Piezoelectric MEMS

A special issue of Micromachines (ISSN 2072-666X).

Deadline for manuscript submissions: closed (30 June 2017) | Viewed by 78722

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Special Issue Editors


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Guest Editor
Institute of Sensor and Actuator Systems, TU Wien, 1040 Vienna, Austria
Interests: MEMS (e.g. sensors, actuators); PiezoMEMS; SiCMEMS; MEMS materials (e.g. SiC, AlN, ScAlN, PVDF); material characterization; micro-and nanomachining technologies; NEMS (e.g. sensors, actuators); packaging aspects

E-Mail Website
Guest Editor
Institute of Sensor and Actuator Systems, TU Wien, Vienna 1040, Austria
Interests: AlN, ScAlN, PVDF, SiC, PiezoMEMS; energy harvesting; MEMS resonators

Special Issue Information

Dear Colleagues,

Electromechanical transducers based on piezoelectric layers and thin films are continuously finding their way into micro-electromechanical systems (MEMS). Piezoelectric transducers feature a linear voltage response, no snap-in behavior and can provide both attractive and repulsive forces. This removes inherent physical limitations present in the commonly used electrostatic transducer approach while maintaining beneficial properties such as low-power operation. In order to exploit the full potential of piezoelectric MEMS, interdisciplinary research efforts range from investigations of advanced piezoelectric materials over the design of novel piezoelectric MEMS sensor and actuator devices, to the integration of PiezoMEMS devices into full low-power systems.

In this Special Issue, the current state of this exciting research field will be presented, covering a wide range of topics including, but not limited to:

  • Experimental and theoretical research on piezoelectric materials such as AlN, ScAlN, ZnO or PZT, PVDF with a strong focus on the application in MEMS devices.

  • Deposition and synthesis techniques for piezoelectric materials enabling integration of those materials into MEMS fabrication processes.

  • Modelling and simulation of piezoelectric MEMS devices and systems.

  • Piezoelectric MEMS resonators for measuring physical quantities such as mass, acceleration, yaw rate, pressure and viscosity or density of liquids.

  • Optical MEMS devices, such as scanning micro mirror devices and optical switches, based on piezoelectric MEMS.

  • Acoustic devices, such as SAW, BAW or FBARs and acoustic transducers, based on piezoelectric MEMS such as microphones or loudspeakers.

  • Piezoelectric energy harvesting devices.

  • Specific packaging aspects of piezoelectric devices and systems.

  • Low and zero power systems, featuring low-power sensors combined with energy harvesting devices, at least one of which is based on piezoelectric MEMS.

Prof. Dr. Ulrich Schmid
Dr. Michael Schneider
Guest Editors

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Keywords

  • Piezoelectric materials

  • Simulation and modeling of piezoelectric MEMS

  • Piezoelectric MEMS resonators

  • Acoustic MEMS devices

  • Surface acoustic wave devices

  • Piezoelectric energy harvesting

  • Packaging of piezoelectric MEMS

  • Smart electronics for piezoelectric devices and systems

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Published Papers (14 papers)

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Editorial

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3 pages, 183 KiB  
Editorial
Editorial for the Special Issue on Piezoelectric MEMS
by Ulrich Schmid and Michael Schneider
Micromachines 2018, 9(5), 237; https://doi.org/10.3390/mi9050237 - 15 May 2018
Cited by 2 | Viewed by 2757
Abstract
Electromechanical transducers that utilize the piezoelectric effect have been increasingly used in micro-electromechanical systems (MEMS) either as substrates or as thin films[...] Full article
(This article belongs to the Special Issue Piezoelectric MEMS)

