. The objective of this study is to design computationally efficient architectures for implementing discrete wavelet transform-based ultrasonic three-dimensional (3D) data compression algorithm on a reconfigurable ultrasonic system-on-chip (SoC) hardware platform. In this study, hardware and software architectures of the 3D ultrasonic compression algorithm are realised using Xilinx Zynq all programmable SoC. This study demonstrates that, compressing 33 MB of experimental ultrasonic 3D data into 0.42 MB (98.7% compression) requires only 84 ms for hardware architecture, and 1 min for software architecture, making both designs highly suitable for real-time ultrasonic imaging applications. Furthermore, the 3D compression is implemented by using Open Computing Language (OpenCL) targeted on Nvidia GT 750M graphical processing unit. OpenCL implementation of ultrasonic 3D compression algorithm completes the execution in <1 sec. This approach provides improved computational performance as that of hardware architecture, and comparable flexibility as that of software implementation.

3D Isosceles Triangular Ultrasonic Path of Transit-Time Ultrasonic Flowmeter: Theoretical Design and CFD Simulations

Increasing the coverage rate of ultrasonic path to flow field is helpful to improve measurement results' accuracy of transit-time ultrasonic flowmeters while asymmetric flow or turbulence exists. In this paper, a 3D isosceles triangular ultrasonic path is presented considering the width of the ultrasonic signal and the maximum coverage rate of the ultrasonic path to flow field. To evaluate the feasibility and effectiveness of the path proposed, computational fluid dynamics simulations of three pipeline configurations, including straight pipeline, single elbow, and contracted pipeline upstream ultrasonic flowmeter 3D <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pipe</sub> (diameter of pipeline, D <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pipe</sub> ), 5D <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pipe</sub> , or 8D <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pipe</sub> long are performed. In particular, inlet velocity of flow ranges from 0.1 to 10 m/s. Meanwhile, control simulation of U-type ultrasonic path is discussed to verify the effect of coverage rate of ultrasonic path to flow field on measurement results. It is shown that the proposed 3D isosceles triangular ultrasonic path, whose coverage rate is 54%, does well in improving the stability and accuracy of measurement results while pipeline configuration upstream flowmeter changes.

The Factor Analysis of Meso-Oligotrophic Peatland Medla-Pev-Njur Data

Measurements are taken by the staff of Institute of biology since May, 2012 on the meso-oligotrophic peatland located in a taiga in the European Northeast of Russia in 40km from Syktyvkar. Measurements of all parameters were carried out by method of microvortex pulsations with use of a gas analyzer of Li-7500A and the ultrasonic CSAT 3D anemometer at height 3,93m. Frequency of measurements is-10Hz. Measurements included also meteorological characteristics.In this work, mutual influence of the measured characteristics is studied. The analysis included 54 parameters, such as concentration of methane, carbon dioxide, water vapor, the air temperature, wind speed components, atmospheric pressure, average values of fluctuations of squares a component of speed of a wind, work of fluctuations horizontal a speed component with vertical, vertical streams of heat, methane, carbon dioxide and water vapor, kinetic energy of turbulence, dynamic speed, estimates of local derivatives on time of average values of temperature, a component of speed, atmospheric pressure, methane, carbon oxide and water vapor, and also average on 30minut intervals of time of values of atmospheric pressure, density of air, relative humidity, streams of carbon dioxide and methane without adjustments, albedo, all types of radiation, soil temperature at two depths and photosynthetic radiation.

Ultrasonic Phased Array 3D Imaging for the Steel Butt Weld Defects

Ultrasonic phased array imaging detection technology combinating the focused beam and array probe movement can get powerful test information. It has been widely used in the steel butt weld detection. For making up the limitations of 2D view, in this paper,we used one-dimensional linear array probe, got 2D slice view data obtained by phased array ultrasonic S-scan, through software programming algorithm to realize 3D reconstruction of steel butt weld typical defects. Experiment shows that it can display more intuitive performance of the defects in space. Revealing a better shape, size and orientation information. Providing a reference for the final evaluation of the defect.

