Dr. Irving J. Oppenheim Profile

Dr. Irving J. Oppenheim

Professor at Carnegie Mellon Univ

SPIE Involvement:

Author

Publications (38)

Proceedings Article | 22 April 2020 Presentation + Paper

Microparticle sorting with a microfluidic system and ultrasonic standing waves

Emily Chuang, Kelvin Gregory, Irving Oppenheim

Proceedings Volume 11381, 1138114 (2020) https://doi.org/10.1117/12.2558598

KEYWORDS: Particles, Microfluidics, Acoustics, Polymethylmethacrylate, Ultrasonics, Transducers

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Proceedings Article | 29 March 2019 Presentation + Paper

Ultrasonic microparticle alignment and direct ink writing using glass capillaries

Erin Dauson, Kelvin Gregory, Robert Heard, Irving Oppenheim, Stephanie Wong, Cheyney (Chiheng) Zhou

Proceedings Volume 10968, 109680N (2019) https://doi.org/10.1117/12.2515277

KEYWORDS: Transducers, 3D printing, Microfluidics, Ultrasonics, Capillaries, Particles

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Proceedings Article | 22 March 2018 Presentation + Paper

Ultrasonic alignment of microparticles in nozzle-like geometries

Molly Whittaker, Erin Dauson, Jaime Parra-Raad, Robert Heard, Irving Oppenheim

Proceedings Volume 10596, 105960X (2018) https://doi.org/10.1117/12.2296868

KEYWORDS: Acoustics, Microfluidics, Particles, Resonators, Transducers, Ultrasonics, 3D printing, Prisms, Silicon, Polymethylmethacrylate, Piezoelectric driven mechanisms

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Proceedings Article | 20 April 2016 Presentation + Paper

Ultrasonic guided wave detection of scatterers on large clad steel plates

Peng Gong, Joel Harley, Mario Berges, Warren Junker, David Greve, Irving Oppenheim

Proceedings Volume 9803, 98033O (2016) https://doi.org/10.1117/12.2214393

KEYWORDS: Ultrasonics, Waveguides, Signal processing, Corrosion, Defect detection, Inspection, Transducers, Sensors, Error analysis

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Proceedings Article | 20 April 2016 Presentation + Paper

Compensating temperature-induced ultrasonic phase and amplitude changes

Peng Gong, Thomas Hay, David Greve, Warren Junker, Irving Oppenheim

Proceedings Volume 9803, 98033K (2016) https://doi.org/10.1117/12.2218899

KEYWORDS: Ultrasonics, Structural health monitoring, Phase shifts, Wave propagation, Damage detection, Iron, Transducers, Signal attenuation, Performance modeling

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Proceedings Article | 1 April 2016 Presentation + Paper

Mechanically robust microfluidics and bulk wave acoustics to sort microparticles

Erin Dauson, Kelvin Gregory, David Greve, Gregory Healy, Irving Oppenheim

Proceedings Volume 9805, 98051I (2016) https://doi.org/10.1117/12.2214394

KEYWORDS: Microfluidics, Particles, Acoustics, Polymethylmethacrylate, Bacteria, Prisms, Ultrasonics

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Proceedings Article | 27 March 2015 Paper

Volumetric loss quantification using ultrasonic inductively coupled transducers

Peng Gong, Thomas Hay, David Greve, Irving Oppenheim

Proceedings Volume 9435, 943514 (2015) https://doi.org/10.1117/12.2084390

KEYWORDS: Transducers, Ultrasonics, Aluminum, Wave propagation, Receivers, Signal detection, Diffraction, Signal attenuation, Damage detection, Distance measurement

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Proceedings Article | 10 April 2014 Paper

A robust baseline removal method for guided wave damage localization

Chang Liu, Joel Harley, Mario Bergés, David Greve, Warren Junker, Irving Oppenheim

Proceedings Volume 9061, 90611K (2014) https://doi.org/10.1117/12.2045577

KEYWORDS: Waveguides, Ultrasonics, Transducers, Temperature metrology, Wave propagation, Signal processing, Signal to noise ratio, Ferroelectric materials, Aluminum, Damage detection

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Proceedings Article | 8 March 2014 Open Access