Research

Jump to: Editorial

8 pages, 1701 KiB  
Article
Design and Simulation of A Novel Piezoelectric AlN-Si Cantilever Gyroscope
by Jian Yang, Chaowei Si, Fan Yang, Guowei Han, Jin Ning, Fuhua Yang and Xiaodong Wang
Micromachines 2018, 9(2), 81; https://doi.org/10.3390/mi9020081 - 15 Feb 2018
Cited by 9 | Viewed by 4589
Abstract
A novel design of piezoelectric aluminum nitride (AlN)-Si composite cantilever gyroscope is proposed in this paper. The cantilever is stimulated to oscillate in plane by two inverse voltages which are applied on the two paralleled drive electrodes, respectively. The whole working principles are [...] Read more.
A novel design of piezoelectric aluminum nitride (AlN)-Si composite cantilever gyroscope is proposed in this paper. The cantilever is stimulated to oscillate in plane by two inverse voltages which are applied on the two paralleled drive electrodes, respectively. The whole working principles are deduced, which based on the piezoelectric equation and elastic vibration equation. In this work, a cantilever gyroscope has been simulated and optimized by COMSOL Multiphysics 5.2a. The drive mode frequency is 87.422 kHz, and the sense mode frequency is 87.414 kHz. The theoretical sensitivity of this gyroscope is 0.145 pm/◦/s. This gyroscope has a small size and simple structure. It will be a better choice for the consumer electronics. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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22 pages, 5163 KiB  
Article
Compensation of Hysteresis on Piezoelectric Actuators Based on Tripartite PI Model
by Dong An, Haodong Li, Ying Xu and Lixiu Zhang
Micromachines 2018, 9(2), 44; https://doi.org/10.3390/mi9020044 - 26 Jan 2018
Cited by 19 | Viewed by 5730
Abstract
Piezoelectric ceramic actuators have been widely used in nanopositioning applications owing to their fast response, high stiffness, and ability to generate large forces. However, the existence of nonlinearities such as hysteresis can greatly deteriorate the accuracy of the manipulation, even causing instability of [...] Read more.
Piezoelectric ceramic actuators have been widely used in nanopositioning applications owing to their fast response, high stiffness, and ability to generate large forces. However, the existence of nonlinearities such as hysteresis can greatly deteriorate the accuracy of the manipulation, even causing instability of the whole system. In this article, we have explained the causes of hysteresis based on the micropolarization theory and proposed a piezoelectric ceramic deformation speed law. For this, we analyzed the piezoelectric ceramic actuator deformation speed law based on the domain wall theory. Based on this analysis, a three-stage Prandtl–Ishlinskii (PI) model (hereafter referred to as tripartite PI model) was designed and implemented. According to the piezoelectric ceramic deformation speed law, this model makes separate local PI models in different parts of piezoelectric ceramics’ hysteresis curve. The weighting values and threshold values of the tripartite PI model were obtained through a quadratic programming optimization algorithm. Compared to the classical PI model, the tripartite PI model can describe the asymmetry of hysteresis curves more accurately. A tripartite PI inverse controller, PI inverse controller, and Preisach inverse controller were used to compensate for the piezoelectric ceramic actuator in the experiment. The experimental results show that the inclusion of the PI inverse controller and the Preisach inverse controller improved the tracking performance of the tripartite PI inverse model by more than 80%. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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2126 KiB  
Article
Transparent Ferroelectric Capacitors on Glass
by Daniele Sette, Stéphanie Girod, Renaud Leturcq, Sebastjan Glinsek and Emmanuel Defay
Micromachines 2017, 8(10), 313; https://doi.org/10.3390/mi8100313 - 20 Oct 2017
Cited by 11 | Viewed by 4767
Abstract
We deposited transparent ferroelectric lead zirconate titanate thin films on fused silica and contacted them via Al-doped zinc oxide (AZO) transparent electrodes with an interdigitated electrode (IDE) design. These layers, together with a TiO2 buffer layer on the fused silica substrate, are [...] Read more.
We deposited transparent ferroelectric lead zirconate titanate thin films on fused silica and contacted them via Al-doped zinc oxide (AZO) transparent electrodes with an interdigitated electrode (IDE) design. These layers, together with a TiO2 buffer layer on the fused silica substrate, are highly transparent (>60% in the visible optical range). Fully crystallized Pb(Zr0.52Ti0.48)O3 (PZT) films are dielectrically functional and exhibit a typical ferroelectric polarization loop with a remanent polarization of 15 μC/cm2. The permittivity value of 650, obtained with IDE AZO electrodes is equivalent to the one measured with Pt electrodes patterned with the same design, which proves the high quality of the developed transparent structures. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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8400 KiB  
