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Dissertations / Theses on the topic 'Piezoelectric Actuators'

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Published: 4 June 2021
Last updated: 7 July 2024

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1

Hack, Thorsten. "Stick-slip piezoelectric actuators." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624403.

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2

Haigh, Richard. "Novel piezoelectric thick film actuators." Thesis, Cranfield University, 2005. http://dspace.lib.cranfield.ac.uk/handle/1826/3814.

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Planar-spiral piezoelectric-unimorph-actuators, that deflect out-of-their-plane, were modelled, designed and fabricated. A range of other planar piezoelectric-device designs has also been made. These include spokes, multi-arms, plates and swastikas. All these devices consisted of a mechanical support in the plane with a piezoelectric layer deposited on top. Impedance spectra demonstrated that a fabricated device was piezoelectrically active. Finite-element (FE) models of straight and spiral piezoelectric- unimorph-actuators were constructed. The mechanical stiffness of the spiral-beam was increased with the curvature of the beam; consequently, the inner coils exhibited virtually no deflection and appeared to be redundant. The advantage of the spiral-actuators is that they allow large actuator lengths to be contained compactly without the loss of mechanical stiffness. Fabrication of the above devices necessitated the development of new fabrication technologies. The active-piezoelectric and mechanical-support were a lead zirconate titanate (Pb(Tii_XZrx)O3 - PZT) thick-film and a-platinised-silicon-wafer respectively. Vias were opened in the PZT with wet etching, and this was completed without damaging the back electrode. Powder blasting allowed any 2-dimensional-shape to be cut into the device wafer. Devices were released from the Si support with deep-reactive-ion-etching (DRIE). The PZT thick films were fired with a Cu20-PbO eutectic additive. Pb and Cu were considered to dope on A and B lattice sites (of PZT) respectively, when the PZT was sintered at high oxygen-partial-pressure (p02). The electrical conductivity of PZT thick films was increased when they were sintered at low P02, and this was moderated by the presence of Cu' as an acceptor ion. A lead-platinum intermetallic and lead silicate glass phase simultaneously formed under sintering conditions of low pot, and this simultaneous formation, was accounted for by a six-stage mechanism. Step 1, residual C in the thick film reduces PbO to Pb followed by step 2 where Pb diffuses into the Pt back electrode. In step 3, Pt3Pb formation occurs in the intermetallic layer followed by step 4 in which PtPb forms. Step 5 occurs with saturation of the intermetallic layer as Pb continues to diffuse from the thick film. There is additional diffusion of Pb into the underlying Si substrate. Finally step 6 occurs at some later point, when P02 has risen, Pb is oxidised to PbO, and Si is oxidised to Si02. PbO and Si02 can flux to form PbSiO3 The glass was found to undermine film/substrate adhesion.
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3

Gomis-Bellmunt, Oriol. "Identification and control of piezoelectric actuators." Saarbrücken VDM Verlag Dr. Müller, 2007. http://d-nb.info/988454696/04.

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4

Spangler, Ronald L. 1964. "Piezoelectric actuators for helicopter rotor control." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14462.

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5

Arnau, Cubillo Albert. "Contributions to aerostructures morphing with piezoelectric actuators." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/669624.

