Journal articles: 'Acoustic Wave Sensors'

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Sun, Huojiao, Jie Wang, Zong Xu, Ke Tang, and Wanyi Li. "Transverse vibration modes analysis and acoustic response in optical fibers." AIP Advances 13, no. 2 (February 1, 2023): 025047. http://dx.doi.org/10.1063/5.0134559.

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Fiber optic sensors are often used as acoustic sensors to detect sound waves because of their apparent advantages, such as anti-electromagnetic interference and strong adaptation to the environment. The transverse vibration mode of the fiber caused by the acoustic wave can be obtained, and the principle of the optical fiber sensor to detect the acoustic wave signal was explored by using a simple model. It is found that the acoustic wave can effectively cause the change in birefringence of the fiber only when the number of azimuthal modes is 2, and the acoustic wave was detected by using a fiber sensor. It is found, by analyzing the detection mechanism, that the spectral width is proportional to the acoustic impedance of the surrounding medium, and the acoustic interaction between the TR22 mode and the surrounding medium is much weaker than that of the TR21 mode. This provides a theoretical basis for the detection of acoustic signals by fiber optic sensors.

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Dierkes, M., and U. Hilleringmann. "Telemetric surface acoustic wave sensor for humidity." Advances in Radio Science 1 (May 5, 2003): 131–33. http://dx.doi.org/10.5194/ars-1-131-2003.

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Abstract. Surface acoustic wave sensors consist of a piezoelectric substrate with metal interdigital transducers (IDT) on top. The acoustic waves are generated on the surface of the substrate by a radio wave, as it is well known in band pass filters. The devices can be used as wireless telemetric sensors for temperature and humidity, transmitting the sensed signal as a shift of the sensor’s resonance frequency.

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Feng, Yang, Haoda Yu, Wenbo Liu, Keyong Hu, Shuifa Sun, Zhen Yang, and Ben Wang. "Grooving and Absorption on Substrates to Reduce the Bulk Acoustic Wave for Surface Acoustic Wave Micro-Force Sensors." Micromachines 15, no. 5 (May 9, 2024): 637. http://dx.doi.org/10.3390/mi15050637.

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Improving measurement accuracy is the core issue with surface acoustic wave (SAW) micro-force sensors. An electrode transducer can stimulate not only the SAW but also the bulk acoustic wave (BAW). A portion of the BAW can be picked up by the receiving transducer, leading to an unwanted or spurious signal. This can harm the device’s frequency response characteristics, thereby potentially reducing the precision of the micro-force sensor’s measurements. This paper examines the influence of anisotropy on wave propagation, and it also performs a phase-matching analysis between interdigital transducers (IDTs) and bulk waves. Two solutions are shown to reduce the influence of BAW for SAW micro sensors, which are arranged with acoustic absorbers at the ends of the substrate and in grooving in the piezoelectric substrate. Three different types of sensors were manufactured, and the test results showed that the sidelobes of the SAW micro-force sensor could be effectively inhibited (3.32 dB), thereby enhancing the sensitivity and performance of sensor detection. The SAW micro-force sensor manufactured using the new process was tested and the following results were obtained: the center frequency was 59.83 MHz, the fractional bandwidth was 1.33%, the range was 0–1000 mN, the linearity was 1.02%, the hysteresis was 0.59%, the repeatability was 1.11%, and the accuracy was 1.34%.

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Liu, Fen, Rui Guo, Xiujuan Lin, Xiaofang Zhang, Shifeng Huang, Feng Yang, and Xin Cheng. "Influence of Propagation Distance on Characteristic Parameters of Acoustic Emission Signals in Concrete Materials Based on Low-Frequency Sensor." Advances in Civil Engineering 2022 (June 6, 2022): 1–14. http://dx.doi.org/10.1155/2022/7241535.

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Acoustic emission is a nondestructive testing technology based on the propagation of transient elastic waves captured by acoustic emission sensors. The acoustic emission signal depends not only on the distance and quality of the propagation path of the transient elastic wave but also on the sensitivity and frequency bandwidth of the receiving sensor that converts the transient elastic wave into a voltage signal. The frequency range of damage signals in concrete materials is generally in the low-frequency band. If high-frequency sensors are used, the low sensitivity to low-frequency signals will cause measurement errors, while the bandwidth of general commercial acoustic emission sensors is relatively narrow. Therefore, a high-sensitivity, low-frequency acoustic emission sensor is proposed, whose bandwidth is almost four times that of commercial sensors. Based on the customized sensor, we quantitatively analyzed the influence of propagation distance on the characteristic parameters of acoustic waves propagating in concrete. The results show that the different propagation modes of acoustic waves in concrete have different attenuation with the propagation distance, related to the position relationship between the acoustic source and the sensor and the propagation path and path quality. This result gives us a better understanding of the propagation mechanism of acoustic emission signals in concrete materials.

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Grate, Jay W., and Gregory C. Frye. "Acoustic Wave Sensors." Sensors Update 2, no. 1 (October 1996): 37–83. http://dx.doi.org/10.1002/1616-8984(199610)2:1<37::aid-seup37>3.0.co;2-f.

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Dbibih, Fatima-Ezzahraa, Meddy Vanotti, Valerie Soumann, Jean-Marc Cote, Lyes Djoumi, and Virginie Blondeau-Patissier. "Measurement of PM10 and PM2.5 Using SAW Sensors-Based Rayleigh Wave and Love Wave." Engineering Proceedings 6, no. 1 (May 17, 2021): 81. http://dx.doi.org/10.3390/i3s2021dresden-10129.