Surface acoustic wave action on microfluidic channels and microparticles

Erin Dauson, Kelvin Gregory, David Greve, Irving Oppenheim

Proceedings Volume 9061, 906102 (2014) https://doi.org/10.1117/12.2045556

KEYWORDS: Polymethylmethacrylate, Lithium niobate, Particles, Acoustics, Microfluidics, Semiconducting wafers, Reflection, Epoxies, Wave plates, Aluminum

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Proceedings Article | 8 March 2014 Paper

ASR damage detection in concrete from ultrasonic methods

Peng Gong, Mark Patton, David Greve, Joel Harley, Warren Junker, Chang Liu, Irving Oppenheim

Proceedings Volume 9061, 90610E (2014) https://doi.org/10.1117/12.2045645

KEYWORDS: Signal attenuation, Ultrasonics, Damage detection, Cements, Transducers, Signal detection, Fourier transforms, Chemical reactions, Silica, Nondestructive evaluation

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Proceedings Article | 19 April 2013 Paper

Singular value decomposition for novelty detection in ultrasonic pipe monitoring

Chang Liu, Joel Harley, Yujie Ying, Irving Oppenheim, Mario Bergés, David Greve, James Garrett

Proceedings Volume 8692, 86921R (2013) https://doi.org/10.1117/12.2009891

KEYWORDS: Ultrasonics, Environmental sensing, Waveguides, Temperature metrology, Damage detection, Structural health monitoring, Lithium, Digital filtering, Sensors, Signal processing

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Proceedings Article | 19 April 2013 Paper

Microparticle transport and concentration with surface acoustic waves

Irving Oppenheim, Erin Dauson, David Greve, Kelvin Gregory

Proceedings Volume 8692, 86921D (2013) https://doi.org/10.1117/12.2008936

KEYWORDS: Acoustics, Lithium niobate, Microfluidics, 3D modeling, Electrodes, Instrument modeling, Aluminum, Particles, Glasses, Transducers

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Proceedings Article | 17 April 2013 Paper

A flexible insert for wireless strain sensing

Irving Oppenheim, David Greve, Antonia Chen

Proceedings Volume 8695, 86951Y (2013) https://doi.org/10.1117/12.2008935

KEYWORDS: Sensors, Reflection, Surgery, Titanium, Antennas, Electrodes, Lithium niobate, Solids, Acoustics, Data acquisition

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Proceedings Article | 3 April 2012 Paper

Ultrasonic monitoring of a pipe under operating conditions

Chang Liu, Joel Harley, Nicholas O'Donoughue, Yujie Ying, Martin Altschul, James Garrett, José M. Moura, Irving Oppenheim, Lucio Soibelman

Proceedings Volume 8345, 83450B (2012) https://doi.org/10.1117/12.915040

KEYWORDS: Ultrasonics, Transducers, Signal detection, Environmental sensing, Ferroelectric materials, Received signal strength, Waveguides, Signal processing, Temperature metrology, Receivers

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Proceedings Article | 14 April 2011 Paper

Temperature and stiffness correction of SAW devices for wireless strain sensing

Irving Oppenheim, Nicola Carey, T.-L. Chin, Peng Zheng, David Greve

Proceedings Volume 7981, 79811F (2011) https://doi.org/10.1117/12.880176

KEYWORDS: Sensors, Temperature metrology, Phase measurement, Lithium niobate, Acoustics, Reflection, Electrodes, Biological and chemical sensing, Computer aided design, Semiconducting wafers

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Proceedings Article | 1 April 2010 Paper

Time reversal for damage detection in pipes

Yujie Ying, Joel Harley, James Garrett, Yuanwei Jin, José M. Moura, Nicholas O'Donoughue, Irving Oppenheim, Lucio Soibelman

Proceedings Volume 7647, 76473S (2010) https://doi.org/10.1117/12.847799

KEYWORDS: Waveguides, Transmitters, Transducers, Ferroelectric materials, Ultrasonics, Semiconducting wafers, Inspection, Damage detection, Receivers, Wave propagation

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Proceedings Article | 1 April 2010 Paper

Surface acoustic wave devices for wireless strain measurement

T.-L. Chin, Peng Zheng, Irving Oppenheim, David Greve

Proceedings Volume 7647, 764743 (2010) https://doi.org/10.1117/12.847657

KEYWORDS: Acoustics, Electrodes, Sensors, Semiconducting wafers, Antennas, Lithium niobate, Phase measurement, Wave propagation, Computer aided design, Transducers