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Since the first models developed in the late 19th century, the applications of piezoelectric materials have been progressively growing in number. The capacity of these materials to couple electric and mechanic fields makes them perfect candidates in the study of geometrical morphing. Their application in aeronautical products has been traditionally seen from two different perspectives: their use as sensors and as actuators. Both functions present potential benefits and improvements with promising applications. While the investigations in the past years focused mainly in the analysis and integration of piezoelectric materials in structures as means of implementing what is known as structural health monitoring systems, the application of this type of materials as actuators in the geometrical control of structures also awakes interest in the scientific community. In its present state of development, the technology for morphing of structures using piezoelectric actuators is not yet advanced enough as to integrate such systems in commercial products. However, the field is in continuous development and the evolution of the materials and the integration solutions bring the technology closer to industrial application. This thesis aims at studying the feasibility of application of piezoelectric-actuated morphing aeronautical structures in current aircraft concepts. The analysis is performed at theoretical and experimental levels analyzing the static and dynamic performance of currently available actuators and motion amplification technologies. The research presented in this thesis is directed in two different applications of utilization of the actuators: as static actuators producing deformation of the aerodynamic surface and as dynamic actuators controlling a classic aerodynamic control surface. In each of the applications a different type of piezoelectric actuator architecture has been used: a piezoelectric patch has been selected for static morphing applications and a piezoelectric stack-based actuation system for the dynamic control of the conventional control surface. The static experiments performed aimed at demonstrating the suitability of piezoelectric actuators as morphing devices. This analysis was performed analyzing the deflections produced in the trailing edge of an aerodynamic profile. The analysis of the obtained experimental results showed promising results as the actuating configurations managed to perform as designed. The static experiments showed substantial deformation of the trailing edge of the wing profile making this configuration mature enough for further experimentation such as wind tunnel testing. The deflections produced were, however, not significant enough for the direct application of the solution into larger scale configurations. Scalability of the technological solutions remains one of the major challenges of the technology in the morphing applications. The dynamic results showed good performance of the actuators in an anti-flutter demonstrator application during wind tunnel testing. The experiments showed that the system remained stable well passed the flutter velocity; this allows for further experimentation in structures presenting higher flutter speeds. With the development of the next generation of advanced piezoelectric ceramics, with piezoelectric coefficients twice as large in comparison to PZT-based ceramics, the application of the deforming structure concept is very promising for application in larger demonstrators in both static and dynamic applications. The next generation of piezoelectric materials presents itself as a first step into a solution to the scalability of the technology for application into full-scale demonstrators.
Des dels primers models desenvolupats durant el segle XIX, les aplicacions per a materials piezoelèctrics han anat creixent progressivament. La relació que presenten aquests materials entre el comportament mecànic i el comportament elèctric els converteix en candidats ideals en l'estudi d'estructures deformables. L'aplicació de piezoelèctrics en aeronàutica es concep tradicionalment des de dues perspectives: com a sensors o com a actuadors. Ambdues presenten potencials beneficis i aplicacions. Tot i que en els últims anys la recerca s'ha concentrat en l'estudi d'integració dels materials en sistemes que permeten controlar la salut de l'estructura (Structural Health Monitoring), l'aplicació de piezoelèctrics com a actuadors d'estructures deformables desperta l'interès de la comunitat científica. En l'estadi actual, la tecnologia necessària per deformar estructures de forma controlada utilitzant materials piezoelèctrics no està suficientment desenvolupada. No obstant, la recerca en aquest camp està en continu desenvolupament i s'apropa a solucions que permetran integrar-la en aplicacions industrials. L'objectiu de la tesi és estudiar la possibilitat d'utilitzar deformacions produïdes mitjançant actuadors piezoelèctrics en estructures aeronàutiques actuals. L'anàlisi està orientat des de punts de vista teòric i experimental i es centra en el comportament estàtic i dinàmic de solucions tecnològiques amb actuadors i tecnologies d'amplificació disponibles comercialment. La recerca que es presenta en la tesi estudia dues aplicacions diferents en l'ús d'aquest tipus d'actuadors: com a actuadors en regim estàtic, produint deformacions de la superfície aerodinàmica, i com a actuadors dinàmics, que controlin una superfície de control convencional. L'arquitectura de la solució tecnològica emprada ha estat diferent en cada aplicació: en la deformació estàtica de la superfície aerodinàmica l'actuador és de tipus "patch" mentre que en el cas dinàmic és de tipus "stack". Els experiments estàtics desenvolupats tenen com a objectiu demostrar la capacitat dels piezoelèctrics com a elements que produeixin deformacions en l'estructura (morphing). Aquest objectiu es demostra analitzant les deflexions produïdes en el caire de fuga d'un perfil aerodinàmic. Els resultats experimentals obtinguts són optimistes ja que les diferents configuracions d'actuadors es comporten tal i com prediuen els models. En règim estàtic, les deformacions produïdes en el caire de fuga son substancials. Això permet assegurar que la configuració utilitzada en els experiments és prou madura com per seguir investigant, per exemple, en túnel de vent. Malgrat això, les deformacions produïdes encara no són suficientment significatives com per integrar l'experiment en un model més gran. L'escalabilitat és un dels reptes més importants que presenta la tecnologia en aplicacions de "morphing". Els resultats dinàmics demostren una bona actuació de l'actuador integrat en un sistema anti-flameig en els experiments en túnel de vent. Els experiments demostren la capacitat del sistema de mantenir-se estable a velocitats mes enllà de l'aparició del flameig. El següent pas en aquesta línia de recerca es l'investigació en models més complexos en quant a aparició de flameig. Amb el desenvolupament d'una nova generació de materials piezoelèctrics ceràmics avançats, que promet coeficients piezoelectrics el doble d'alts en comparació amb els materials basats en PZT disponibles actualment, l'arquitectura experimentada en règim estàtic és un molt bon candidat en aplicacions a escala més gran. Aquesta propera generació de materials es presenta com un primer pas en solucionar els problemes d'escalabilitat que presenta la tecnologia actualment.
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6