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Particulate matter (PM) is reported to be dangerous and can cause respiratory and health issues. Regulations, based on PM concentration, have been implemented to limit human exposition to air pollution. An innovative system with surface acoustic wave (SAW) sensors combined with a 3 Lpm cascade impactor was developed by our team for real time mass concentration measurements. In this study, we compare the PM sensitivity of two types of SAW sensors. The first one consists of delay lines based on Rayleigh waves propagating on a Lithium Niobate Y-X 128° substrate. The second one is a based-on Love waves on AT-Quartz. Aerosols were generated from NaCl for PM2.5 and from Silicon carbide for PM10. The sensors’ responses was compared to a reference sensor based on optical measurements. The sensitivity of the Rayleigh wave-based sensor is clearly lower than the Love wave sensor for both PMs. Although less sensitive, Rayleigh wave sensors remain very promising for the development of self-cleaning sensors using RF power due to their high electromechanical factor. To check the performance of our system in real conditions, we tested the sensitivity to PM from cigarette smoke using Rayleigh SAW. The PM2.5 stage showed a phase shift while the PM10 did not respond. This result agrees with previous studies which reported that the size of particles from cigarette smoke varies between 0.1 to 1.5 µm. A good correlation between the reference sensor’s response and the phase variation of SAW sensors was obtained.

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Shiokawa, Showko, and Jun Kondoh. "Surface Acoustic Wave Sensors." Japanese Journal of Applied Physics 43, no. 5B (May 28, 2004): 2799–802. http://dx.doi.org/10.1143/jjap.43.2799.

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Drafts, B. "Acoustic wave technology sensors." IEEE Transactions on Microwave Theory and Techniques 49, no. 4 (April 2001): 795–802. http://dx.doi.org/10.1109/22.915466.

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Cheeke, J. D. N., and Z. Wang. "Acoustic wave gas sensors." Sensors and Actuators B: Chemical 59, no. 2-3 (October 1999): 146–53. http://dx.doi.org/10.1016/s0925-4005(99)00212-9.

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Sinha, Bikash K., and Michel Gouilloud. "Surface acoustic wave sensors." Journal of the Acoustical Society of America 78, no. 5 (November 1985): 1932. http://dx.doi.org/10.1121/1.392695.

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Länge, Kerstin. "Bulk and Surface Acoustic Wave Sensor Arrays for Multi-Analyte Detection: A Review." Sensors 19, no. 24 (December 6, 2019): 5382. http://dx.doi.org/10.3390/s19245382.

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Bulk acoustic wave (BAW) and surface acoustic wave (SAW) sensor devices have successfully been used in a wide variety of gas sensing, liquid sensing, and biosensing applications. Devices include BAW sensors using thickness shear modes and SAW sensors using Rayleigh waves or horizontally polarized shear waves (HPSWs). Analyte specificity and selectivity of the sensors are determined by the sensor coatings. If a group of analytes is to be detected or if only selective coatings (i.e., coatings responding to more than one analyte) are available, the use of multi-sensor arrays is advantageous, as the evaluation of the resulting signal patterns allows qualitative and quantitative characterization of the sample. Virtual sensor arrays utilize only one sensor but combine it with enhanced signal evaluation methods or preceding sample separation, which results in similar results as obtained with multi-sensor arrays. Both array types have shown to be promising with regard to system integration and low costs. This review discusses principles and design considerations for acoustic multi-sensor and virtual sensor arrays and outlines the use of these arrays in multi-analyte detection applications, focusing mainly on developments of the past decade.

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Huang, Jian, Yuanyuan Li, Bei Jiang, and Le Cao. "Analysis of measurement uncertainty of a surface acoustic wave micro-pressure sensor." Measurement and Control 52, no. 1-2 (January 2019): 116–21. http://dx.doi.org/10.1177/0020294018819554.

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As an important support for test and control projects, sensor’s performance is directly related to the accuracy of the measurement. To fully analyze the sources of measurement uncertainty for a surface acoustic wave micro-pressure sensor, in this study the Monte Carlo method and Guide to the Expression of Uncertainty in Measurement to evaluate measurement uncertainty of sensors are used, the sensing experiment was conducted and the measurement addition model was established. We determined the source of measurement uncertainty for a surface acoustic wave micro-pressure sensor. The results show that the Monte Carlo method can obtain a more reliable and accurate inclusion interval in the measurement uncertainty evaluation of a surface acoustic wave micro-pressure sensor.

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Li, Qing, Qi Yin Shi, Zhi Yu Jin, Fan Yang, and Bao Bing Liu. "Study on Self Judgment of Location Lave Speed of Acoustic Emission on Concrete Members." Applied Mechanics and Materials 578-579 (July 2014): 1118–24. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.1118.

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The wave speed of acoustic emission in the medium is uncertain, which is influenced by the source characteristics and the relative position between the acoustic emission source and the sensors. Due to this difference, the results of TDOA location method determination of wave speed in advance are very discrete. As to liner location ,the more farther the distance between two acoustic emission source sensor are, the more serious the discrete error are. Any of the two sensors, a location line can be obtained by setting the wave speed as a horizontal coordinate and the location as the vertical coordinate. The horizontal coordinate of location line of the different sensors is the real wave speed of acoustic emission events. This method has lower computational complexity, which can overcome the influence on acoustic emission location which wave speed setting error brings, having some practical value in Engineering.

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Smirnov, Andrey, Vladimir Anisimkin, Elizaveta Shamsutdinova, Maria-Assunta Signore, Luca Francioso, Kirill Zykov, Vladimir Baklaushev, and Iren Kuznetsova. "Acoustic Waves in Piezoelectric Layered Structure for Selective Detection of Liquid Viscosity." Sensors 23, no. 17 (August 22, 2023): 7329. http://dx.doi.org/10.3390/s23177329.