Article
Spiral-Shaped Piezoelectric MEMS Cantilever Array for Fully Implantable Hearing Systems
by Péter Udvardi, János Radó, András Straszner, János Ferencz, Zoltán Hajnal, Saeedeh Soleimani, Michael Schneider, Ulrich Schmid, Péter Révész and János Volk
Micromachines 2017, 8(10), 311; https://doi.org/10.3390/mi8100311 - 18 Oct 2017
Cited by 28 | Viewed by 7542
Abstract
Fully implantable, self-powered hearing aids with no external unit could significantly increase the life quality of patients suffering severe hearing loss. This highly demanding concept, however, requires a strongly miniaturized device which is fully implantable in the middle/inner ear and includes the following [...] Read more.
Fully implantable, self-powered hearing aids with no external unit could significantly increase the life quality of patients suffering severe hearing loss. This highly demanding concept, however, requires a strongly miniaturized device which is fully implantable in the middle/inner ear and includes the following components: frequency selective microphone or accelerometer, energy harvesting device, speech processor, and cochlear multielectrode. Here we demonstrate a low volume, piezoelectric micro-electromechanical system (MEMS) cantilever array which is sensitive, even in the lower part of the voice frequency range (300–700 Hz). The test array consisting of 16 cantilevers has been fabricated by standard bulk micromachining using a Si-on-Insulator (SOI) wafer and aluminum nitride (AlN) as a complementary metal-oxide-semiconductor (CMOS) and biocompatible piezoelectric material. The low frequency and low device footprint are ensured by Archimedean spiral geometry and Si seismic mass. Experimentally detected resonance frequencies were validated by an analytical model. The generated open circuit voltage (3–10 mV) is sufficient for the direct analog conversion of the signals for cochlear multielectrode implants. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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5523 KiB  
Article
Design, Characterization and Sensitivity Analysis of a Piezoelectric Ceramic/Metal Composite Transducer
by Muhammad Bin Mansoor, Sören Köble, Tin Wang Wong, Peter Woias and Frank Goldschmidtböing
Micromachines 2017, 8(9), 271; https://doi.org/10.3390/mi8090271 - 5 Sep 2017
Cited by 13 | Viewed by 5448
Abstract
This article presents experimental characterization and numerical simulation techniques used to create large amplitude and high frequency surface waves with the help of a metal/ceramic composite transducer array. Four piezoelectric bimorph transducers are cascaded and operated in a nonlinear regime, creating broad band [...] Read more.
This article presents experimental characterization and numerical simulation techniques used to create large amplitude and high frequency surface waves with the help of a metal/ceramic composite transducer array. Four piezoelectric bimorph transducers are cascaded and operated in a nonlinear regime, creating broad band resonant vibrations. The used metallic plate itself resembles a movable wall which can align perfectly with an airfoil surface. A phase-shifted operation of the actuators results in local displacements that generate a surface wave in the boundary layer for an active turbulence control application. The primary focus of this article is actuator design and a systematic parameter variation experiment which helped optimize its nonlinear dynamics. Finite Element Model (FEM) simulations were performed for different design variants, with a primary focus in particular on the minimization of bending stress seen directly on the piezo elements while achieving the highest possible deflection of the vibrating metallic plate. Large output force and a small yield stress (leading to a relatively small output stoke) are characteristics intrinsic to the stiff piezo-ceramics. Optimized piezo thickness and its spatial distribution on the bending surface resulted in an efficient stress management within the bimorph design. Thus, our proposed resonant transduction array achieved surface vibrations with a maximum peak-to-peak amplitude of 500 μ m in a frequency range around 1200 Hz. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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5310 KiB  
Article
Development of Piezo-Driven Compliant Bridge Mechanisms: General Analytical Equations and Optimization of Displacement Amplification
by Huaxian Wei, Bijan Shirinzadeh, Wei Li, Leon Clark, Joshua Pinskier and Yuqiao Wang
Micromachines 2017, 8(8), 238; https://doi.org/10.3390/mi8080238 - 3 Aug 2017
Cited by 49 | Viewed by 6211
Abstract
