Design of Cellular Piezoelectric Actuators With High Blocking Force and High Strain

2008 ◽  
Author(s):  
Devin Neal ◽  
H. Harry Asada
Keyword(s):  
Lead Zirconate Titanate ◽  
Kinematic Analysis ◽  
High Strain ◽  
Piezoelectric Actuators ◽  
Lead Zirconate ◽  
Preliminary Design ◽  
Practical Applications ◽  
Small Strains ◽  
High Bandwidth ◽  
Subsequent Layer

Preliminary design and analysis of a new concept for efficiently amplifying piezoelectric actuators are presented in this paper. Piezoelectric actuators, such as Lead Zirconate Titanate (PZT), have produced substantial stress at high bandwidth, but at very small strains on the order of 0.1%. This paper presents a new strain amplification design to be utilized as the first layer in the previously designed “nested rhombus” multi-layer mechanism. This mechanism produces substantial strain through exponentially increasing strain with each subsequent layer. However, the blocking force produced in previous designs is insufficient for many practical applications. Through static and kinematic analysis, this paper addresses how this new concept sufficiently amplifies strain, and presents numerous issues to consider in designing for greater blocking force. A prototype of this new concept provides 126 N of blocking force and displacement of 0.3 mm.

scholarly journals New “HAPA”, “FTA”, and “HD-FTA” Piezoelectric Actuators

Proceedings ◽  
2020 ◽  
Vol 64 (1) ◽  
pp. 34
Author(s):  
Dian-Hua Lin ◽  
Yuexue Xia ◽  
Jia-Hao Koh ◽  
Fang-Chih Lim ◽  
Leong-Chew Lim
Keyword(s):  
Lead Zirconate Titanate ◽  
High Performance ◽  
Piezoelectric Actuators ◽  
Vertical Displacement ◽  
Lead Zirconate ◽  
Frame Structure ◽  
Actual Design ◽  
Fractional Increase ◽  
Upper Level ◽  
Multiple Units

“HAPA” stands for High-Authority Piezoelectric Actuator, which describes high-performance piezoelectric actuators of large stroke and blocking force. “HAPAs” are made possible by high-bending-stiffness connectors that connect multiple units of piezoceramic stacks into a 2-level actuation structure. Present HAPA actuators are fitted with commercial piezoceramic stacks. For instance, a “HAPA-(2+2)” comprises 4 lead zirconate titanate (PZT) stacks, 2 in the upper level with displacement projecting upward and 2 in the lower level with displacement projecting downward. They not only double the axial displacement of individual stacks with only fractional increase in device length but also are of 1.5 to 3 larger blocking force depending on the actual design. “FTA” stands for Flextensional Actuator, in which the horizontal extensional displacement of PZT stacks is amplified to yield much larger contractional vertical displacement via a diamond-shaped elastic frame structure. A range of new FTAs has been developed by us using single or multiple units of PZT stacks, of which the performances are described in this work. “HD-FTA” stands for HAPA-Driven Flextensional Actuator, in which HAPA piezoelectric actuators are used as the motor section to drive diamond-shaped elastic members of various designs for further displacement amplification. Several HD-FTAs, driven by a HAPA-(2+2) actuator, have been developed. Compared with standard FTAs of comparable stroke, HD-FTAs display a higher working load but of smaller overall length. “HAPA”, “FTA”, and “HD-FTA” piezoelectric actuators find applications when a smaller actuator length is advantageous in addition to the required moderate-to-large displacement and working load.

scholarly journals Arrangement of Live Human Cells through Acoustic Waves Generated by Piezoelectric Actuators for Tissue Engineering Applications

2020 ◽  
Vol 10 (10) ◽  
pp. 3477
Author(s):  
Marialaura Serzanti ◽  
Marco Baù ◽  
Marco Demori ◽  
Serena Calamaio ◽  
Manuela Cominelli ◽  
...  
Keyword(s):  
Lead Zirconate Titanate ◽  
Acoustic Waves ◽  
Piezoelectric Actuators ◽  
Lead Zirconate ◽  
Fibrin Clot ◽  
Human Cells ◽  
Al2o3 Substrate ◽  
Resonant Frequencies ◽  
Plate Waves ◽  
Interdigital Transducer

In this paper, the possibility to steer and confine live human cells by means of acoustic waves, such as flexural plate waves (FPWs), generated by piezoelectric actuators applied to non-piezoelectric substrates, has been explored. A device with two lead zirconate titanate (PZT) actuators with an interdigital transducer (IDT) screen-printed on an alumina (Al2O3) substrate has been fabricated and tested. The experimental results show that, by exciting the actuators at their resonant frequencies, FPW modes are generated in the substrate. By exploiting the device, arrangements of cells on lines at frequency-dependent distances have been obtained. To maintain the alignment after switching off the actuator, cells were entrapped in a fibrin clot that was cultured for several days, enabling the formation of cellular patterns.