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The acoustic waves of higher orders propagating in a layered structure consisting of a silicon plate coated with piezoelectric ZnO and/or AlN films were used for the development of a sensor with selective sensitivity to liquid viscosity η in the range of 1–1500 cP. In that range, this sensor possessed low sensitivity to liquid conductivity σ and temperature T in the ranges of 0–2 S/m and 0–55 °C, respectively. The amplitude responses insensitive to the temperature instead of the phase were used to provide the necessary selectivity. The sensor was based on a weak piezoactive acoustic wave of higher order. The volume of the probes sufficient for the measurements was about 100 μL. The characteristics of the sensors were optimized by varying the thicknesses of the structure layers, number of layers, wavelength, wave propagation direction, and the order of the acoustic waves. It was shown that in the case of the layered structure, it is possible to obtain practically the same selective sensitivity toward viscosity as for acoustic waves in pure ST, X quartz. The most appropriate waves for this purpose are quasi-longitudinal and Lamb waves of higher order with in-plane polarization. It was found that for various ranges of viscosity η = 1–20 cP, 20–100 cP, and 100–1500 cP, the maximum sensitivity of the appropriate wave is equal to 0.26 dB/cP, 0.087 dB/cP, and 0.013 dB/cP, respectively. The sensitivity of the waves under study toward the electric conductivity of the liquid is much less than the sensitivity to liquid viscosity. These two responses become comparable only for very small η < 2 cP. The waves investigated have shown no temperature responses in contact with air, but in the presence of liquid, they increase depending on liquid properties. The temperature dependence of liquid viscosity is measurable by the same sensors. The results obtained have shown the possibility of designing acoustic liquid viscosity sensors based on multilayered structures. The set of possible acoustic waves in layered structures possesses modified propagation characteristics (various polarization, phase velocities, electromechanical coupling coefficients, and attenuations). It allows choosing an optimal acoustic wave to detect liquid viscosity only.

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Voinova, Marina V. "On Mass Loading and Dissipation Measured with Acoustic Wave Sensors: A Review." Journal of Sensors 2009 (2009): 1–13. http://dx.doi.org/10.1155/2009/943125.

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We summarize current trends in the analysis of physical properties (surface mass density, viscosity, elasticity, friction, and charge) of various thin films measured with a solid-state sensor oscillating in a gaseous or liquid environment. We cover three different types of mechanically oscillating sensors: the quartz crystal microbalance with dissipation (QCM-D) monitoring, surface acoustic wave (SAW), resonators and magnetoelastic sensors (MESs). The fourth class of novel acoustic wave (AW) mass sensors, namely thin-film bulk acoustic resonators (TFBARs) on vibrating membranes is discussed in brief. The paper contains a survey of theoretical results and practical applications of the sensors and includes a comprehensive bibliography.

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Sheng, Yue, and Kai Yang. "Automatic Correction System Design for English Pronunciation Errors Assisted by High-Sensitivity Acoustic Wave Sensors." Journal of Sensors 2021 (October 26, 2021): 1–12. http://dx.doi.org/10.1155/2021/2853056.

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For correction system of English pronunciation errors, the level of correction performance and the reliability, practicability, and adaptability of information feedback are the main basis for evaluating its excellent comprehensive performance. In view of the disadvantages of traditional English pronunciation correction systems, such as failure to timely feedback and correct learners’ pronunciation errors, slow improvement of learners’ English proficiency, and even misleading learners, it is imperative to design a scientific and efficient automatic correction system for English pronunciation errors. High-sensitivity acoustic wave sensors can identify English pronunciation error signal and convert the dimension of collected pronunciation signal according to channel configuration information; acoustic wave sensors can then assist the automatic correction system of English pronunciation errors to filter out interference components in output signal, analyze real-time spectrum, and evaluate the sensitivity of the acoustic wave sensor. Therefore, on the basis of summarizing and analyzing previous research works, this paper expounds the current research status and significance of the design of automatic correction system for English pronunciation errors, elaborates the development background, current status and future challenges of high-sensitivity acoustic wave sensor technology, introduces the methods and principles of time-domain signal amplitude measurement and pronunciation signal preprocessing, carries out the optimization design of pronunciation recognition sensors, performs the improvement design of pronunciation recognition processors, proposes the hardware design of automatic correction system for English pronunciation errors based on the assistance of high-sensitivity acoustic wave sensors, analyzes the acquisition program design for English pronunciation errors, implements the parameter extraction of English pronunciation error signal, discusses the software design of automatic correction system for English pronunciation errors based on the assistance of high-sensitivity sound wave sensor, and finally, conducts system test and its result analysis. The study results show that the automatic correction system of English pronunciation errors assisted by the high-sensitivity acoustic wave sensors can realize the automatic correction of the amplitude linearity, sensitivity, repeatability error, and return error of English pronunciation errors, which has the robust functions of automatic real-time data collection, processing, saving, query, and retesting. The system can also minimize external interference and improve the accuracy of acoustic wave sensors’ sensitivity calibration, and it provides functions such as reading and saving English pronunciation error signals and visual operation, which effectively improves the ease of use and completeness of the correction system. The study results in this paper provide a reference for the further researches on the automatic correction system design for English pronunciation errors assisted by high-sensitivity acoustic wave sensors.

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Ishido, Masahiro. "Acoustic-wave-based voltage sensors." Sensors and Actuators A: Physical 44, no. 3 (September 1994): 183–89. http://dx.doi.org/10.1016/0924-4247(94)00803-5.

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Khlebarov, Zdravko P., Any I. Stoyanova, and Diana I. Topalova. "Surface acoustic wave gas sensors." Sensors and Actuators B: Chemical 8, no. 1 (April 1992): 33–40. http://dx.doi.org/10.1016/0925-4005(92)85005-h.

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Bashkov, O. V., H. Khon, V. I. Zaikov, I. O. Bashkov, and A. I. Evstigneev. "On-Line Registration of Damages in Composite Materials with Fiber-Optic Acoustic Emission Sensors." Materials Science Forum 946 (February 2019): 270–75. http://dx.doi.org/10.4028/www.scientific.net/msf.946.270.

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This paper presents the results of the analysis of acoustic emission signals registered by using fiber-optic sensors during the propagation of ultrasonic waves in a polymer composite material. Fiber-optical sensors for acoustic emission were constructed according to the scheme of an adaptive holographic interferometer. Unlike piezoelectric sensors, fiber-optic sensors are distributed type sensors. This imposes certain features on the detection of signals in plates in which fiber-optic sensors are embedded. It is established that the difference of the spectrum of acoustic emission signals is registered in different directions of wave propagation. The local maximums of the spectrum are determined by the mode of wave propagation in the plate in different directions and the location of fiber-optic sensors.