3D Ultrasonic Rangefinder on a Chip

An ultrasonic 3D rangefinder uses an array of AlN MEMS transducers and custom readout electronics to localize targets over a $\pm 45^{\circ}$ field of view up to 1 m away. The rms position error at 0.5 m range is 0.4 mm, 0.2 $^{\circ}$ , and 0.8 $^{\circ}$ for the range, x-angle, and y-angle axes, respectively. The 0.18 $\mu{\rm m}$ CMOS ASIC comprises 10 independent channels with separate high voltage transmitters, readout amplifiers, and switched-capacitor bandpass $\Sigma\Delta$ ADCs with built-in continuous time anti-alias filtering. For a 1 m maximum range, power dissipation is 400 $\mu{\rm W}$ at 30 fps. For a 0.3 m maximum range, the power dissipation scales to 5 $\mu{\rm W/ch}$ at 10 fps.

Proposal to Construct a 3D Image Viewer Based on a Commercial Ultrasonic 2D Imaging System

This paper describes an approach to develop a procedure to reconstruct 3D volumes of breast cancer by using 2D ultrasonic (US) images in order to provide the shape and the dimensions of the cancer. We obtained 91.66% accuracy in the 3D reconstruction process. Breast and breast cancer phantoms were made in order to mimic acoustic properties (speed propagation). The US images of the phantoms were taken with commercial US equipment (Prosound 6, Aloka) by using a convex transducer probe (3-6MHz and 82° scanning angle), which was moved with a mechanical positioner with a resolution of 0.1mm.

Technology Update: New 3D Ultrasonic System Tests Pipeline Integrity

Technology Update The global oil and gas industry’s vast infrastructure includes many pipelines that were manufactured decades ago, and the intensive quality control processes in place have generally ensured that they have stood the test of time. As the technologies adopted by the industry to optimize drilling campaigns have evolved, the equipment used in the pipeline testing process has improved as well. Nondestructive testing (NDT) is used across the industry to inspect pipelines for defects that are impossible to discover with the human eye. NDT covers a wide range of methods, such as radiography and ultrasonic testing, by which pipelines can be inspected without altering their physical properties. This allows for highly productive testing, saving time and money as well as providing valuable evaluation, troubleshooting, and research. Ultrasonic Inspection Ultrasonic testing makes use of sound energy to examine specific components of a pipeline, such as girth welds, thus allowing for flaw detection and sizing. The testing process is principally used to examine welds in pipelines before they are accepted for use and is vital in ensuring that the pipelines can withstand the kinds of pressures they will be subjected to in an industrial setting. Any defects in the weld could have devastating consequences for safety and the environment. Ultrasonic inspection using the pulse echo (PE) technique or time of flight diffraction (ToFD) is widely used throughout the industry to assess weld integrity. However, quantitative defect characterization with PE remains challenging because the signal caused by the reflection at a point of defect is highly dependent on the defect’s orientation in relation to the ultrasonic beam. ToFD has sizing capabilities, when diffraction signals are present, but is limited in its ability to characterize flaws. In phased-array inspection, the image obtained from sectorial scans cannot be directly related to the defect’s size and orientation. Data display and interpretation are not straightforward and require operator skills and experience. Ultrasonic inspection would be better and more reliable if a method would allow direct imaging of defects. 3D Ultrasonic Imaging A recent significant advance in the field of NDT developed by Applus RTD is a 3D ultrasonic technology that uses inverse wave field extrapolation (IWEX) to enable detailed inspection and mapping of defects within critical pieces of pipework. The technology extrapolates wave field recordings back into space toward all points in the area under investigation. If at one of those points a scatterer (e.g., a defect) is present, the backward-extrapolated wave field has high amplitude, and the resulting image will show increased intensity at that location. If this is done for all points in the image, the location and shape of the scatterer can be determined.

