A miniaturized acoustic vector sensor with PIN-PMN-PT single crystal cantilever beam accelerometers

Directional sound detection using vector sensors rather than large hydrophone arrays is highly advantageous for target detection in SONAR. However, developing highly sensitive and compact vector sensors for use in a system whose size is limited has been a challenging issue. In this paper, we describe a miniaturized acoustic vector sensor with piezoelectric single crystal accelerometers for the application in towed line arrays. A mass-loaded cantilever beam accelerometer with a [011] poled PIN-PMN-PT single crystal shows a better signal-to-noise ratio compared to accelerometers with other piezoelectric materials because of its superior piezoelectric properties in the 32 direction. We suggested a sufficiently compact vector sensor by using a cylindrical hydrophone with 10 mm in diameter as a housing of the single crystal accelerometers. Two single crystal accelerometers were orthogonally mounted inside the cylindrical hydrophone to detect direction of sound in the transverse plane of the line array. The receiving voltage sensitivity of the accelerometers and hydrophone was −199 and −196 dB, respectively, at 3 kHz. The directional cardioid beams generated by summing the omnidirectional beam from the hydrophone and the dipole beam from the accelerometers were validated over the entire operating frequency.

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The Design and Optimization of a Compressive-Type Vector Sensor Utilizing a PMN-28PT Piezoelectric Single-Crystal

Sensors ◽

10.3390/s19235155 ◽

2019 ◽

Vol 19 (23) ◽

pp. 5155

Author(s):

Hong Goo Yeo ◽

Junhee Choi ◽

Changzhu Jin ◽

Seonghun Pyo ◽

Yongrae Roh ◽

...

Keyword(s):

Single Crystal ◽

Single Crystals ◽

Axial Vector ◽

Geometric Optimization ◽

Voltage Sensitivity ◽

Element Analysis ◽

Design And Optimization ◽

Seismic Mass ◽

Vector Sensor ◽

Dipole Pattern

Underwater sensors that detect the distance and direction of acoustic sources are critical for surveillance monitoring and target detection in the water. Here, we propose an axial vector sensor that utilizes a small (~1 cm3) compressive-type piezoelectric accelerometer using piezoelectric single crystals. Initially, finite element analysis (FEA) was used to optimize the structure that comprised piezoelectric Pb(Mb1/3Nb2/3)O3-28%PbTiO3 single crystals on a tungsten seismic mass. The receiving voltage sensitivity (RVS) was enhanced through geometric optimization of the thickness and sensing area of the piezoelectric material and the seismic mass. The estimated maximum RVS of the optimized vector sensor was −212 dB. FEA simulations and practical measurements were used to verify the directivity of the vector sensor design, which exhibited a dipole pattern. The dipole beam pattern was used to obtain cardioid patterns using the simulated and measured results for comparison. The results clearly showed the feasibility of using the proposed piezoelectric single-crystal accelerometer for a compressive-type vector sensor.

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An Improved Generalized Inverse Beamforming-Noise Source Localization Method Using Acoustic Vector Sensor Arrays

IEEE Sensors Journal ◽

10.1109/jsen.2021.3076187 ◽

2021 ◽

pp. 1-1

Author(s):

Shengguo Shi ◽

Yuan Gao ◽

Desen Yang ◽

Jie Shia ◽

Deyan Tian

Keyword(s):

Source Localization ◽

Generalized Inverse ◽

Noise Source ◽

Sensor Arrays ◽

Acoustic Vector Sensor ◽

Localization Method ◽

Vector Sensor

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Interphotoreceptor coupling: an evolutionary perspective

Pflügers Archiv - European Journal of Physiology ◽

10.1007/s00424-021-02572-9 ◽

2021 ◽

Author(s):

Lorenzo Cangiano ◽

Sabrina Asteriti

Keyword(s):

Visual Information ◽

Signal To Noise Ratio ◽

Electrical Coupling ◽

Physiological Role ◽

Cellular Processes ◽

Contact Points ◽

Highly Sensitive ◽

The Many ◽

The Impact

AbstractIn the vertebrate retina, signals generated by cones of different spectral preference and by highly sensitive rod photoreceptors interact at various levels to extract salient visual information. The first opportunity for such interaction is offered by electrical coupling of the photoreceptors themselves, which is mediated by gap junctions located at the contact points of specialised cellular processes: synaptic terminals, telodendria and radial fins. Here, we examine the evolutionary pressures for and against interphotoreceptor coupling, which are likely to have shaped how coupling is deployed in different species. The impact of coupling on signal to noise ratio, spatial acuity, contrast sensitivity, absolute and increment threshold, retinal signal flow and colour discrimination is discussed while emphasising available data from a variety of vertebrate models spanning from lampreys to primates. We highlight the many gaps in our knowledge, persisting discrepancies in the literature, as well as some major unanswered questions on the actual extent and physiological role of cone-cone, rod-cone and rod-rod communication. Lastly, we point toward limited but intriguing evidence suggestive of the ancestral form of coupling among ciliary photoreceptors.