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Allen, Luke R., Sandra E. Yuter, Matthew A. Miller, and Laura M. Tomkins. "Objective identification of pressure wave events from networks of 1 Hz, high-precision sensors." Atmospheric Measurement Techniques 17, no. 1 (January 10, 2024): 113–34. http://dx.doi.org/10.5194/amt-17-113-2024.

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Abstract. Mesoscale pressure waves, including atmospheric gravity waves, outflow and frontal passages, and wake lows, are outputs of and can potentially modify clouds and precipitation. The vertical motions associated with these waves can modify the temperature and relative humidity of air parcels and thus yield potentially irreversible changes to the cloud and precipitation content of those parcels. A wavelet-based method for identifying and tracking these types of wave signals in time series data from networks of low-cost, high-precision (0.8 Pa noise floor, 1 Hz recording frequency) pressure sensors is demonstrated. Strong wavelet signals are identified using a wave-period-dependent (i.e., frequency-dependent) threshold, and then those signals are extracted by inverting the wavelet transform. Wave periods between 1 and 120 min were analyzed – a range which could capture acoustic, acoustic-gravity, and gravity wave modes. After extracting the signals from a network of pressure sensors, the cross-correlation function is used to estimate the time difference between the wave passage at each pressure sensor. From those time differences, the wave phase velocity vector is calculated using a least-squares fit. If the fitting error is sufficiently small (thresholds of RMSE < 90 s and NRMSE < 0.1 were used), then a wave event is considered robust and trackable. We present examples of tracked wave events, including a Lamb wave caused by the Hunga Tonga volcanic eruption in January 2020, a gravity wave train, an outflow boundary passage, a frontal passage, and a cold front passage. The data and processing techniques presented here can have research applications in wave climatology and testing associations between waves and atmospheric phenomena.

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Ono, Kanji. "Rayleigh Wave Calibration of Acoustic Emission Sensors and Ultrasonic Transducers." Sensors 19, no. 14 (July 16, 2019): 3129. http://dx.doi.org/10.3390/s19143129.

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Acoustic emission (AE) sensors and ultrasonic transducers were characterized for the detection of Rayleigh waves (RW). Small aperture reference sensors were characterized first using the fracture of glass capillary tubes in combination with a theoretical displacement calculation, which utilized finite element method (FEM) and was verified by laser interferometer. For the calibration of 18 commercial sensors and two piezoceramic disks, a 90° angle beam transducer was used to generate RW pulses on an aluminum transfer block. By a substitution method, RW receiving sensitivity of a sensor under test was determined over the range of frequency from 22 kHz to 2 MHz. Results were compared to the sensitivities to normally incident waves (NW) and to other guided waves (GW). It was found that (1) NW sensitivities are always higher than RW sensitivities, (2) differences between NW and RW receiving sensitivities are dependent on frequency and sensor size, (3) most sensors show comparable RW and GW receiving sensitivities, especially those of commonly used AE sensors, and (4) the receiving sensitivities of small aperture (1 mm diameter) sensors behave differently from larger sensors.

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Shevelko, Michail, Andrey Lutovinov, Aleksandr Peregudov, Ekaterina Popkova, Yasemin Durukan, and Sergey Shevchenko. "The Sensitive Element of Acoustic Sensor on Circular Polarized Waves: From Theoretical Considerations towards Perspective Rotation Rate Sensors Design." Sensors 21, no. 1 (December 23, 2020): 32. http://dx.doi.org/10.3390/s21010032.

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In this paper, the perspectives of using the features of acoustic wave propagation to design rotation rate sensors (RRS) are discussed. The possibility of developing the solid-state sensitive elements (SE) of RRS on acoustic waves of circular polarization is shown. The theoretical basis of bulk acoustic wave propagation under rotation is given. The direct excitation of circularly polarized acoustic wave (CPAW) is considered, the design of the CPAW emitting transducer is offered. The results of experimental studies that indicated the circular nature of the particle motions in the radiated wave are discussed. The principally new concept of the RRS SE design on CPAW, being able to operate under high vibration and acceleration, is proposed. The experimental results revealed a high correlation with theoretical and numerical predictions and confirmed RRS on CPAW operability.

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Hejczyk, Tomasz, Marian Urbańczyk, Tadeusz Pustelny, and Wiesław Jakubik. "Numerical and Experimental Analysis of the Response of a SAW Structure with WO3 Layers on Action of Carbon Monoxide." Archives of Acoustics 40, no. 1 (March 1, 2015): 19–24. http://dx.doi.org/10.1515/aoa-2015-0003.

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Abstract The paper presents the results of an analysis of gaseous sensors based on a surface acoustic wave (SAW) by means of the equivalent model theory. The applied theory analyzes the response of the SAW sensor in the steady state affected by carbon monoxide (CO) in air. A thin layer of WO3 has been used as a sensor layer. The acoustical replacing impedance of the sensor layer was used, which takes into account the profile of the concentration of gas molecules in the layer. Thanks to implementing the Ingebrigtsen equation, the authors determined analytical expressions for the relative changes of the velocity of the surface acoustic wave in the steady state. The results of the analysis have shown that there is an optimum thickness of the layer of CO sensor at which the acoustoelectric effect (manifested here as a change in the acoustic wave velocity) is at its highest. The theoretical results were verified and confirmed experimentally

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Tian, Yahui, Honglang Li, Wencan Chen, Zixiao Lu, Wei Luo, Xihui Mu, and Litian Wang. "A Novel Love Wave Mode Sensor Waveguide Layer with Microphononic Crystals." Applied Sciences 11, no. 17 (September 1, 2021): 8123. http://dx.doi.org/10.3390/app11178123.

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Surface acoustic wave (SAW) sensors have been applied in various areas with many advantages, such as their small size, high sensitivity and wireless and passive form. Love wave mode sensors, an important kind of SAW sensor, are mostly used in biology and chemistry monitoring, as they can be used in a liquid environment. Common Love wave mode sensors consist of a delay line with waveguide and sensitive layers. To extend the application of Love wave mode sensors, this article reports a novel Love wave mode sensor consisting of a waveguide layer with microphononic crystals (PnCs). To analyze the properties of the new structure, the band structure was calculated, and transmission was obtained by introducing delay line structures and quasi-three-dimensional models. Furthermore, devices with a traditional structure and novel structure were fabricated. The results show that, by introducing the designed microstructure of phononic crystals in the waveguide layer, the attenuation was barely increased, and the frequency was shifted by a small amount. In the liquid environmental experiments, the novel structure with micro PnCs shows even better character than the traditional one. Moreover, the introduced microstructure can be extended to microreaction tanks for microcontrol. Therefore, this novel Love wave mode sensor is a promising application for combining acoustic sensors and microfluidics.

