Publications related to Ultrasonic transducer

Laser Doppler Vibrometer measurements of the 3D pressure field for the estimation of the radiation force produced by an acoustic standing-wave levitator

Acoustic levitation devices use powerful ultrasonic standing waves to levitate objects in mid-air. We have created a system and method to measure the full harmonic content of the acoustic field accurately. Our study revealed that levitated particles alter ...

Elsevier Science Sa2024

Inverse Problems in Pulse-Echo Ultrasound: Exploiting Coherence for Image Enhancement and Quantitative Imaging

Samuel Denys Beuret

Whereas pulse-echo ultrasound imaging relied on focused acoustic waves since its inception, the last two decades have seen the development of techniques based on unfocused waves, including ultrafast ultrasound imaging. In large part due to the emergence of ...

EPFL2024

Optothermal shaping of lamb waves with square and spiral phase fronts

Romain Christophe Rémy Fleury, Aleksi Antoine Bossart, Janez Rus

We introduce a Lamb-wave medium with tunable propagation velocities, which are controlled by a two-dimensional heating pattern produced by a laser beam. We utilized it to demonstrate that waves in an appropriately designed medium can propagate in the form ...

2024

Laser-based ultrasound inspection system

Romain Christophe Rémy Fleury, Janez Rus

A laser-based ultrasound inspection system comprising an object for inspection (1), a laser device for ultrasound generation (3a), a laser device for ultrasound detection (3b), and a coating arrangement (4) including a laser absorbing layer (4a) disposed o ...

2024

Ultrasound inspection training system

Romain Christophe Rémy Fleury, Janez Rus

An ultrasound inspection training system comprising a test object (1), an ultrasound producing device (3) configured to generate ultrasonic signals in the test object and read ultrasonic response signals emitted from the test object, a property altering de ...

2024

Combined Passive and Active Ultrasonic Stress Wave Monitoring of UHPFRC Properties on a Structural Level

Eugen Brühwiler, Numa Joy Bertola, Thomas Schumacher

Ultra-High-Performance Fiber-Reinforced Cementitious Composite (UHPFRC) is becoming popular in designing lightweight and durable structures. UHPFRC structural elements remain crack-free and waterproof under service conditions, significantly improving durab ...

2023

Acoustic Levitation apparatus (Robotics Practicals)

Mahmut Selman Sakar, Lorenzo Francesco John Noseda, Amit Yedidia Dolev, Bora Yalcin

The following data contain the information and files, which are required to recreate and build the experimental setup that is described in the Laboratory manual. Further details can be found in the associated publication “A graduate laboratory experiment t ...

Zenodo2023

Broadband Air-Coupled Ultrasound Emitter and Receiver Enable Simultaneous Measurement of Thickness and Speed of Sound in Solids

Janez Rus

Air-coupled ultrasound sensors have advantages over contact ultrasound sensors when a sample should not become contaminated or influenced by the couplant or the measurement has to be a fast and automated inline process. Thereby, air-coupled transducers mus ...

MDPI2023

Cardiovascular monitoring system

Marco Mattavelli, Catherine Dehollain, Diego Ruben Barrettino, Kerim Türe, Mustafa Besirli

A cardiovascular monitoring system for measuring at least cardiac output comprises an implantable unit (2) configured for placement in a section of artery of a patient and a portable external unit (1) configured for mounting against or close to a patient's ...

2022

Polydimethylsiloxane microstructure-induced acoustic streaming for enhanced ultrasonic DNA fragmentation on a microfluidic chip

Martinus Gijs, Thomas Lehnert, Lin Sun

Next-generation sequencing (NGS) is an essential technology for DNA identification in genomic research. DNA fragmentation is a critical step for NGS and doing this on-chip is of great interest for future integrated genomic solutions. Here we demonstrate fa ...

ROYAL SOC CHEMISTRY2022

Design and Simulation of a Wide-Bandwidth CMUTs Array with Dual-Mixed radii and Multi Operating Modes

Yu Bai, Yihe Zhao, Zhengwen Jiang, Jie Li, Zichen Liu

A capacitive micromachined ultrasonic transducers (CMUTs) array with dual-mixed radii is designed to improve bandwidth and realize multi-modes operating for immersed ultrasonic applications. The two-size (TS) CMUT array is composed of two sub-arrays with d ...