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Influences of soft prolate spheroid baffle on directivity of acoustic vector sensor

The 2010 IEEE International Conference on Information and Automation ◽

10.1109/icinfa.2010.5512415 ◽

2010 ◽

Cited By ~ 1

Author(s):

Jianfei Ji ◽

Guolong Liang ◽

Kai Liu ◽

Yang Li

Keyword(s):

Prolate Spheroid ◽

Acoustic Vector Sensor ◽

Vector Sensor

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Parametrically Excited Electrostatic MEMS Cantilever Beam With Flexible Support

Journal of Vibration and Acoustics ◽

10.1115/1.4034954 ◽

2016 ◽

Vol 139 (2) ◽

Cited By ~ 9

Author(s):

Mark Pallay ◽

Shahrzad Towfighian

Keyword(s):

Cantilever Beam ◽

Large Amplitude ◽

Chaotic Behavior ◽

Signal To Noise Ratio ◽

Mass Sensors ◽

Flexible Support ◽

Sensing Applications ◽

Electrostatic Mems ◽

Fringe Fields ◽

Steady State Amplitude

Parametric resonators that show large amplitude of vibration are highly desired for sensing applications. In this paper, a microelectromechanical system (MEMS) parametric resonator with a flexible support that uses electrostatic fringe fields to achieve resonance is introduced. The resonator shows a 50% increase in amplitude and a 50% decrease in threshold voltage compared with a fixed support cantilever model. The use of electrostatic fringe fields eliminates the risk of pull-in and allows for high amplitudes of vibration. We studied the effect of decreasing boundary stiffness on steady-state amplitude and found that below a threshold chaotic behavior can occur, which was verified by the information dimension of 0.59 and Poincaré maps. Hence, to achieve a large amplitude parametric resonator, the boundary stiffness should be decreased but should not go below a threshold when the chaotic response will appear. The resonator described in this paper uses a crab-leg spring attached to a cantilever beam to allow for both translation and rotation at the support. The presented study is useful in the design of mass sensors using parametric resonance (PR) to achieve large amplitude and signal-to-noise ratio.

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Two-dimensional DOA estimation of coherent signals using acoustic vector sensor array

Signal Processing ◽

10.1016/j.sigpro.2011.05.021 ◽

2012 ◽

Vol 92 (1) ◽

pp. 19-28 ◽

Cited By ~ 27

Author(s):

P. Palanisamy ◽

N. Kalyanasundaram ◽

P.M. Swetha

Keyword(s):

Sensor Array ◽

Doa Estimation ◽

Two Dimensional ◽

Coherent Signals ◽

Acoustic Vector Sensor ◽

Vector Sensor ◽

Vector Sensor Array

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The Characteristic of the La3Ga5SiO14 Single Crystal Grown by Vertical Bridgman Method in Ar Atmosphere

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.842 ◽

2006 ◽

Vol 510-511 ◽

pp. 842-845 ◽

Cited By ~ 5

Author(s):

Noriko Bamba ◽

Kentaro Kato ◽

Toshinori Taishi ◽

Takayuki Hayashi ◽

Keigo Hoshikawa ◽

...

Keyword(s):

Melting Point ◽

Single Crystal ◽

Single Crystals ◽

Room Temperature ◽

Color Change ◽

Piezoelectric Materials ◽

Lead Free ◽

Piezoelectric Constant ◽

Interstitial Oxygen ◽

Vertical Bridgman

Langasite (La3Ga5SiO14: denoted by LGS) single crystal is one of the lead free piezoelectric materials with high piezoelectricity that is maintained up to its melting point (1470°C). Although LGS single crystals have usually been grown by Czochralski (CZ) method in oxygen contained atmosphere to prevent evaporation of Ga, they were grown by the vertical Bridgman (VB) method in Ar atmosphere without oxygen, and their properties were evaluated in this work. Transparent and colorless LGS single crystals were successfully obtained without Ga evaporation by the VB method in Ar atmosphere, and their resistivity at room temperature was much higher than that grown by conventional CZ method. Piezoelectric constant d11 of the crystal grown by the VB method was 6 x 10-12 C/N, which was close to that of the crystal grown by CZ method. The colorless transparent LGS single crystal turned to orange and its resistivity decreased by annealing in air. Since an orange-colored transparent LGS single crystal has been grown by conventional CZ method, this indicates that color change and the resistivity decrease of LGS crystal is caused by extra interstitial oxygen atoms in the crystal.

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