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Proceedings Article | 1 April 2010 Paper

Cognitive sensor networks for structure defect monitoring and classification using guided wave signals

Yuanwei Jin, Nicholas O'Donoughue, José M. Moura, Joel Harley, James Garrett, Irving Oppenheim, Lucio Soibelman, Yujie Ying, Lin He

Proceedings Volume 7647, 76473T (2010) https://doi.org/10.1117/12.848893

KEYWORDS: Sensors, Sensor networks, Corrosion, Waveguides, Environmental sensing, Transducers, Wave propagation, Ultrasonics, Phased arrays, Classification systems

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Proceedings Article | 1 April 2010 Paper

Oblique excitation of nearly-longitudinal waves in thick plates

Yujie Ying, Irving Oppenheim, James Garrett, David Greve, Lucio Soibelman

Proceedings Volume 7647, 76474L (2010) https://doi.org/10.1117/12.847783

KEYWORDS: Wave plates, Transducers, Wave propagation, Interfaces, Ultrasonics, Inspection, Computer simulations, Transmitters, Waveguides, Defect detection

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Proceedings Article | 30 March 2009 Paper

Ultrasonic flaw detection in a monorail box beam

Peng Zheng, David Greve, Irving Oppenheim

Proceedings Volume 7292, 729211 (2009) https://doi.org/10.1117/12.815515

KEYWORDS: Transducers, Ultrasonics, Reflection, Receivers, Scattering, Target detection, Acoustic coupling, Wave plates, Prototyping, Data acquisition

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A steel box beam in a monorail application is constructed with an epoxy grout wearing surface, precluding visual inspection of its top flange. This paper describes a sequence of experimental research tasks to develop an ultrasonic system to detect flaws (such as fatigue cracks) in that flange, and the results of a field test to demonstrate system performance. The problem is constrained by the fact that the flange is exposed only along its longitudinal edges, and by the fact that permanent installation of transducers at close spacing was deemed to be impractical. The system chosen for development, after experimental comparison of alternate technologies, features angle-beam ultrasonic transducers with fluid coupling to the flange edge; the emitting transducers create transverse waves that travel diagonally across the width of the flange, where an array of receiving transducers detect flaw reflections and flaw shadows. The system rolls along the box beam, surveying (screening) the top flange for the presence of flaws. In a first research task, conducted on a full-size beam specimen, we compared waves generated from different transducer locations, either the flange edge or the web face, and at different frequency ranges. At relatively low frequencies, such as 100 kHz, we observed Lamb wave modes, and at higher frequency, in the MHz range, we observed nearlylongitudinal waves with trailing pulses. In all cases we observed little attenuation by the wearing surface and little influence of reflection at the web-flange joints. At the conclusion of this task we made the design decision to use edgemounted transducers at relatively high frequency, with correspondingly short wavelength, for best scattering from flaws. In a second research task we conducted experiments at 55% scale on a steel plate, with machined flaws of different size, and detected flaws of target size for the intended application. We then compared the performance of bonded transducers, fluid-coupled transducers, and angle-beam (wedge) transducers; from that comparison we made the design decision to use wedges, which beam the wave to increase the scattering from flaws. We also compared the performance of wired transducers using fluid coupling to that of wireless (inductively coupled) transducers mounted permanently. Although the wireless transducers achieved flaw detection, the necessary spacing (determined experimentally) would have required an impractical number of transducers. Therefore, we made the design decision to use wedge transducers with fluid coupling. In a third research task we developed and tested a rolling system with a water channel for acoustic coupling, including a study of its sensitivity to misalignment, and in a fourth task we devised a data display to create a pattern of reflections or shadows that could be easily interpreted as evidence of a flaw. Finally, we conducted a field test on the full-size system in a region containing bolt holes, which act as a physical simulation of a flaw, and show successful detection of reflections and shadows from those holes.