Compliant bridge mechanisms are frequently utilized to scale micrometer order motions of piezoelectric actuators to levels suitable for desired applications. Analytical equations have previously been specifically developed for two configurations of bridge mechanisms: parallel and rhombic type. Based on elastic beam theory, a [...] Read more.
Compliant bridge mechanisms are frequently utilized to scale micrometer order motions of piezoelectric actuators to levels suitable for desired applications. Analytical equations have previously been specifically developed for two configurations of bridge mechanisms: parallel and rhombic type. Based on elastic beam theory, a kinematic analysis of compliant bridge mechanisms in general configurations is presented. General equations of input displacement, output displacement, displacement amplification, input stiffness, output stiffness and stress are presented. Using the established equations, a piezo-driven compliant bridge mechanism has been optimized to maximize displacement amplification. The presented equations were verified using both computational finite element analysis and through experimentation. Finally, comparison with previous studies further validates the versatility and accuracy of the proposed models. The formulations of the new analytical method are simplified and efficient, which help to achieve sufficient estimation and optimization of compliant bridge mechanisms for nano-positioning systems. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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4090 KiB  
Article
Influences of Excitation on Dynamic Characteristics of Piezoelectric Micro-Jets
by Kai Li, Jun-Kao Liu, Wei-Shan Chen and Lu Zhang
Micromachines 2017, 8(7), 213; https://doi.org/10.3390/mi8070213 - 5 Jul 2017
Cited by 8 | Viewed by 4426
Abstract
Piezoelectric micro-jets are based on piezoelectric ink-jet technology and can achieve the drop-on demand requirements. A piezoelectric micro-jet which is designed for bearing lubrication is presented in this paper. In order to analyze the fluid dynamic characteristics of the piezoelectric micro-jet so as [...] Read more.
Piezoelectric micro-jets are based on piezoelectric ink-jet technology and can achieve the drop-on demand requirements. A piezoelectric micro-jet which is designed for bearing lubrication is presented in this paper. In order to analyze the fluid dynamic characteristics of the piezoelectric micro-jet so as to obtain good injection performance, a direct coupling simulation method is proposed in this paper. The effects of inlet and viscous losses in the cavity are taken into account, which are close to the actual conditions in the direct coupling method. The effects of the pulse excitation parameters on the pinch-off time, tail length, velocity, and volume of the droplet are analyzed by the proposed direct coupling method. The pressure distribution inside the cavity of the micro-jet and the status of the droplet formation at different times are also given. In addition, the method is proved to be effective in predicting and analyzing the fluid dynamic characteristics of piezoelectric micro-jets by comparing the simulation results with the experimental results. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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3724 KiB  
Article
Potential of Piezoelectric MEMS Resonators for Grape Must Fermentation Monitoring
by Georg Pfusterschmied, Javier Toledo, Martin Kucera, Wolfgang Steindl, Stefan Zemann, Víctor Ruiz-Díez, Michael Schneider, Achim Bittner, Jose Luis Sanchez-Rojas and Ulrich Schmid
Micromachines 2017, 8(7), 200; https://doi.org/10.3390/mi8070200 - 26 Jun 2017
Cited by 20 | Viewed by 5927
Abstract
In this study grape must fermentation is monitored using a self-actuating/self-sensing piezoelectric micro-electromechanical system (MEMS) resonator. The sensor element is excited in an advanced roof tile-shaped vibration mode, which ensures high Q-factors in liquids (i.e., Q ~100 in isopropanol), precise resonance frequency [...] Read more.
In this study grape must fermentation is monitored using a self-actuating/self-sensing piezoelectric micro-electromechanical system (MEMS) resonator. The sensor element is excited in an advanced roof tile-shaped vibration mode, which ensures high Q-factors in liquids (i.e., Q ~100 in isopropanol), precise resonance frequency analysis, and a fast measurement procedure. Two sets of artificial model solutions are prepared, representing an ordinary and a stuck/sluggish wine fermentation process. The precision and reusability of the sensor are shown using repetitive measurements (10 times), resulting in standard deviations of the measured resonance frequencies of ~0.1%, Q-factor of ~11%, and an electrical conductance peak height of ~12%, respectively. With the applied evaluation procedure, moderate standard deviations of ~1.1% with respect to density values are achieved. Based on these results, the presented sensor concept is capable to distinguish between ordinary and stuck wine fermentation, where the evolution of the wine density associated with the decrease in sugar and the increase in ethanol concentrations during fermentation processes causes a steady increase in the resonance frequency for an ordinary fermentation. Finally, the first test measurements in real grape must are presented, showing a similar trend in the resonance frequency compared to the results of an artificial solutions, thus proving that the presented sensor concept is a reliable and reusable platform for grape must fermentation monitoring. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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6066 KiB  