scholarly journals Loosening Monitoring of the Threaded Pipe Connection Using Time Reversal Technique and Piezoceramic Transducers

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2280 ◽  
Author(s):  
Yabin Liang ◽  
Qian Feng ◽  
Dongsheng Li
Keyword(s):  
Lead Zirconate Titanate ◽  
Time Reversal ◽  
Oil And Gas ◽  
Drill Pipe ◽  
Oil And Gas Industry ◽  
Lead Zirconate ◽  
Pipeline System ◽  
Practical Applications ◽  
Threaded Connection ◽  
Critical Components

Threaded pipe connections are commonly used in the oil and gas industry in particular to connect casting strings, drill pipe strings, production and transportation risers, and pipelines. As the most critical components in the entire chain, maintaining a sealed and secure connection while being subjected to environmental loads and pollution is very important and necessary to reduce potential leakage risk and guarantee the safety of the entire chain. In this paper, an effective approach using time reversal technique and lead zirconate titanate (PZT) transducer was developed to monitor the looseness of the threaded pipe connection. Two threaded pipeline segments connected with a metal coupling were assembled to simulate the threaded connection in the pipeline system. Two PZT patches were mounted on the surface of one pipeline segment and the pipe coupling, respectively. By loosening the threaded connection with different rotation angles, several looseness scenarios were experimentally investigated. For each looseness condition, the developed time reversal-based approach was performed and the corresponding response signal was acquired and analyzed. The experimental results demonstrate that the peak value of the focused signal detected by the PZT sensor decreases with the increase of the looseness degree. The entire test conducted from tightened connection to loosened connection was repeated eight times to validate the repeatability of the developed method and the consistency of the detection results. In addition, the reliability of the developed method was studied by involving high disturbances when the signal was measured. All the test results show that the developed method has a great potential to be employed in practical applications for monitoring the looseness condition of the threaded pipe connection, especially in an environment with severe noises and disturbances.

Acousto-ultrasonics-based health monitoring for nano-engineered composites using a dispersive graphene-networked sensing system

2020 ◽  
pp. 147592172092974
Author(s):  
Yehai Li ◽  
Kai Wang ◽  
Qiang Wang ◽  
Jianwei Yang ◽  
Pengyu Zhou ◽  
...  
Keyword(s):  
Structural Health Monitoring ◽  
Lead Zirconate Titanate ◽  
Health Monitoring ◽  
Lead Zirconate ◽  
Ultrasonic Waves ◽  
Sensing Element ◽  
Engineering Structures ◽  
Practical Applications ◽  
Structural Health ◽  
Sensing System

Sensing is a fundamental yet crucial part of a functional structural health monitoring system. Substantial research has been invested in developing new sensing techniques to enhance sensing efficiency and accuracy. Practical applications of structural health monitoring approaches to real engineering structures require strict criteria for the sensing system (e.g. weight, position, intrusion and endurance), which challenge existing sensing techniques. The boom in nanotechnology has offered promising solutions for the development of new sensing approaches. However, a bottleneck still exists when considering the density of sensors and surface-mounted modality of installation. In this study, graphene nanoparticles are dispersed into a glass fibre/epoxy composite to form a dispersive network sensing system. The piezoresistivity of the graphene-formed network changes locally as a result of the change of inter-nanoparticle distances which triggers the ‘tunnelling effect’ and drives the sensor to respond to propagating elastic waves. Due to the dense graphene network formed within the composite, only a small area is required, functioning as a single sensing element to capture ultrasonic waves. To validate such capability, passive acoustic emission tests and active guided ultrasonic wave tests are performed individually. The graphene-networked sensing system can precisely capture wave signals which contain effective features to identify impact spot or damage location. Integrating passive graphene-formed network and active lead zirconate titanate wafers can form a dense network, capable of fulfilling general structural health monitoring tasks.

Properties of Lead Zirconate Titanate Thick-Film Piezoelectric Actuators on Ceramic Substrates

2006 ◽  
Vol 3 (6) ◽  
pp. 448-454 ◽  
Author(s):  
Darko Belavic ◽  
Marina Santo Zarnik ◽  
Janez Holc ◽  
Marko Hrovat ◽  
Marija Kosec ◽  
...  
Keyword(s):  
Thick Film ◽  
Lead Zirconate Titanate ◽  
Piezoelectric Actuators ◽  
Lead Zirconate ◽  
Ceramic Substrates ◽  
Zirconate Titanate

scholarly journals High strain response and low hysteresis in BaZrO3-modified KNN-based lead-free relaxor ceramics

2021 ◽  
Author(s):  
Jian Zhang ◽  
Zixuan Liu ◽  
Tao Zhang ◽  
Yunfei Liu ◽  
Yinong Lyu
Keyword(s):  
Phase Transition ◽  
Electric Field ◽  
High Strain ◽  
Large Strain ◽  
Piezoelectric Actuators ◽  
Solid State Reaction Method ◽  
Lead Free ◽  
Practical Application ◽  
Practical Applications ◽  
T Phase