Brünahl, Jürgen. "Physics of piezoelectric shear mode inkjet actuators." Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3535.

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This thesis describes work on piezoelectric shear modeactuators used in dropon- demand ink printing applications.These actuators comprise an array of ink channels micromachinedinto bulk Pb(ZrxTi1-x)O3(PZT) ceramics.

During this study, a new pulsed spectroscopic technique wasdeveloped to investigate functional properties of a singlechannel wall of the actuator. The pulse technique is based onrecording the transient current in response to a short voltagepulse applied to the channel wall. An electric field appliedperpendicular to the polarization will cause a shear motion ofthe wall. If a voltage pulse with a fast rise time is highenough in amplitude to actuate the wall, it will act like atuning fork and oscillate at it’s resonant frequencies.Because of the piezoelectric effect, the mechanicaloscillations of the wall can be seen as oscillations in thetransient current.

Beside the pulsed technique, dielectric spectroscopy,ferroelectric hysteresis loop tracing and stroboscopy were usedas characterization techniques. The results obtained arediscussed in respect to temperature dependence, frequencydispersion, ferroelectric fatigue and acoustic resonancemodes.

Another field of interest was the temperature inside theactuator. An electric circuit, based on the voltage dividerprinciple, was built to monitor the ink temperature as afunction of the printing pattern.‘Dummy walls’,located at the beginning and the end of the channel wall array,were used as temperature sensing elements. Since the dielectricpermittivity of the PZT channel walls depends on temperature,the capacitance of the‘dummy walls’changes withtemperature. The information obtained by this measurementtechnique was used to investigate alternative materials for thepassive components of the actuator.

A further part was the development of a new actuator designcalled a‘Chevron actuator’. Chevron actuatorsinclude an additional PZT layer with polarization in theopposite direction to the base plate polarization. Thus, thewhole channel wall is used as the active part instead of usingjust the upper half as in the standard actuator. The mainadvantage of this technique is a reduced power consumption ofthe actuator and therefore less heat dissipation.

Different approaches were used to construct Chevronactuators. Experiments determined the efficiency of theactuators and these results were used to make improvements. TheChevron actuators were characterized by the above mentionedtechniques and compared with standard Xaar actuators.

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7

Mansoor, Muhammad bin [Verfasser], Peter [Akademischer Betreuer] Woias, and Frank [Akademischer Betreuer] Goldschmidtböing. "Nonlinear resonant piezoelectric actuators for turbulence manipulation." Freiburg : Universität, 2019. http://d-nb.info/1192660803/34.

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8

Baillargeon, Brian P. "Active Vibration Suppression of Smart Structures Using Piezoelectric Shear Actuators." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/BailargeonBP2003.pdf.

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9

Almajid, Abdulhakim A. "Design of high performance piezo composites actuators /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/7130.

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10

Anusha, Anisetti. "Non-linear Shunting of Piezo-actuators for Vibration Suppression." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1208834134.

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11

Wolf, Kai-Dietrich. "Electromechanical energy conversion in asymmetric piezoelectric bending actuators." [S.l. : s.n.], 2000. http://elib.tu-darmstadt.de/diss/000094/d.pdf.

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12

Ghaeadi, Sirous K. "Control of vibrations of shells using piezoelectric actuators." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0018/NQ55333.pdf.

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13

Owens, Sam. "Thick-film piezoelectric bimorph actuators for MEMS devices." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/7018.

