The use of Carbon Fibre Reinforced Plastic (CFRP) composite materials for critical components has significantly surged within the energy and aerospace industry. With this rapid increase in deployment, reliable post-manufacturing Non-Destructive Evaluation (NDE) is critical for verifying the mechanical integrity of manufactured components. To this end, an automated Ultrasonic Testing (UT) NDE process delivered by an industrial manipulator was developed, greatly increasing the measurement speed, repeatability, and locational precision, while increasing the throughput of data generated by the selected NDE modality.
View Article and Find Full Text PDFMn:PIN-PMN-PT piezocrystal is investigated to determine whether its enhanced energy density makes it a candidate transducer material for power ultrasonics applications. To this end, the electromechanical and vibrational characteristics of a simple configuration of a bolted Langevin transducer (BLT) and then an ultrasonic surgical device, both incorporating Mn:PIN-PMN-PT piezocrystal, are compared with the same transducer configurations incorporating a conventional hard PZT piezoceramic commonly used in high-power ultrasonic transducers. The material properties of Mn:PIN-PMN-PT are determined using a single sample characterisation technique and these are used in finite element analysis (FEA) to design and then fabricate the BLT and ultrasonic surgical device, tuned to the first and second longitudinal modes at 20 kHz respectively.
View Article and Find Full Text PDFPhase-change nanodroplets (PCND;NDs) are emulsions with a perfluorocarbon (PFC) core that undergo acoustic vaporisation as a response to ultrasound (US). Nanodroplets change to microbubbles and cavitate while under the effect of US. This cavitation can apply forces on cell connections in biological barrier membranes, such as the blood-brain barrier (BBB), and trigger a transient and reversible increased permeability to molecules and matter.
View Article and Find Full Text PDFDriven by the aim of realizing functional robotic systems at the milli- and submillimetre scale for biomedical applications, the area of magnetically driven soft devices has received significant recent attention. This has resulted in a new generation of magnetically controlled soft robots with patterns of embedded, programmable domains throughout their structures. This type of programmable magnetic profiling equips magnetic soft robots with shape programmable memory and can be achieved through the distribution of discrete domains (voxels) with variable magnetic densities and magnetization directions.
View Article and Find Full Text PDFJ Med Ultrason (2001)
October 2022
Purpose: Quantitative ultrasound (QUS) infers properties about tissue microstructure from backscattered radio-frequency ultrasound data. This paper describes how to implement the most practical QUS parameters using an ultrasound research system for tissue differentiation.
Methods: This study first validated chicken liver and gizzard muscle as suitable acoustic phantoms for human brain and brain tumour tissues via measurement of the speed of sound and acoustic attenuation.
Annu Int Conf IEEE Eng Med Biol Soc
November 2021
Sonomyography refers to the measurement of muscle activity with an ultrasonic transducer. It is a candidate modality for applications in diagnosis of muscle conditions, rehabilitation engineering and prosthesis control as an alternative to electromyography. We propose a mechanically-flexible piezoelectric sonomyography transducer.
View Article and Find Full Text PDFBiologic drugs, defined as therapeutic agents produced from or containing components of a living organism, are of growing importance to the pharmaceutical industry. Though oral delivery of medicine is convenient, biologics require invasive injections because of their poor bioavailability via oral routes. Delivery of biologics to the small intestine using electronic delivery with devices that are similar to capsule endoscopes is a promising means of overcoming this limitation and does not require reformulation of the therapeutic agent.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
May 2021
The impact of Pb on the environment and human health and recent restrictions on its use in electronic devices are generating demand for Pb-free piezoelectric materials. Examples are now available commercially, but the full elastic-piezoelectric-dielectric (EPD) matrices needed for device design, including over a range of operating conditions, have not yet been published. The standard IEEE EPD matrix measurement method needs four sample geometries, making it inconvenient and increasing errors.
View Article and Find Full Text PDFInflammation of the gastrointestinal (GI) tract accompanies several diseases, including Crohn's disease. Currently, video capsule endoscopy and deep bowel enteroscopy are the main means for direct visualisation of the bowel surface. However, the use of optical imaging limits visualisation to the luminal surface only, which makes early-stage diagnosis difficult.
View Article and Find Full Text PDFShear-wave elastography may produce misleadingly high values if too much pressure is applied during the imaging process. However, in clinical routine there is presently no way to monitor the pressure applied during the measurements. In this work we introduce a novel measurement setup which can directly be attached to an ultrasonic imaging transducer and allows observation of the applied pressure in real time.
View Article and Find Full Text PDFWireless capsule endoscopy has been used for the clinical examination of the gastrointestinal (GI) tract for two decades. However, most commercially available devices only utilise optical imaging to examine the GI wall surface. Using this sensing modality, pathology within the GI wall cannot be detected.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
January 2020
A complementary metal-oxide-semiconductor (CMOS) application-specific integrated circuit (ASIC) has been developed to generate arbitrary, dynamic phase patterns for acoustic hologram applications. An experimental prototype has been fabricated to demonstrate phase shaping. It comprises a cascadable 1 ×9 array of identical, independently controlled signal generators implemented in a 0.