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Mandal, Debdyuti, and Sourav Banerjee. "Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications." Sensors 22, no. 3 (January 21, 2022): 820. http://dx.doi.org/10.3390/s22030820.

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Surface acoustic waves (SAWs) are the guided waves that propagate along the top surface of a material with wave vectors orthogonal to the normal direction to the surface. Based on these waves, SAW sensors are conceptualized by employing piezoelectric crystals where the guided elastodynamic waves are generated through an electromechanical coupling. Electromechanical coupling in both active and passive modes is achieved by integrating interdigitated electrode transducers (IDT) with the piezoelectric crystals. Innovative meta-designs of the periodic IDTs define the functionality and application of SAW sensors. This review article presents the physics of guided surface acoustic waves and the piezoelectric materials used for designing SAW sensors. Then, how the piezoelectric materials and cuts could alter the functionality of the sensors is explained. The article summarizes a few key configurations of the electrodes and respective guidelines for generating different guided wave patterns such that new applications can be foreseen. Finally, the article explores the applications of SAW sensors and their progress in the fields of biomedical, microfluidics, chemical, and mechano-biological applications along with their crucial roles and potential plans for improvements in the long-term future in the field of science and technology.

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Hamamed, Najah, Charfeddine Mechri, Taoufik Mhammedi, Nourdin Yaakoubi, Rachid El Guerjouma, Slim Bouaziz, and Mohamed Haddar. "Comparative Study of Leak Detection in PVC Water Pipes Using Ceramic, Polymer, and Surface Acoustic Wave Sensors." Sensors 23, no. 18 (September 7, 2023): 7717. http://dx.doi.org/10.3390/s23187717.

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The detection and location of pipeline leakage can be deduced from the time arrival leak signals measured by acoustic sensors placed at the pipe. Ongoing research in this field is primarily focused on refining techniques for accurately estimating the time delays. This enhancement predominantly revolves around the application of advanced signal processing methods. Additionally, researchers are actively immersed in the utilization of machine learning approaches on vibro-acoustic data files, to determine the presence or absence of leaks. Less attention has been given to evaluating the sensitivity, performance, and overall effectiveness of these sensors in leak detection; although acoustic methods have been successfully used for leak detection in metallic pipes, they are less effective in plastic pipes due to the high attenuation of leak noise signals. The primary thrust of this research centers on identifying sensors that not only possess sensitivity but also exhibit high efficiency. To accomplish this goal, we conducted an exhaustive evaluation of the performance of three distinct categories of acoustic sensors employed for detecting water leaks in plastic pipes: specifically, lead zirconate titanate (PZT) sensors, polyvinylidene fluoride (PVDF) sensors, and surface acoustic wave (SAW) sensors. Our evaluation encompassed the performance of PVDF and SAW sensors in leak detection, comparing them to PZT sensors under a variety of conditions, including different leak sizes, flow rates, and distances from the leak. The results showed that all three sensors, when they were placed in the same position, were able to detect water leaks in plastic pipes with different sensitivities. For small leaks (1 mm, 2 mm), the PVDF sensor showed the greatest sensitivity (0.4 dB/L/h, 0.33 dB/L/h), followed by the SAW sensor (0.16 dB/L/h, 0.14 dB/L/h), and finally the PZT (0.13 dB/L/h, 0.12 dB/L/h). Similarly, for larger leaks (4 mm, 10 mm), the PVDF sensor continued to show superior sensitivity (0.2 dB/L/h, 0.17 dB/L/h), followed by the SAW sensor (0.13 dB/L/h, 0.11), and finally the PZT sensor (0.12 dB/L/h, 0.1 dB/L/h), outperforming the PZT sensor. This suggests that SAW and PVDF sensors, have the potential to serve as valuable, cost-effective alternatives to traditional commercial leak noise transducers. The outcomes of this comparative study involving three acoustic sensors hold the potential to advance the development of robust and dependable systems for the detection of water leaks in plastic pipelines.

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Joseph, Roshan, Hanfei Mei, Asaad Migot, and Victor Giurgiutiu. "Crack-Length Estimation for Structural Health Monitoring Using the High-Frequency Resonances Excited by the Energy Release during Fatigue-Crack Growth." Sensors 21, no. 12 (June 20, 2021): 4221. http://dx.doi.org/10.3390/s21124221.

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Acoustic waves are widely used in structural health monitoring (SHM) for detecting fatigue cracking. The strain energy released when a fatigue crack advances has the effect of exciting acoustic waves, which travel through the structures and are picked up by the sensors. Piezoelectric wafer active sensors (PWAS) can effectively sense acoustic waves due to fatigue-crack growth. Conventional acoustic-wave passive SHM, which relies on counting the number of acoustic events, cannot precisely estimate the crack length. In the present research, a novel method for estimating the crack length was proposed based on the high-frequency resonances excited in the crack by the energy released when a crack advances. In this method, a PWAS sensor was used to sense the acoustic wave signal and predict the length of the crack that generated the acoustic event. First, FEM analysis was undertaken of acoustic waves generated due to a fatigue-crack growth event on an aluminum-2024 plate. The FEM analysis was used to predict the wave propagation pattern and the acoustic signal received by the PWAS mounted at a distance of 25 mm from the crack. The analysis was carried out for crack lengths of 4 and 8 mm. The presence of the crack produced scattering of the waves generated at the crack tip; this phenomenon was observable in the wave propagation pattern and in the acoustic signals recorded at the PWAS. A study of the signal frequency spectrum revealed peaks and valleys in the spectrum that changed in frequency and amplitude as the crack length was changed from 4 to 8 mm. The number of peaks and valleys was observed to increase as the crack length increased. We suggest this peak–valley pattern in the signal frequency spectrum can be used to determine the crack length from the acoustic signal alone. An experimental investigation was performed to record the acoustic signals in crack lengths of 4 and 8 mm, and the results were found to match well with the FEM predictions.