Article
Parametric Analysis and Experimental Verification of a Hybrid Vibration Energy Harvester Combining Piezoelectric and Electromagnetic Mechanisms
by Zhenlong Xu, Xiaobiao Shan, Hong Yang, Wen Wang and Tao Xie
Micromachines 2017, 8(6), 189; https://doi.org/10.3390/mi8060189 - 18 Jun 2017
Cited by 37 | Viewed by 5793
Abstract
Considering coil inductance and the spatial distribution of the magnetic field, this paper developed an approximate distributed-parameter model of a hybrid energy harvester (HEH). The analytical solutions were compared with numerical solutions. The effects of load resistances, electromechanical coupling factors, mechanical damping ratio, [...] Read more.
Considering coil inductance and the spatial distribution of the magnetic field, this paper developed an approximate distributed-parameter model of a hybrid energy harvester (HEH). The analytical solutions were compared with numerical solutions. The effects of load resistances, electromechanical coupling factors, mechanical damping ratio, coil parameters and size scale on performance were investigated. A meso-scale HEH prototype was fabricated, tested and compared with a stand-alone piezoelectric energy harvester (PEH) and a stand-alone electromagnetic energy harvester (EMEH). The peak output power is 2.93% and 142.18% higher than that of the stand-alone PEH and EMEH, respectively. Moreover, its bandwidth is 108%- and 122.7%-times that of the stand-alone PEH and EMEH, respectively. The experimental results agreed well with the theoretical values. It is indicated that the linearized electromagnetic coupling coefficient is more suitable for low-level excitation acceleration. Hybrid energy harvesting contributes to widening the frequency bandwidth and improving energy conversion efficiency. However, only when the piezoelectric coupling effect is weak or medium can the HEH generate more power than the single-mechanism energy harvester. Hybrid energy harvesting can improve output power even at the microelectromechanical systems (MEMS) scale. This study presents a more effective model for the performance evaluation and structure optimization of the HEH. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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2040 KiB  
Article
Modeling and Identification of the Rate-Dependent Hysteresis of Piezoelectric Actuator Using a Modified Prandtl-Ishlinskii Model
by Yanding Qin, Xin Zhao and Lu Zhou
Micromachines 2017, 8(4), 114; https://doi.org/10.3390/mi8040114 - 4 Apr 2017
Cited by 58 | Viewed by 5620
Abstract
Piezoelectric actuator (PEA) is an ideal microscale and nanoscale actuator because of its ultra-precision positioning resolution. However, the inherent hysteretic nonlinearity significantly degrades the PEA’s accuracy. The measured hysteresis of PEA exhibits strong rate-dependence and saturation phenomena, increasing the difficulty in the hysteresis [...] Read more.
Piezoelectric actuator (PEA) is an ideal microscale and nanoscale actuator because of its ultra-precision positioning resolution. However, the inherent hysteretic nonlinearity significantly degrades the PEA’s accuracy. The measured hysteresis of PEA exhibits strong rate-dependence and saturation phenomena, increasing the difficulty in the hysteresis modeling and identification. In this paper, a modified Prandtl-Ishlinskii (PI) hysteresis model is proposed. The weights of the backlash operators are updated according to the input rates so as to account for the rate-dependence property. Subsequently, the saturation property is realized by cascading a polynomial operator with only odd powers. In order to improve the efficiency of the parameter identification, a special control input consisting of a superimposition of multiple sinusoidal signals is utilized. Because the input rate of such a control input covers a wide range, all the parameters of the hysteresis model can be identified through only one set of experimental data, and no additional curve-fitting is required. The effectiveness of the hysteresis modeling and identification methodology is verified on a PEA-driven flexure mechanism. Experimental results show that the modeling accuracy is on the same order of the noise level of the overall system. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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3522 KiB  
Article