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Active ow control can be used to improve the aerodynamic e ciency of passenger aircraft, road tra c and wind turbines amongst other applications. This work describes the fabrication of an ultra-compact microvalve that has been designed as part of an active aerodynamic ow control system that generates airjets of a scale and velocity that have been shown to have desirable e ects on the macroscopic air ow. The design of the microvalve is based on criteria speci ed by the requirements of active ow control and the piezoelectric bimorph actuator which opens and closes the valve outlet. Cont/d.
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14

Warkentin, David J. "Power amplification for piezoelectric actuators in controlled structures." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11508.

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15

Neal, Devin Michael. "Large-strain piezoelectric actuators using controlled structural buckling." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55282.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 59-60).
Buckling is a highly nonlinear and singular phenomenon in thin beams, and is usually an undesired characteristic that must be prevented from occurring in engineered systems. Buckling, however, can be a useful mechanism for gaining extremely large displacement amplification, since a infinitesimal displacement in the axial direction of the beam may lead to a large deflection in the middle of the beam. This thesis presents a novel large-strain piezoelectric actuator exploiting the buckling of a structure with imbedded piezoelectric stack actuators. The realization of this buckling actuator began by rethinking the paradigm of where PZT stacks are placed in traditional flexure-based displacement amplification mechanisms. Although the free displacement of a PZT stack is only 0.1% of the stack length, the buckling mechanism can produce a large bipolar displacement that is approximately 150 times larger than the original PZT displacement. Furthermore, the structural buckling produces a pronounced nonlinearity in output impedance; the effective stiffness viewed from the output port varies as a function of output displacement, which can be a useful property for those applications where actuator stiffness needs to vary. Buckling is controlled with phased activation of the input units and either 1) a strategically placed redirecting stiffness or 2) multiple buckling units working in parallel.
by Devin Michael Neal.
S.M.
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16

Aimmanee, Sontipee. "Deformation and Force Characteristics of Laminated Piezoelectric Actuators." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11219.

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This research discusses the mechanical characteristics of laminated piezoelectric actuators that are manufactured at an elevated temperature, to cure the adhesive bonding the layers together, or to cure the layers made of polymeric composite material, and then cooled to a service temperature. Mainly discussed are actuators that are composed of layers of passive materials and a layer of piezoelectric material. THUNDER (THin layer UNimorph ferroelectric DrivER and sensor) and LIPCA (LIghtweight Piezo-composite Curved Actuator) actuators, which consist of layers of metal, adhesive and piezoelectric material, and carbon-epoxy, glass-epoxy and piezoelectric material, respectively, are studied and investigated in detail to understand the thermal effects due to the elevated manufacturing temperature. Owing to the large out-of-plane deformations of the THUNDER actuators as a result of cooling to the service temperature, inclusion of geometric nonlinearities in the kinematic relations is taken into consideration for prediction of the thermally-induced deformations and residual stresses. The deformations and residual stresses are predicted by using a 23-term Rayleigh-Ritz approach and more rigorous, time-consuming, finite-element analyses performed with ABAQUS. The thermally-induced deformations of THUNDER actuators can result in multiple room-temperature manufactured shapes, whereas those of LIPCA actuators (LIPCA-C1 and LIPCA-C2) exhibit single room-temperature manufactured shape. Actuation responses of these actuators caused by a quasi-static electric field applied to the piezoelectric layer are also studied with the Rayleigh-Ritz approach. It is shown that geometrical nonlinearities play an important role in the actuation responses, and these nonlinearities can be controlled by the choice of actuator geometry and the materials in the passive layers. In addition, blocking forces representing load-carrying capability of THUNDER and LIPCA actuators are determined. Support conditions and again geometrical nonlinearities are vital factor in load-resisting performances. Amongst the actuators considered, the actuated deflection and blocking forces are compared. Finally, based on the outcome of this study, new criteria for designing a new type of laminated piezoelectric actuators with improvement of performance characteristics are proposed.
Ph. D.
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17

Nale, Kumar S. "Multiplexed Control of Smart Structure using Piezoelectric Actuators." Cleveland State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=csu1231281641.

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18

Mouhli, Makram. "ANALYSIS AND SHAPE MODELING OF THIN PIEZOELECTRIC ACTUATORS." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/1552.