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Kukaev, Alexander, Dmitry Lukyanov, Denis Mikhailenko, Daniil Safronov, Sergey Shevchenko, Vladimir Venediktov, and Andrey Vlasov. "Formation of a Complex Topologies of SAW-Based Inertial Sensors by Laser Thin Film Local Evaporation." Micromachines 12, no. 1 (December 24, 2020): 10. http://dx.doi.org/10.3390/mi12010010.

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Originally, sensors based on surface acoustic waves are fabricated using photolithography, which becomes extremely expensive when a small series or even single elements are needed for the research. A laser thin film local evaporation technique is proposed to substitute the photolithography process in the production of surface acoustic wave based inertial sensors prototypes. To estimate its potential a prototype of a surface acoustic wave gyroscope sensing element was fabricated and tested. Its was shown that the frequency mismatch is no more than 1%, but dispersion of the wave on small inertial masses leads to a spurious parasitic signal on receiving electrodes. Possible ways of its neglecting is discussed.

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Park, Joseph, Robert Heitsenrether, and William Sweet. "Water Level and Wave Height Estimates at NOAA Tide Stations from Acoustic and Microwave Sensors." Journal of Atmospheric and Oceanic Technology 31, no. 10 (October 1, 2014): 2294–308. http://dx.doi.org/10.1175/jtech-d-14-00021.1.

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Abstract The National Oceanic and Atmospheric Administration (NOAA) is transitioning the primary water level sensor at the majority of tide stations in the National Water Level Observation Network (NWLON) from an acoustic ranging system to a microwave radar system. Field comparison of the acoustic and microwave systems finds statistically equivalent performance when temperature gradients between the acoustic sensor and water surface are small and when significant wave height is less than roughly 0.5 m. When significant wave height is greater than approximately 0.5–1 m, the acoustic system consistently reports lower water levels. An analysis of 2 months of acoustic and microwave water level data at Duck, North Carolina, finds that the majority of differences between the two sensors can be attributed to systemic errors in the acoustic system and that the microwave system captures water level variability with higher fidelity than the acoustic system. NWLON real-time data products include the water level standard deviation, a statistic that can serve as a proxy for significant wave height. This study identifies 29 coastal water level stations that are candidates for monitoring wave height based on water level standard deviation, potentially adding a significant source of data for the sparsely sampled coastal wave fields around the United States, and finds that the microwave sensor is better suited than the acoustic system for wave height estimates.

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Sun, Yanming, Zhe Dong, Zhezhe Ding, Neng Wang, Lei Sun, Heming Wei, and Guo Ping Wang. "Carbon Nanocoils and Polyvinyl Alcohol Composite Films for Fiber-Optic Fabry–Perot Acoustic Sensors." Coatings 12, no. 10 (October 21, 2022): 1599. http://dx.doi.org/10.3390/coatings12101599.

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Carbon nanocoils (CNCs) are widely used in functional devices due to their helical morphology, which can be utilized in the fabrication of functional materials with unique properties. In this study, CNCs/polyvinyl alcohol (PVA) composite films were prepared using an electrostatic spinning method and used to form a diaphragm for Fabry–Perot acoustic sensors. With the addition of CNCs, the fabricated composite film showed enhanced mechanical performance responding to acoustic wave pressure. Considering the optical and mechanical response, the content of CNCs was set as 0.14 wt.%; the highest acoustic wave pressure response of the sensor was 1.89 V/Pa at 16.2 kHz, which was relatively higher than that of devices with pure polymer films. Additionally, the sensor had a broadband frequency response from 2 to 10 kHz. The results indicate that the proposed composite film acoustic sensor is suitable for low-frequency acoustic sensing, which lays the foundation for the extended application of functional sensors based on CNCs.

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Viespe, Dinca, Popescu-Pelin, and Miu. "Love Wave Surface Acoustic Wave Sensor with Laser-Deposited Nanoporous Gold Sensitive Layer." Sensors 19, no. 20 (October 16, 2019): 4492. http://dx.doi.org/10.3390/s19204492.

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Laser-deposited gold immobilization layers with different porosities were incorporated into Love Wave Surface Acoustic Wave sensors (LW-SAWs). Acetylcholinesterase (AChE) enzyme was immobilized onto three gold interfaces with different morphologies, and the sensor response to chloroform was measured. The response of the sensors to various chloroform concentrations indicates that their sensing properties (sensitivity, limit of detection) are considerably improved when the gold layers are porous, in comparison to a conventional dense gold layer. The results obtained can be used to improve properties of SAW-based biosensors by controlling the nanostructure of the gold immobilization layer, in combination with other enzymes and proteins, since the design of the present sensor is the same as that for a Love Wave biosensor.

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Mukhin, Nikolay V. "Microfluidic Acoustic Metamaterial SAW Based Sensor." Journal of the Russian Universities. Radioelectronics 22, no. 4 (October 1, 2019): 75–81. http://dx.doi.org/10.32603/1993-8985-2019-22-4-75-81.