IEEE2021

Progress on Tests on Splices Between Nb3Sn Rutherford Cables for Graded High-Field Accelerator Magnets

Pierluigi Bruzzone, Mithlesh Kumar, Vincenzo D'Auria

Future high-field accelerator magnets foresee the extensive use of Nb3Sn, more expensive than the Nb-Ti of LHC. For projects involving the series production of magnets, conductor grading is mandatory in order to reduce the cost. To allow grading ...

IEEE Institute of Electrical and Electronics Engineers2021

Directional Cross-Correlation for Improved Aberration Phase Estimation in Pulse-Echo Speed-of-Sound Imaging

Jean-Philippe Thiran, Samuel Denys Beuret, Simon Canales

There has been a recent surge in methods targeting the recovery of a speed-of-sound map from pulse-echo ultrasound measurements. We focused in this work on a particular technique and identified a drawback shared by similar methods - namely the necessity of ...

IEEE2021

A modeling framework to understand and optimize ultrasound neuromodulation

Théo Lemaire

Over the last decade, Low Intensity Focused Ultrasound Stimulation (LIFUS) has emerged as an attractive technology to modulate the activity of deep neural targets without invasive procedures. However, the underlying mechanisms by which ultrasonic waves can ...

EPFL2021

Acoustic emission and ultrasonic testing for fatigue damage detection in a RC bridge deck slab

Eugen Brühwiler, Imane Bayane

There is a significant need to examine precisely the conditions of concrete road bridges because of the increasing traffic and axle loads and the fact that most existing bridges were not designed with respect to fatigue. In-situ investigations are challeng ...

2019

Fully Fdm 3D Printed Flexible Capacitive And Resistive Transducers

Danick Briand, Ryan Mitchell van Dommelen, Xavier Aeby

This work shows the feasibility of fully Fused-Deposition-Modeling (FDM) printed capacitive and resistive transducers, processed in a single tool. It enables their cost-effective processing and provides a simple approach for sensors manufacturing in 3D pri ...

IEEE2019

Vibration Mode of MEMS Ultrasonic Sensors on Buckled Diaphragms with Piezoelectric Resonance Frequency Modification

Paul Muralt, Kaoru Yamashita

Vibration mode and resonance frequency of piezoelectric MEMS ultrasonic sensors was investigated on buckled diaphragm structures. The buckling of the diaphragms was introduced intrinsically through residual stress control of the piezoelectric film, and ext ...

IEEE2019

Phonon-Driven Selective Modulation of Exciton Oscillator Strengths in Anatase TiO2Nanoparticles

Majed Chergui, Edoardo Baldini, Tania Palmieri, Enrico Pomarico, Thomas Charles Henry Rossi, Malte Oppermann, Gerald Auböck

The way nuclear motion affects electronic responses has become a very hot topic in materials science. Coherent acoustic phonons can dynamically modify optical, magnetic, and mechanical properties at ultrasonic frequencies, with promising applications as se ...

American Chemical Society (ACS)2018

Local Structural Heterogeneity and Electromechanical Responses of Ferroelectrics: Learning from Relaxor Ferroelectrics

Dragan Damjanovic

Long-range ordering of dipoles is a key microscopic signature of ferroelectrics. These ordered dipoles form ferroelectric domains, which can be reoriented by electric fields. Relaxor ferroelectrics are a type of ferroelectric where the longrange ordering o ...

2018

A compressed-sensing approach for ultrasound imaging

Jean-Philippe Thiran, Yves Wiaux, Dimitris Perdios, Rafael Eduardo Carrillo Rangel, Marcel Arditi, Adrien Georges Jean Besson

Ultrasonography uses multiple piezo-electric element probes to image tissues. Current time-domain beamforming techniques require the signal at each transducer-element to be sampled at a rate higher than the Nyquist criterion, resulting in an extensive amou ...

2017