Proceedings Article | 30 March 2009 Paper

Sensitivity of a MEMS acoustic emission sensor system

Amelia Wright, David Greve, Irving Oppenheim

Proceedings Volume 7292, 72920R (2009) https://doi.org/10.1117/12.815497

KEYWORDS: Sensors, Microelectromechanical systems, Amplifiers, Picture Archiving and Communication System, Signal to noise ratio, Ferroelectric materials, Lead, Indium arsenide, Acoustic emission, Electronics

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Proceedings Article | 8 April 2008 Paper

Lamb waves and nearly-longitudinal waves in thick plates

David Greve, Irving Oppenheim, Peng Zheng

Proceedings Volume 6932, 69321I (2008) https://doi.org/10.1117/12.775919

KEYWORDS: Wave plates, Wave propagation, Transducers, Scattering, Particles, Wavefronts, Edge roughness, Lead, Ultrasonics, Civil engineering

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Proceedings Article | 8 April 2008 Paper

Crack detection with wireless inductively-coupled transducers

Peng Zheng, David Greve, Irving Oppenheim

Proceedings Volume 6932, 69321H (2008) https://doi.org/10.1117/12.775917

KEYWORDS: Transducers, Wave plates, Inductive coupling, Ultrasonics, Ferroelectric materials, Reflection, Semiconducting wafers, Receivers, Sensors, Data acquisition

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Proceedings Article | 8 April 2008 Paper

Design and testing of a MEMS acoustic emission sensor system

David Greve, Irving Oppenheim, Amelia Wright, Wei Wu

Proceedings Volume 6932, 69321P (2008) https://doi.org/10.1117/12.775777

KEYWORDS: Transducers, Sensors, Microelectromechanical systems, Computer aided design, Capacitance, Signal to noise ratio, Acoustic emission, Motion measurement, Ceramics, Laboratory techniques

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Proceedings Article | 18 April 2007 Paper

A wire-guided transducer for acoustic emission sensing

Ian Neill, I. Oppenheim, D. Greve

Proceedings Volume 6529, 652913 (2007) https://doi.org/10.1117/12.715358

KEYWORDS: Transducers, Waveguides, Acoustic emission, Sensors, Ultrasonics, Ferroelectric materials, Signal processing, Semiconducting wafers, Actuators, Wave propagation

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Proceedings Article | 10 April 2007 Paper

Fatigue crack detection in a plate girder using Lamb waves

D. Greve, I. Oppenheim, Wei Wu, Peng Zheng

Proceedings Volume 6529, 65291W (2007) https://doi.org/10.1117/12.715359

KEYWORDS: Transducers, Wave plates, Ultrasonics, Ferroelectric materials, Transmitters, Receivers, Civil engineering, Sensors, Computer engineering, Physics

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Proceedings Article | 6 April 2007 Paper

Development of a MEMS acoustic emission sensor system

David Greve, Irving Oppenheim, Wei Wu, Amelia Wright

Proceedings Volume 6529, 652912 (2007) https://doi.org/10.1117/12.715357

KEYWORDS: Sensors, Microelectromechanical systems, Transducers, Acoustic emission, Ceramics, Computer aided design, Capacitance, Etching, Amplifiers, Acoustic coupling

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An improved multi-channel MEMS chip for acoustic emission sensing has been designed and fabricated in 2006 to create a device that is smaller in size, superior in sensitivity, and more practical to manufacture than earlier designs. The device, fabricated in the MUMPS process, contains four resonant-type capacitive transducers in the frequency range between 100 kHz and 500 kHz on a chip with an area smaller than 2.5 sq. mm. The completed device, with its circuit board, electronics, housing, and connectors, possesses a square footprint measuring 25 mm x 25 mm. The small footprint is an important attribute for an acoustic emission sensor, because multiple sensors must typically be arrayed around a crack location. Superior sensitivity was achieved by a combination of four factors: the reduction of squeeze film damping, a resonant frequency approximating a rigid body mode rather than a bending mode, a ceramic package providing direct acoustic coupling to the structural medium, and high-gain amplifiers implemented on a small circuit board. Manufacture of the system is more practical because of higher yield (lower unit costs) in the MUMPS fabrication task and because of a printed circuit board matching the pin array of the MEMS chip ceramic package for easy assembly and compactness. The transducers on the MEMS chip incorporate two major mechanical improvements, one involving squeeze film damping and one involving the separation of resonance modes. For equal proportions of hole area to plate area, a triangular layout of etch holes reduces squeeze film damping as compared to the conventional square layout. The effect is modeled analytically, and is verified experimentally by characterization experiments on the new transducers. Structurally, the transducers are plates with spring supports; a rigid plate would be the most sensitive transducer, and bending decreases the sensitivity. In this chip, the structure was designed for an order-of-magnitude separation between the first and the second mode frequency, strongly approximating the desirable rigid plate limit. The effect is modeled analytically and is verified experimentally by measurement of the resonance frequencies in the new transducers. Another improvement arises from the use of a pin grid array ceramic package, in which the MEMS chip is acoustically coupled to the structure with only two interfaces, through a ceramic medium that is negligible in thickness when compared to wavelengths of interest. Like other acoustic emission sensors, those on the 2006 MEMS chip are sensitive only to displacements normal to the surface on which the device is mounted. To overcome that long-standing limitation, a new MEMS sensor sensitive to in-plane motion has been designed, featuring a different spring-mass mechanism and creating the signal by the change in capacitance between stationary and moving fingers. Predicted damping is much lower for the case of the in-plane sensor, and squeeze-film damping is used selectively to isolate the desired in-plane mechanical response from any unwanted out-of-plane response. The new spring-mass mechanism satisfies the design rules for the PolyMUMPS fabrication (foundry) process. A 3-D MEMS sensor system is presently being fabricated, collocating two in-plane sensors and one out-of-plane sensor at the mm scale, which is very short compared to the acoustic wavelength of interest for stress waves created by acoustic emission events.