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Introduction. Microacoustic sensors based on surface acoustic wave (SAW) devices allow the sensor integration into a wafer based microfluidic analytical platforms such as lab-on-a-chip. Currently exist various approaches of application of SAW devices for liquid properties analysis. But this sensors probe only a thin interfacial liquid layer. The motivation to develop the new SAW-based sensor is to overcome this limitation. The new sensor introduced here uses acoustic measurements, including surface acoustic waves (SAW) and acoustic methamaterial sensor approaches. The new sensor can become the starting point of a new class of microsensor. It measures volumetric properties of liquid analytes in a cavity, not interfacial properties to some artificial sensor surface as the majority of classical chemical and biochemical sensors.Objective. The purpose of the work is to find solutions to overcome SAW-based liquid sensors limitations and the developing of a new sensor that uses acoustic measurements and includes a SAW device and acoustic metamaterial.Materials and methods. A theoretical analysis of sensor structure was carried out on the basis of numerical simulation using COMSOL Multiphysics software. Lithium niobate (LiNbO3) 127.86° Y-cut with wave propagation in the X direction was chosen as a substrate material. Microfluidic structure was designed as a set of rectangular shape channels. A method for measuring volumetric properties of liquids, based on SAW based fluid sensor concept, comprising the steps of: (a) providing sensor structure with the key elements: a SAW resonator, a high-Q set of liquid-filled cavities and intermediate layer with artificial elastic properties between them; (b) measuring of resonance frequency shift, associated with the resonance in liquid-filled cavity, in the response of weakly coupled resonators of SAW resonator loaded by periodic microfluidic structure; (c) determination of volumetric properties of the fluid on the basis of a certain relationship between the speed of sound in liquid, the resonant frequency of the set of liquid-filled cavities, and the geometry design of the cavity.Results. The new sensor approach is introduced. The eigenmodes of the sensor structure with a liquid analyte are carried out. The characteristic of sensor structure is determined. The key elements of introduced microfluidic sensor are a SAW structure, an acoustic metamaterial with a periodic set of microfluidic channels. The SAW device acts as electromechanical transducer. It excites surface waves propagating in the X direction lengthwise the periodic structure and detects the acoustic load generated by the microfluidic structure resonator. The origin of the sensor signal is a small frequency change caused by small variations of acoustic properties of the analyte within the set of microfluidic channels.Conclusion. The principle of the new microacoustic sensor, which can become the basis for creating a new class of microfluidic sensors, is shown.

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Jiang, Jing Bo, Zuo Tao Ni, Si Ren Li, and De Jun Gong. "A Wave-Powered Technique for Water Column Profiling." Applied Mechanics and Materials 284-287 (January 2013): 1739–43. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.1739.

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A technique using surface wave energy to move a sensor platform up and down a mooring wire is introduced in this paper. It permits a complete vertical profile to be obtained with a single sensor, eliminating the need for multiple sensors on the mooring line. The sensor platform can be pre-programmed to dwell at depth for set periods of time. The platform can be configured to carry a variety of payloads including CTD, optical and acoustic sensors.

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Filipiak, Jerzy, Lech Solarz, and Grzegorz Steczko. "Surface Acoustic Wave (SAW) Vibration Sensors." Sensors 11, no. 12 (December 19, 2011): 11809–32. http://dx.doi.org/10.3390/s111211809.

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Hribšek, M. F., S. S. Ristić, and B. M. Radojković. "Diamond in Surface Acoustic Wave Sensors." Acta Physica Polonica A 117, no. 5 (May 2010): 794–98. http://dx.doi.org/10.12693/aphyspola.117.794.

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Jen, Cheng‐Kuei. "Thin rod flexural acoustic wave sensors." Journal of the Acoustical Society of America 98, no. 1 (July 1995): 22. http://dx.doi.org/10.1121/1.413761.

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Fritze, Holger. "High-temperature bulk acoustic wave sensors." Measurement Science and Technology 22, no. 1 (December 1, 2010): 012002. http://dx.doi.org/10.1088/0957-0233/22/1/012002.

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Locke, Stanley, Bikash K. Sinha, and Michael P. Ekstrom. "Rounded wall surface acoustic wave sensors." Journal of the Acoustical Society of America 81, no. 5 (May 1987): 1653–54. http://dx.doi.org/10.1121/1.395104.

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Caliendo, C., M. Hamidullah, I. E. Kuznetsova, V. I. Anisimkin, and E. Verona. "Acoustic Wave Sensors for Liquid Environments." Procedia Technology 27 (2017): 212–13. http://dx.doi.org/10.1016/j.protcy.2017.04.089.

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Vellekoop, Michael J. "Acoustic wave sensors and their technology." Ultrasonics 36, no. 1-5 (February 1998): 7–14. http://dx.doi.org/10.1016/s0041-624x(97)00146-7.

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41

Welsch, W., C. Klein, R. M. Öksüzoglu, M. von Schickfus, and S. Hunklinger. "Immunosensing with surface acoustic wave sensors." Sensors and Actuators A: Physical 62, no. 1-3 (July 1997): 562–64. http://dx.doi.org/10.1016/s0924-4247(97)01569-0.

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42

Jakubik, Wiesław P. "Surface acoustic wave-based gas sensors." Thin Solid Films 520, no. 3 (November 2011): 986–93. http://dx.doi.org/10.1016/j.tsf.2011.04.174.

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43

Kondoh, Jun, and Showko Shiokawa. "Shear—Horizontal Surface Acoustic Wave Sensors." Sensors Update 6, no. 1 (November 1999): 59–78. http://dx.doi.org/10.1002/1616-8984(199911)6:1<59::aid-seup59>3.0.co;2-s.

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Li, Yuanyuan, Wenke Lu, Changchun Zhu, Qinghong Liu, Haoxin Zhang, and Chenchao Tang. "Circuit Design of Surface Acoustic Wave Based Micro Force Sensor." Mathematical Problems in Engineering 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/701723.

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Pressure sensors are commonly used in industrial production and mechanical system. However, resistance strain, piezoresistive sensor, and ceramic capacitive pressure sensors possess limitations, especially in micro force measurement. A surface acoustic wave (SAW) based micro force sensor is designed in this paper, which is based on the theories of wavelet transform, SAW detection, and pierce oscillator circuits. Using lithium niobate as the basal material, a mathematical model is established to analyze the frequency, and a peripheral circuit is designed to measure the micro force. The SAW based micro force sensor is tested to show the reasonable design of detection circuit and the stability of frequency and amplitude.

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Fogel, Ronen, Janice Limson, and Ashwin A. Seshia. "Acoustic biosensors." Essays in Biochemistry 60, no. 1 (June 30, 2016): 101–10. http://dx.doi.org/10.1042/ebc20150011.

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Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors.