View Article and Find Full Text PDFDiagnostic endoscopy in the gastrointestinal tract has remained largely unchanged for decades and is limited to the visualization of the tissue surface, the collection of biopsy samples for diagnoses, and minor interventions such as clipping or tissue removal. In this work, we present the autonomous servoing of a magnetic capsule robot for , subsurface diagnostics of microanatomy. We investigated and showed the feasibility of closed-loop magnetic control using digitized microultrasound (μUS) feedback; this is crucial for obtaining robust imaging in an unknown and unconstrained environment.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
October 2019
Lead zirconate titanate (PZT)-based piezoelectric micromachined ultrasonic transducers (PMUTs) for particle manipulation applications were designed, fabricated, characterized, and tested. The PMUTs had a diaphragm diameter of 60 [Formula: see text], a resonant frequency of ~8 MHz, and an operational bandwidth (BW) of 62.5%.
View Article and Find Full Text PDFPrecision metabolomics and quantification for cost-effective rapid diagnosis of disease are the key goals in personalized medicine and point-of-care testing. At present, patients are subjected to multiple test procedures requiring large laboratory equipment. Microelectronics has already made modern computing and communications possible by integration of complex functions within a single chip.
View Article and Find Full Text PDFNat Rev Gastroenterol Hepatol
July 2019
Capsule endoscopy (CE) has proved to be a powerful tool in the diagnosis and management of small bowel disorders since its introduction in 2001. However, white light imaging (WLI) is the principal technology used in clinical CE at present, and therefore, CE is limited to mucosal inspection, with diagnosis remaining reliant on visible manifestations of disease. The introduction of WLI CE has motivated a wide range of research to improve its diagnostic capabilities through integration with other sensing modalities.
View Article and Find Full Text PDFContactless sample confinement would enable a whole host of new studies in developmental biology and neuroscience, in particular, when combined with long-term, wide-field optical imaging. To achieve this goal, we demonstrate a contactless acoustic gradient force trap for sample confinement in light sheet microscopy. Our approach allows the integration of real-time environmentally controlled experiments with wide-field low photo-toxic imaging, which we demonstrate on a variety of marine animal embryos and larvae.
View Article and Find Full Text PDFThe role of technology in healthcare is rapidly evolving. However, it can be argued that gastroenterology has not kept pace with other medical fields due to the multifaceted needs of this speciality and other issues. Innovation in healthcare technology increasingly requires interdisciplinary collaboration between engineers and clinicians.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
August 2018
Prototypes of a PZT-based ultrasound needle-actuating device have shown the ability to reduce needle penetration force and enhance needle visibility with color Doppler imaging during needle insertion for tissue biopsy and regional anesthesia. However, the demand for smaller, lighter devices and the need for high performance transducers have motivated investigation of a different configuration of needle-actuation transducer, utilizing the -mode of PZT4 piezoceramic, and exploration of further improvement in its performance using relaxor-type piezocrystal. This paper outlines the development of the -mode needle actuation transducer design from simulation to fabrication and demonstration.
View Article and Find Full Text PDFClinical endoscopy and colonoscopy are commonly used to investigate and diagnose disorders in the upper gastrointestinal tract and colon, respectively. However, examination of the anatomically remote small bowel with conventional endoscopy is challenging. This and advances in miniaturization led to the development of video capsule endoscopy (VCE) to allow small bowel examination in a noninvasive manner.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
April 2018
Video capsule endoscopy (VCE) has significantly advanced visualization of the gastrointestinal tract since its introduction in the last 20 years. Work is now under way to combine VCE with microultrasound imaging. However, small maximum capsule dimensions, coupled with the electronics required to integrate ultrasound imaging capabilities, pose significant design challenges.
View Article and Find Full Text PDFThis paper describes the design, fabrication, packaging, and performance characterization of a conformal helix antenna created on the outside of a capsule endoscope designed to operate at a carrier frequency of 433 MHz within human tissue. Wireless data transfer was established between the integrated capsule system and an external receiver. The telemetry system was tested within a tissue phantom and in vivo porcine models.
View Article and Find Full Text PDFA biomarker is a measurable indicator of normal biologic processes, pathogenic processes or pharmacological responses. The identification of a useful biomarker is challenging, with several hurdles to overcome before clinical adoption. This review gives a general overview of a range of biomarkers associated with inflammatory bowel disease or colorectal cancer along the gastrointestinal tract.
View Article and Find Full Text PDFVideo capsule endoscopy (VCE) is now a clinically accepted diagnostic modality in which miniaturized technology, an on-board power supply and wireless telemetry stand as technological foundations for other capsule endoscopy (CE) devices. However, VCE does not provide therapeutic functionality, and research towards therapeutic CE (TCE) has been limited. In this paper, a route towards viable TCE is proposed, based on multiple CE devices including important acoustic sensing and drug delivery components.
View Article and Find Full Text PDFVideo capsule endoscopy (VCE) has been of immense benefit in the diagnosis and management of gastrointestinal (GI) disorders since its introduction in 2001. However, it suffers from a number of well recognized deficiencies. Amongst these is the limited capability of white light imaging, which is restricted to analysis of the mucosal surface.
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