Proceedings Article | 11 April 2006 Paper

Lamb wave behavior in bridge girder geometries

I. Oppenheim, D. Greve, N. Tyson

Proceedings Volume 6174, 61742E (2006) https://doi.org/10.1117/12.643219

KEYWORDS: Wave plates, Reflection, Transducers, Particles, Bridges, Ferroelectric materials, Wave propagation, Optical simulations, Adaptive optics, Waveguides

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Proceedings Article | 5 April 2006 Paper

Structural tests using a MEMS acoustic emission sensor

Irving Oppenheim, David Greve, Didem Ozevin, D. Robert Hay, Thomas Hay, Stephen Pessiki, Nathan Tyson

Proceedings Volume 6174, 617404 (2006) https://doi.org/10.1117/12.648676

KEYWORDS: Transducers, Microelectromechanical systems, Acoustic emission, Sensors, Lead, Picture Archiving and Communication System, Computer aided design, Bridges, Signal detection, Electronics

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In a collaborative project at Lehigh and Carnegie Mellon, a MEMS acoustic emission sensor was designed and fabricated as a suite of six resonant-type capacitive transducers in the frequency range between 100 and 500 kHz. Characterization studies showed good comparisons between predicted and experimental electro-mechanical behavior. Acoustic emission events, simulated experimentally in steel ball impact and in pencil lead break tests, were detected and source localization was demonstrated. In this paper we describe the application of the MEMS device in structural testing, both in laboratory and in field applications. We discuss our findings regarding housing and mounting (acoustic coupling) of the MEMS device with its supporting electronics, and we then report the results of structural testing. In all tests, the MEMS transducers were used in parallel with commercial acoustic emission sensors, which thereby serve as a benchmark and permit a direct observation of MEMS device functionality. All tests involved steel structures, with particular interest in propagation of existing cracks or flaws. A series of four laboratory tests were performed on beam specimens fabricated from two segments (Grade 50 steel) with a full penetration weld (E70T-4 electrode material) at midspan. That weld region was notched, an initial fatigue crack was induced, and the specimens were then instrumented with one commercial transducer and with one MEMS device; data was recorded from five individual transducers on the MEMS device. Under a four-point bending test, the beam displayed both inelastic behavior and crack propagation, including load drops associated with crack instability. The MEMS transducers detected all instability events as well as many or most of the acoustic emissions occurring during plasticity and stable crack growth. The MEMS transducers were less sensitive than the commercial transducer, and did not detect as many events, but the normalized cumulative burst count obtained from the MEMS transducers paralleled the count obtained from the commercial transducer. Waveform analysis of signals from the MEMS transducers provided additional information concerning arrivals of P-waves and S-waves. Similarly, the analysis provided additional confirmation that the acoustic emissions emanated from the damage zone near the crack tip, and were not spurious signals or artifacts. Subsequent tests were conducted in a field application where the MEMS transducers were redundant to a group of commercial transducers. The application example is a connection plate in truss bridge construction under passage of heavy traffic loads. The MEMS transducers were found to be functional, but were less sensitive in their present form than existing commercial transducers. We conclude that the transducers are usable in their current configuration and we outline applications for which they are presently suited, and then we discuss alternate MEMS structures that would provide greater sensitivity.