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The field of smart materials is an increasingly growing area of research. In aerodynamics applications especially, transducers have to fulfill a series of requirements such as light weight, size, energy consumption, robustness and durability. Piezoelectric transducers, devices which transform an electrical signal into motion, fulfill many of these requirements. Specifically, piezoelectric composites are of interest due to their added toughness and ease of integration into a structure. Resulting composites have a characteristic initial curvature with accompanying residual stresses that are responsible for enhanced performance, relative to flat actuators, when the active material is energized. A number of transducer designs based on composites have been developed. Two of these piezoelectric composites called Thunder® and Lipca are analyzed. Thunder is a composite of steel, polyimide adhesive, PZT, polyimide adhesive, and aluminum; and Lipca is a composite of fiberglass epoxy, carbon/epoxy, PZT, and fiberglass epoxy.Room temperature shapes of circular and rectangular Thunder® and Lipca actuators are predicted by using the Rayleigh-Ritz model. This technique is based on the assumption that the stable geometric configuration developed in the actuator after manufacturing, is the configuration that minimizes the total potential energy. This energy is a function of the displacement field which can be approximated by two functions, a four term model, and a twenty-three term model. The coefficients in the models are determined by minimizing the total potential energy of the actuator. The actuator deformations are assumed to obey the Kirchhoff hypothesis and the actuator layers are assumed to be in the state of plane stress.The four coefficient model produces results not comparable to three-dimensional surface topology maps. The twenty-three coefficient model however, is shown to have generally good agreement with the data for all studied actuators. To quantify the difference, at the cross section of each actuator, a profile is fitted by using a quadratic equation obtaining regression coefficients above 99%. For all actuators, the error between experimental and the calculated centerline data is less than 6%. For the 6R model however, the error is approximately 25%. One of the possible reasons for the error may be the tolerance of the thickness of the PZT layer. By changing the PZT thickness ±6% of the nominal value, over predicts the experimental dome height by 20%. Another possible reason for the discrepancy is the thickness of the actuator, thicker than all actuators used in this study, which might contradict the validity of the thin actuator assumption. Furthermore, by calculating the side-length-to-thickness ratio, 115 in this case, as stated by Aimmanee & Hyer (2004), may cause instability, and could result in unexpected behavior.The neutral axis position, calculated by using a force balance at equilibrium under the assumption of pure bending, for all actuators used in this study is determined and compared to the ceramic layer position. The results indicated that for all Thunder® models the neutral axis is located below the ceramic layer indicating that the PZT wafer may be in total tension. For the Lipca C2 device however, the neutral axis is found to be above the ceramic layer, indicating that the piezoelectric layer may be in total compression.Strain fields are also predicted with contradicting results when compared to the theory that the ceramic is in tension in the Thunder actuators. The contradiction on the strain calculations can be explained by the manner the strain field is derived: by differentiating and squaring the high-order polynomials of the approximated displacement component losing accuracy when it comes to predicting normal and shear strains.The Rayleigh-Ritz technique can become a tool to perform parametric studies of the key elements for manufacturing to optimize specific features of the actuators.
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19

ORAZI, MATTEO. "Bluff Bodies Flow Control using Innovative Piezoelectric Actuators." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2562349.

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An active flow control technique based on “smart-tabs” is proposed to delay flow separation on a circular cylinder and on a simplified bi-dimensional automotive geometry body. The actuators are retractable and orientable multilayer piezoelectric tabs which protrude perpendicularly from the model surface. They are mounted along the spanwise direction with constant spacing. The effectiveness of the control was tested in pre-critical and in post-critical regime by evaluating the effects of several control parameters of the tabs like frequency, amplitude, height, angular position and plate incidence with respect to the local flow. Measurements of the mean static pressure distribution around the cylinder were used to estimate the pressure drag and lift coefficient. To take into account friction and the parasite drag of the actuators wake analysis was performed. The maximum drag reduction achieved in the pre-critical regime was of the order of 30%, whereas in the post-critical regime was about 15%, both for the highest forcing available. In pre-critical condition the active forcing plays an important role on drag and pressure fluctuations reduction. Spectral analysis of the signals from instantaneous pressure transducers (electret microphones) indicated an almost complete suppression of the vortex shedding in active forcing conditions. In post-critical regime, instead, most of the effects are due to passive forcing limiting the active contribution to a maximum of 3%. The results related to the automotive geometry confirm the ones obtained on the circular cylinder, with a maximum attained drag reduction of 13.4% with only small contributions due to active forcing. To evaluate the potentialities of the smart-tabs in real applications power absorption measurements are reported together with energy budget considerations. Finally, the identification of the key non-dimensional control parameters, was performed.
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20