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Aktaş, Başak, Talha Şahin, Ersin Toptaş, Aydın Güllü, Ahmet Feyzioğlu, and Sezgin Ersoy. "Material selection in sensor design for additive manufacturing." Journal of Mechatronics and Artificial Intelligence in Engineering 4, no. 2 (December 30, 2023): 122–32. http://dx.doi.org/10.21595/jmai.2023.23794.

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Surface acoustic sensor technology plays a crucial role in numerous mechatronic systems as it enables the detection of physical interactions with the environment. These sensors, operating at micro scales, can be seamlessly integrated into various industrial applications. To harness their full potential, it is essential to establish a systematic approach for the design and manufacturing of these sensors to meet the demands of cutting-edge applications. This study focuses on creating a finite element analysis-based model, aiming to identify the most suitable Interdigital Transducer (IDT) material for the production of surface acoustic wave sensors using additive manufacturing techniques. By leveraging statistical methods, the research seeks to optimize material selection. The structural design parameters of the chosen material will then be utilized to evaluate the performance of the surface acoustic wave sensor. The study also delves into the prospective applications of this technology in diverse fields, shedding light on its promising future.

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He, X. L., J. Zhou, W. B. Wang, W. P. Xuan, D. J. Li, S. R. Dong, H. Jin, Y. Xu, and J. K. Luo. "Flexible Surface Acoustic Wave Based Temperature and Humidity Sensors." MRS Proceedings 1659 (2014): 75–80. http://dx.doi.org/10.1557/opl.2014.111.

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ABSTRACTFlexible surface acoustic wave (SAW) based temperature and humidity sensors were fabricated and characterized. ZnO piezoelectric films were deposited on polyimide substrates by DC magnetron sputtering. ZnO films possess (0002) crystal orientation with large grain sizes of 50∼70 nm. SAW devices showed two wave modes, namely the Rayleigh and Lamb modes, with the frequencies at fR ∼132MHz and fL∼427MHz respectively for a wavelength of 12 μm device. The two resonant frequencies have a temperature coefficient of frequency (TCF) of −423ppm/K and −258ppm/K for the Rayleigh and Lamb waves, respectively. The SAW sensors exhibited a good repeatability in responding to cyclic change of humidity. The responses of the sensors increase with the increase in humidity, and the sensitivity increases with the decrease in wavelength. A high sensitivity of 34.7 kHz/10%RH has been obtained from a SAW device without any surface treatment, demonstrated that the flexible SAW humidity sensors are very promising for application in flexible sensors and microsystems.

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Martin, James S., Andrew Lawrence, and Karim G. Sabra. "Standing wave tube for the calibration of acoustic vector sensors." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A194. http://dx.doi.org/10.1121/10.0016000.

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Acoustic vector sensors are useful in a variety of applications as they provide directional information for ambient noise by sensing the acoustic particle motion in addition to the acoustic pressure. Traditionally, the motion sensor is an accelerometer that is calibrated separately from the associated hydrophone. There are certain advantages that can be realized by calibrating the accelerometer and hydrophone concurrently in a standing wave tube at low frequencies. First, since the pressure and acceleration are simply related in this environment both sensors can be calibrated against a single reference hydrophone. Second, the vector sensor can be calibrated along with the suspension that will be used to mount it thereby taking into account any effects of the suspension’s dynamics. Third, the vector sensor is calibrated to the fluid acceleration rather than its own acceleration thereby accounting for any mismatch in its density relative to the fluid as well as the suspension dynamics. And fourth, the phase response of the acceleration output relative to the pressure output is measured in the calibration. This technique was implemented using a travelling wave tube that was developed for other applications and found to be accurate and convenient.

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Dong, Qi, Qutong Yang, Xiaoyang Liu, Shenghe Hu, Wenzhe Nie, Zhao Jiang, Xiaoming Fan, Jingting Luo, Ran Tao, and Chen Fu. "Ultra-High Frequency Surface Acoustic Wave Sensors for Temperature Detection." Micromachines 15, no. 1 (January 15, 2024): 135. http://dx.doi.org/10.3390/mi15010135.

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Highly sensitive surface acoustic wave (SAW) sensors have recently been recognized as a promising tool for various industrial and medical applications. However, existing SAW sensors generally suffer from a complex design, large size, and poor robustness. In this paper, we develop a simple and stable delay line ultra-high frequency (UHF) SAW sensor for highly sensitive detection of temperature. A Z-shaped delay line is specially designed on the piezoelectric substrate to improve the sensitivity and reduce the substrate size. Herein, the optimum design parameters of extremely short-pitch interdigital transducers (IDTs) are given by numerical simulations. The extremely short pitch gives the SAW sensor ultra-high operating frequency and consequently ultra-high sensitivity. Several experiments are conducted to demonstrate that the sensitivity of the Z-shaped SAW delay line sensor can reach up to 116.685°/°C for temperature detection. The results show that the sensor is an attractive alternative to current SAW sensing platforms in many applications.

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Lutter, Klaus, Alexander Backer, and Klaus Stefan Drese. "Guided Acoustic Waves in Polymer Rods with Varying Immersion Depth in Liquid." Sensors 23, no. 24 (December 18, 2023): 9892. http://dx.doi.org/10.3390/s23249892.

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Monitoring tanks and vessels play an important part in public infrastructure and several industrial processes. The goal of this work is to propose a new kind of guided acoustic wave sensor for measuring immersion depth. Common sensor types such as pressure sensors and airborne ultrasonic sensors are often limited to non-corrosive media, and can fail to distinguish between the media they reflect on or are submerged in. Motivated by this limitation, we developed a guided acoustic wave sensor made from polyethylene using piezoceramics. In contrast to existing sensors, low-frequency Hanning-windowed sine bursts were used to excite the L(0,1) mode within a solid polyethylene rod. The acoustic velocity within these rods changes with the immersion depth in the surrounding fluid. Thus, it is possible to detect changes in the surrounding media by measuring the time shifts of zero crossings through the rod after being reflected on the opposite end. The change in time of zero crossings is monotonically related to the immersion depth. This relative measurement method can be used in different kinds of liquids, including strong acids or bases.

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Journal articles on the topic 'Acoustic Wave Sensors'

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