Proceedings Article | 17 May 2005 Paper

Use of Lamb waves to monitor plates: experiments and simulations

D. Greve, J. Neumann, J. Nieuwenhuis, I. Oppenheim, N. Tyson

Proceedings Volume 5765, (2005) https://doi.org/10.1117/12.599038

KEYWORDS: Transducers, Ferroelectric materials, Wave plates, Semiconducting wafers, Aluminum, Particles, Dispersion, Sensors, Wave propagation, Solids

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Lamb waves at ultrasonic frequencies travel with little attenuation in thin elastic plates, and we demonstrate their use in pulse-echo behavior to monitor plate integrity. We envision using a single PZT wafer-type transducer to generate waves and to receive reflections from distant flaw or boundary locations. However, Lamb waves generally have multiple modes, each of them highly dispersive, and in consequence pulse dispersion can become pronounced and can make difficult or impossible the interpretation of pulse-echo responses. We show that selective generation of the S0 wave will overcome those difficulties; therefore, selection of transducer dimensions and pulse characteristics to achieve selective generation should be considered mandatory for most intended applications. We first review the work of others identifying a basic relationship between transducer dimension and excitation frequency for selective generation of the S0 wave. We then summarize our extensive experimental studies of wafer-type transducers with particular attention to S0 and A0 mode behavior, both in transmission and reception. We next report our two-dimensional finite element simulation of the same problem performed in FEMLAB, requiring transient simulation of the coupled electromechanical problem. We simulate the piezoelectric response of the wafer-type transducer coupled to the elastic plate, both as transmitter and receiver, as well as the development of Lamb waves within the source region and their subsequent propagation along the plate. Simulations illustrate the development and separation of the S0 and A0 modes and reproduce the expected group velocities and dispersion behavior. We show good agreement between our experiments and our simulations regarding S0 mode behavior, and we summarize the results to guide a designer in choosing transducer dimensions. In particular, good selectivity between the S0 and A0 mode generation can be obtained with appropriate choice of transducer size and center frequency. We show the results of experiments on an aluminum plate in which excitation of a single PZT wafer-type transducer at 6.5 V (peak-to-peak) produces reflected signals of ample strength (tens of mV) from distant boundaries and from partial thickness flaws.

Proceedings Article | 17 May 2005 Paper

Design, characterization, and experimental use of the second generation MEMS acoustic emission device

Didem Ozevin, David Greve, Irving Oppenheim, Stephen Pessiki

Proceedings Volume 5765, (2005) https://doi.org/10.1117/12.601161

KEYWORDS: Transducers, Acoustic emission, Microelectromechanical systems, Picture Archiving and Communication System, Capacitance, Signal detection, Lead, Etching, Atmospheric sensing, Surface micromachining

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We describe the design, fabrication, testing and application (in structural experiments) of our 2004 (second generation) MEMS device, designed for acoustic emission sensing based upon experiments with our 2002 (first generation) device. Both devices feature a suite of resonant-type transducers in the frequency range between 100 kHz and 1 MHz. The 2002 device was designed to operate in an evacuated housing because of high squeeze film damping, as confirmed in our earlier experiments. In additional studies involving the 2002 device, experimental simulation of acoustic emissions in a steel plate, using pencil lead break or ball impact loading, showed that the transducers in the frequency range of 100 kHz-500 kHz presented clearer output signals than the transducers with frequencies higher than 500 kHz. Using the knowledge gained from the 2002 device, we designed and fabricated our second generation device in 2004 using the multi-user polysilicon surface micromachining (MUMPs) process. The 2004 device has 7 independent capacitive type transducers, compared to 18 independent transducers in the 2002 device, including 6 piston type transducers in the frequency range of 100 kHz to 500 kHz and 1 piston type transducer at 1 MHz to capture high frequency information. Piston type transducers developed in our research have two uncoupled modes so that twofold information can be acquired from a single transducer. In addition, the piston shape helps to reduce residual stress effect of surface micromachining process. The center to center distance between etch holes in the vibrating plate was reduced from 30 μm to 13 μm, in order to reduce squeeze film damping. As a result, the Q factor under atmospheric pressure for the 100 kHz transducer was increased to 2.37 from 0.18, and therefore the vacuum housing has been eliminated from the 2004 device. Sensitivities of transducers were also increased, by enlarging transducer area, in order to capture significant small amplitude acoustic emission events. The average individual transducer area in the 2004 device was increased to 6.97 mm² as compared to 2.51 mm² in the 2002 device. In this paper, we report the new experimental results on the characterization of the 2004 device and compare them with analytical results. We show improvements in sensitivity as measured by capacitance and as measured by pencil lead break experiments. Improvement in damping is also evaluated by admittance measurement in atmosphere. Pencil lead break experiments also show that transducers can operate in atmospheric pressure. Finally, we apply the device to acoustic emission experiments on crack propagation in a steel beam specimen, precracked in fatigue, in a four-point bending test.