Leroy, Edouard. "Miniature ultrasonic piezoelectric actuators for compact spherical motors." Palaiseau, Ecole polytechnique, 2013. https://pastel.hal.science/docs/00/92/74/17/PDF/These_finale_compressed.pdf.

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Les moteurs à plusieurs degrés de liberté angulaire sont des systèmes utilisés dans de nombreuses applications avec par exemple la réalisation d'articulation de robots, de roues omnidirectionnelles ou la stabilisation de composants optiques. La méthode classiquement utilisée pour réaliser ce type de plateformes limite cependant la capacité de ces systèmes à être miniaturisés. Une solution facilitant la réalisation de systèmes compacts à plusieurs degrés de liberté angulaire est l'utilisation d'un unique rotor sphérique. Nous proposons dans ce travail, un actionneur ultrasonique piézoélectrique adapté à la fabrication de moteurs sphériques compacts. L'innovation de l'actionneur développé tient dans l'adaptation de sa surface de contact au rotor, ce qui permet d'obtenir une surface étendue de contact et un guidage total du rotor sphérique. L'état de l'art des différents systèmes d'actionnement sphérique à un seul rotor est proposé ainsi que l'ensemble des considérations théoriques utiles à la modélisation et la réalisation de moteurs ultrasoniques. Un modèle complet pour la conception d'actionneurs ultrasoniques est proposé, il décrit l'étude de la géométrie et de ses modes de vibration, l'analyse du contact par l'application d'un modèle de transfert de force et la conversion électromécanique par méthodes semi-analytiques. Un prototype expérimental est proposé ainsi qu'une caractérisation de ses performances. Les données obtenues sont comparées au modèle théorique et permettent de valider les méthodes de conception proposées. L'effet de l'amplitude de stimulation, de la précontrainte et de l'étendue du contact y sont notamment analysés. Bien qu'appliqué au cas particulier d'un actionneur multimode incurvé, la démarche employée est générale et peut-être adaptée à la réalisation d'autres systèmes ultrasoniques
Multi-degree-of-freedom angular motors are used in numerous applications, such as robot articulations, omnidirectional wheels or the stabilization of optical components. Nevertheless, the classical method used to build such platforms limits the miniaturization of these devices. The use of a single spherical rotor is a solution which facilitates the realization of compact multi-degree-of-freedom angular systems. In this work, we propose a piezoelectric ultrasonic actuator adapted to the fabrication of compact spherical motors. The novelty of the developed actuator is the adapted contact surface that allows for an extended contact area and thus the complete guidance of a spherical rotor. The state of the art of single rotor spherical systems is presented along with a presentation of the theoretical considerations useful for the modeling and construction of ultrasonic motors. A complete model for the design of ultrasonic motors is also proposed, which describes the geometry of the actuator and its vibration modes, the analysis of the contact using a force transfer model and the electromechanical conversion using semi-analytical methods. An experimental prototype is proposed along with a characterization of the actuator performance. Experimental data is compared to the theoretical model and validates the proposed design method. Parameters such as electrical amplitude, preloading force and the extent of the contact area are analyzed. Although in this case we demonstrate the application of our design methodology to the specific case of a curved multi-mode actuator, the proposed methodology is general and can be adapted to the design of other ultrasonic systems
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21

Hills, Zachary Patrick. "Using Macro-Fiber Composite Actuators for Aquatic Locomotion." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/42818.