Short-term effects of acupuncture and stretching on myofascial trigger point pain of the neck: A blinded, placebo-controlled RCT

This trial aimed to evaluate the short-term effectiveness of acupuncture plus stretching to reduce pain and improve range of motion in patients afflicted by cervical myofascial pain syndrome. Randomized, blinded, placebo-controlled crossover study. Nineteen patients (11 females, eight males, 33 ± 14 years) with myofascial neck pain in randomized order received the following treatments with one week washout between: acupuncture, acupuncture plus stretching, and placebo laser acupuncture. Mechanical pain threshold (MPT, measured with a pressure algometer) represented the primary outcome. Secondary outcomes were motion-related pain (Visual Analogue Scale, VAS) and cervical range of motion (ROM, recorded by means of an ultrasonic 3D movement analysis system). Outcomes were assessed immediately prior as well as 5, 15 and 30 min post treatment. Friedman tests with post hoc Bonferroni-Holm correction were applied to compare differences between treatments. Both acupuncture as well as acupuncture plus stretching increased MPT by five, respectively, 11 percent post treatment. However, only acupuncture in combination with stretching was superior to placebo (p<0.05). There were no significant differences between interventions at 15 and 30 min post treatment. VAS did not differ between treatments at any measurement. Five minutes after application of acupuncture plus stretching, ROM was significantly increased in the frontal and the transversal plane compared to placebo (p<0.05). The combination of acupuncture and stretching could represent a suitable treatment option to improve cervical movement behavior and reduce trigger point pain in the short-term. However, additional studies further discriminating the placebo effects are still warranted.

Analysis of fatigue properties and failure mechanisms of Ti6Al4V in the very high cycle fatigue regime using ultrasonic technology and 3D laser scanning vibrometry

Accelerated fatigue tests with Ti6Al4V were carried out using a 20kHz ultrasonic testing facility to investigate the cyclic deformation behavior in the Very High Cycle Fatigue (VHCF) regime in detail. Beside parameters like the ultrasonic generator power and the displacement of the specimen, a 3D laser scanning vibrometer was used to characterize the oscillation and fatigue behavior of the Ti-alloy. The course of the S–Nf curve at the stress ratio R=−1 shows a significant decrease of the bearable stress amplitude and a change from surface to subsurface failures in the VHCF regime for more than 107 cycles. Microscopic investigations of the distribution of the α- and β-phase of Ti6Al4V indicate that inhomogeneities in the phase distribution are reasons for the internal crack initiation. High resolution vibrometry was used to visualize the eigenmode of the designed VHCF-specimen at 20kHz in the initial state and to indicate local changes in the eigenmodes as a result of progressing fatigue damage. Non-contact strain measurements were realized and used to determine the stress amplitude. The determined stress amplitudes were correlated with strain gauge measurements and finite element analysis.

Non-invasive Techniques of Fetal Diagnosis and Therapy in Perinatal Medicine

Aims: Invasive techniques in fetal diagnosis and therapy are gradually changing to noninvasive methods, which would be presented in this article as well. Methods: Noninvasive methods in fetal diagnosis are reviewed. Results: External ultrasonic Doppler autocorrelation fetal monitor; ultrasonic Doppler fetal actocardiogram; ultrasonic 2D, 3D, 4D imaging methods, pulsed Doppler blood flow record, color and power Doppler flow mappings, gray level histogram width method in the prediction of neonatal RDS in preterm fetal lung; other tissue characterization techniques and recent noninvasive prenatal test (NIPT) in fetal diagnoses, high intensity focused ultrasound ablation for the TRAP sequence in monochorionic twins in fetal therapy were presented. Conclusion: Noninvasive methods were introduced to fetal studies to perform fetal diagnosis and therapy safely

ULTRASONIC IMAGE DIAGNOSTIC APPARATUS

An image processor includes a signal processing circuit for performing signal processing on three-dimensional echo signals transmitted from an ultrasonic 3D probe, a memory for storing at least one set of plural sets of three-dimensional echo data converted by the signal processing circuit, a large capacity storage unit, a control circuit for controlling input/output signals from an input unit, an image processing circuit for performing image processing such as coordinate conversion based on the three-dimensional echo data stored in the memory, a display circuit for displaying the ultrasonic three-dimensional image processed by the image processing circuit, and a CPU for performing calculation for “volume measurement”. Accordingly, a tissue of interest can be easily and accurately measured.