Proceedings Article | 29 July 2004 Paper

Resonant-type MEMS transducers excited by two acoustic emission simulation techniques

Didem Ozevin, David Greve, Irving Oppenheim, Stephen Pessiki

Proceedings Volume 5391, (2004) https://doi.org/10.1117/12.539538

KEYWORDS: Transducers, Acoustic emission, Microelectromechanical systems, Lead, Time-frequency analysis, Fourier transforms, Signal detection, Surface micromachining, Signal processing, Ceramics

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Proceedings Article | 29 July 2004 Paper

Comparison of piezoresistive and capacitive ultrasonic transducers

John Neumann, David Greve, Irving Oppenheim

Proceedings Volume 5391, (2004) https://doi.org/10.1117/12.539560

KEYWORDS: Sensors, Transducers, Ultrasonics, Piezoresistive sensors, Silicon, Capacitance, Microelectromechanical systems, Electrodes, Bridges, Resistors

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Proceedings Article | 18 August 2003 Paper

Experiments in ultrasonic flaw detection using a MEMS transducer

Akash Jain, David Greve, Irving Oppenheim

Proceedings Volume 5057, (2003) https://doi.org/10.1117/12.482382

KEYWORDS: Transducers, Microelectromechanical systems, Signal detection, Silicon, Ultrasonics, Solids, Phased arrays, Acoustics, Ferroelectric materials, Capacitance

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Proceedings Article | 18 August 2003 Paper

Development of a MEMS device for acoustic emission testing

Didem Ozevin, Stephen Pessiki, Akash Jain, David Greve, Irving Oppenheim

Proceedings Volume 5057, (2003) https://doi.org/10.1117/12.482383

KEYWORDS: Transducers, Microelectromechanical systems, Acoustic emission, Ultrasonics, Sensors, Signal detection, Capacitance, Amplifiers, Receivers, Scanning electron microscopy

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Proceedings Article | 18 August 2003 Paper

Energy scavenging for sensor applications using structural strains

Joshua Ayers, David Greve, Irving Oppenheim

Proceedings Volume 5057, (2003) https://doi.org/10.1117/12.482377

KEYWORDS: Ferroelectric materials, Capacitors, Sensors, Dielectrics, Matrices, Crystals, Capacitance, Diodes, Americium, Ceramics

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Proceedings Article | 28 June 2002 Paper

Developments in chlorine detection in concrete using NMR

Andrew Yun, Mark Patton, James Garrett, Gary Fedder, Kevin Frederick, Jung-Jiin Hsu, Irving Lowe, Irving Oppenheim, Paul Sides

Proceedings Volume 4696, (2002) https://doi.org/10.1117/12.472568

KEYWORDS: Signal to noise ratio, Chlorine, Magnetism, Cements, Sensors, Corrosion, Signal detection, Magnetic sensors, Ions, Sodium

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Proceedings Article | 28 June 2002 Paper

MEMS ultrasonic transducer for monitoring of steel structures

Akash Jain, David Greve, Irving Oppenheim

Proceedings Volume 4696, (2002) https://doi.org/10.1117/12.472561

KEYWORDS: Transducers, Microelectromechanical systems, Signal detection, Sensors, Ultrasonics, Phased arrays, Signal processing, Ferroelectric materials, Capacitance, Inspection

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Showing 5 of 38 publications

Conference Committee Involvement (17)