Abstract The high driving electric field and the large strain hysteresis was subject to a challenge for piezoelectric actuators’ practical applications. In order to obtain the piezoceramics with giant strain and low hysteresis at small electric field, a ternary solid solution (0.97- x )(K 0.48 Na 0.52 )Nb 0.965 Sb 0.035 -0.03Bi 0.5 (K 0.18 Na 0.82 ) 0.5 ZrO 3 - x BaZrO 3 ( x = 0-0.06) was designed and synthesized by the traditional solid-state reaction method. The relationships among phase transition, microstructure, and electrical properties of the ceramics samples were systemically investigated. Under a low electric field of 4 kV/mm, the ceramic with x = 0.02 obtained a high strain of 0.29 % ( S max / E max = 729 pm/V) and a low hysteresis of 13.8 %. The excellent piezoelectric properties are mainly attributed to rhombohedral-orthorhombic-tetragonal (R-O-T) phase boundary and the relaxor-to-ferroelectric phase transition. We believe that our research can not only provide the pathway of achieving KNN-based ceramics with high strain and low hysteresis but also promote the practical application of lead-free piezoelectric actuators.

scholarly journals Piezoelectric Actuators for Tactile and Elasticity Sensing

Actuators ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 21 ◽  
Author(s):  
Javier Toledo ◽  
Víctor Ruiz-Díez ◽  
Jorge Hernando-García ◽  
José Luis Sánchez-Rojas
Keyword(s):  
Resonant Frequency ◽  
Lead Zirconate Titanate ◽  
Modulus Of Elasticity ◽  
Low Cost ◽  
Piezoelectric Actuators ◽  
Force Sensor ◽  
Lead Zirconate ◽  
Optical Measurements ◽  
Laser Vibrometer ◽  
Electrical Measurements

Piezoelectric actuators have achieved remarkable progress in many fields, being able to generate forces or displacements to perform scanning, tuning, manipulating, tactile sensing or delivering functions. In this work, two piezoelectric PZT (lead zirconate titanate) bimorph actuators, with different tip contact materials, were applied as tactile sensors to estimate the modulus of elasticity, or Young’s modulus, of low-stiffness materials. The actuators were chosen to work in resonance, taking advantage of a relatively low resonant frequency of the out-of-plane vibrational modes, associated with a convenient compliance, proven by optical and electrical characterization. Optical measurements performed with a scanning laser vibrometer confirmed that the displacement per applied voltage was around 437 nm/V for the resonator with the lower mass tip. In order to determine the modulus of elasticity of the sensed materials, the stiffness coefficient of the resonator was first calibrated against a force sensor, obtaining a value of 1565 ± 138 N/m. The actuators were mounted in a positioning stage to allow approximation and contact of the sensor tip with a set of target materials. Electrical measurements were performed using the resonator as part of an oscillator circuit, and the modulus of elasticity of the sample was derived from the contact resonant frequency curve of the cantilever–sample system. The resulting sensor is an effective, low-cost and non-destructive solution compared to atomic force microscopy (AFM) techniques. Materials with different modulus of elasticity were tested and the results compared to values reported in the literature.

Convergent-bceam diffraction studies on lead zirconate titanate Ceramics

1986 ◽  
Vol 44 ◽  
pp. 482-483
Author(s):  
M.L.A. Dass ◽  
T.A. Bielicki ◽  
G. Thomas ◽  
T. Yamamoto ◽  
K. Okazaki
Keyword(s):  
Lead Zirconate Titanate ◽  
Direct Proof ◽  
Lead Zirconate ◽  
Subsolidus Phase ◽  
Pzt Ceramics ◽  
Subsolidus Phase Diagram ◽  
Zirconate Titanate ◽  
Two Phases ◽  
Cbd Method ◽  
Titanate Ceramics

Lead zirconate titanate, Pb(Zr,Ti)O3 (PZT), ceramics are ferroelectrics formed as solid solutions between ferroelectric PbTiO3 and ant iferroelectric PbZrO3. The subsolidus phase diagram is shown in figure 1. PZT transforms between the Ti-rich tetragonal (T) and the Zr-rich rhombohedral (R) phases at a composition which is nearly independent of temperature. This phenomenon is called morphotropism, and the boundary between the two phases is known as the morphotropic phase boundary (MPB). The excellent piezoelectric and dielectric properties occurring at this composition are believed to.be due to the coexistence of T and R phases, which results in easy poling (i.e. orientation of individual grain polarizations in the direction of an applied electric field). However, there is little direct proof of the coexistence of the two phases at the MPB, possibly because of the difficulty of distinguishing between them. In this investigation a CBD method was found which would successfully differentiate between the phases, and this was applied to confirm the coexistence of the two phases.

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