A PZT Actuated Triple-Finger Gripper for Multi-Target Micromanipulation
by Tao Chen, Yaqiong Wang, Zhan Yang, Huicong Liu, Jinyong Liu and Lining Sun
Micromachines 2017, 8(2), 33; https://doi.org/10.3390/mi8020033 - 24 Jan 2017
Cited by 33 | Viewed by 5899
Abstract
This paper presents a triple-finger gripper driven by a piezoceramic (PZT) transducer for multi-target micromanipulation. The gripper consists of three fingers assembled on adjustable pedestals with flexible hinges for a large adjustable range. Each finger has a PZT actuator, an amplifying structure, and [...] Read more.
This paper presents a triple-finger gripper driven by a piezoceramic (PZT) transducer for multi-target micromanipulation. The gripper consists of three fingers assembled on adjustable pedestals with flexible hinges for a large adjustable range. Each finger has a PZT actuator, an amplifying structure, and a changeable end effector. The moving trajectories of single and double fingers were calculated and finite element analyses were performed to verify the reliability of the structures. In the gripping experiment, various end effectors of the fingers such as tungsten probes and fibers were tested, and different micro-objects such as glass hollow spheres and iron spheres with diameters ranging from 10 to 800 μm were picked and released. The output resolution is 145 nm/V, and the driven displacement range of the gripper is 43.4 μm. The PZT actuated triple-finger gripper has superior adaptability, high efficiency, and a low cost. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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5443 KiB  
Article
Comparative Influences of Fluid and Shell on Modeled Ejection Performance of a Piezoelectric Micro-Jet
by Kai Li, Jun-kao Liu, Wei-shan Chen and Lu Zhang
Micromachines 2017, 8(1), 21; https://doi.org/10.3390/mi8010021 - 13 Jan 2017
Cited by 4 | Viewed by 4940
Abstract
The piezoelectric micro-jet, which can achieve the drop-on-demand requirement, is based on ink-jet technology and small droplets can be ejected out by precise control. The droplets are driven out of the nozzle by the acoustic pressure waves which are generated by the piezoelectric [...] Read more.
The piezoelectric micro-jet, which can achieve the drop-on-demand requirement, is based on ink-jet technology and small droplets can be ejected out by precise control. The droplets are driven out of the nozzle by the acoustic pressure waves which are generated by the piezoelectric vibrator. The propagation processes of the acoustic pressure waves are affected by the acoustic properties of the fluid and the shell material of the micro-jet, as well as the excitations and the structure sizes. The influences of the fluid density and acoustic velocity in the fluid on the nozzle pressure and support reaction force of the vibrator are analyzed in this paper. The effects of the shell material on the ejection performance are studied as well. In order to improve the ejection performance of the micro-jet, for ejecting a given fluid, the recommended methods of selecting the shell material and adjusting excitations are provided based on the results, and the influences of the factors on working frequencies are obtained as well. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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5536 KiB  
Article
MEMS Gyroscopes Based on Acoustic Sagnac Effect
by Yuanyuan Yu, Hao Luo, Buyun Chen, Jin Tao, Zhihong Feng, Hao Zhang, Wenlan Guo and Daihua Zhang
Micromachines 2017, 8(1), 2; https://doi.org/10.3390/mi8010002 - 24 Dec 2016
Cited by 7 | Viewed by 7168
Abstract
This paper reports on the design, fabrication and preliminary test results of a novel microelectromechanical systems (MEMS) device—the acoustic gyroscope. The unique operating mechanism is based on the “acoustic version” of the Sagnac effect in fiber-optic gyros. The device measures the phase difference [...] Read more.
This paper reports on the design, fabrication and preliminary test results of a novel microelectromechanical systems (MEMS) device—the acoustic gyroscope. The unique operating mechanism is based on the “acoustic version” of the Sagnac effect in fiber-optic gyros. The device measures the phase difference between two sound waves traveling in opposite directions, and correlates the signal to the angular velocity of the hosting frame. As sound travels significantly slower than light and develops a larger phase change within the same path length, the acoustic gyro can potentially outperform fiber-optic gyros in sensitivity and form factor. It also promises superior stability compared to vibratory MEMS gyros as the design contains no moving parts and is largely insensitive to mechanical stress or temperature. We have carried out systematic simulations and experiments, and developed a series of processes and design rules to implement the device. Full article
(This article belongs to the Special Issue Piezoelectric MEMS)
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