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The research presented herein aims to develop a bio-inspired swimming system for an autonomous underwater vehicle using Macro-Fiber Composite (MFC) actuators. The swimming system draws inspiration from the motion of carangiform fish, which limit their body motion while rapidly oscillating their caudal tail fin. The foundation for the bio-inspired swimming system is built upon a composite cantilever beam with MFC actuators in bimorph configuration. The MFC actuators excite the composite beam near its fundamental natural frequency to produce thrust as the vibration transfers momentum to the surrounding fluid. An analytical model that incorporates Euler-Bernoulli beam theory, linear piezoelectricity, and fluid mechanics is developed to predict the thrust generated by the beam vibration. Experimental testing is performed to verify aspects of, as well as recommend corrections to, the analytical model. A prototype carangiform swimmer is developed that employs a passive caudal tail fin to alter the vibratory motion of the system from a beam vibration mode to one more resembling carangiform swimming. This device is subjected to experimental testing to determine the swim speeds it is able to achieve. A maximum velocity of 90mm/s was observed when the system is excited at 900V. However, better performance may be achieved by increasing the excitation voltage.
Master of Science
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22

Hopkinson, David P. "Development of stress gradient enhanced piezoelectric composite unimorph actuators." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/16372.

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23

Malik, Nihal S. "Adaptive vibration control of flexible structures using piezoelectric actuators." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509770.

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24

Zhong, Jinghua. "Modeling and adaptive robust motion control of piezoelectric actuators." Thesis, Purdue University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3636707.

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High performance motion trajectory tracking can be achieved on a piezoelectric stack actuator stage by the combination of a new hysteresis model, judicious modeling of the dominant dynamics, and adaptive robust control design.

A new hysteresis model for piezoelectric actuators is proposed. Inspired by the similarity between pre-sliding friction and piezoelectric hysteresis, the Dahl friction model is extended with non-local memory to model piezoelectric hysteresis. Asymmetry in hysteresis loops is accommodated with a shaping function, which eliminates the need for having different parameters for different branches of the hysteresis loops. All parameters of the hysteresis model can be identified from the outer-loop alone, and the identified model reduces hysteresis nonlinearity from 14 percent of the actuator range to less than 1 percent.

A low-order dynamic model is developed by recognizing the domain switching dynamics of the actuator as the dominant dynamics when the resonant frequency of the stage is far beyond the application bandwidth. The piezoelectric dynamics is well approximated by a feed-through gain and a first-order nonlinear dynamics driven by the input with hysteretic disturbances.

Based on the parameterized model, an adaptive robust controller is designed to achieve (a) guaranteed transient error under the assumption of bounded uncertainties and disturbances; and (b) asymptotic tracking in the presence of parametric uncertainties only. Good tracking performance is achieved for large amplitude trajectories up to 100 Hz even when the hysteresis is entirely attenuated as an unknown disturbance. With additional model compensation from the hysteresis model, the final tracking errors are more than two orders of magnitude smaller than previously reported in literature on an identical actuator.

For single-loop periodic trajectories, performance can be improved without using an explicit hysteresis model. By approximating the unknown but periodic uncertainty with harmonic basis functions and adapting their amplitudes online, non-parametric uncertainty from unknown hysteresis is significantly reduced. Experimental results demonstrate tracking error down to the sensor noise level for sinusoidal trajectories up to 100 Hz with moderate amplitudes and less than one percent for large amplitudes.

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25

Stampleman, David Scott. "Active microgravity vibration isolation using PVDF polymer piezoelectric actuators." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/42477.

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26

Kabeya, Kazuhisa III. "Structural Health Monitoring Using Multiple Piezoelectric Sensors and Actuators." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36709.

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A piezoelectric impedance-based structural health monitoring technique was developed at the Center for Intelligent Material Systems and Structures. It has been successfully implemented on several complex structures to detect incipient-type damage such as small cracks or loose connections. However, there are still some problems to be solved before full scale development and commercialization can take place. These include: i) the damage assessment is influenced by ambient temperature change; ii) the sensing area is small; and iii) the ability to identify the damage location is poor. The objective of this research is to solve these problems in order to apply the impedance-based structural health monitoring technique to real structures. First, an empirical compensation technique to minimize the temperature effect on the damage assessment has been developed. The compensation technique utilizes the fact that the temperature change causes vertical and horizontal shifts of the signature pattern in the impedance versus frequency plot, while damage causes somewhat irregular changes. Second, a new impedance-based technique that uses multiple piezoelectric sensor-actuators has been developed which extends the sensing area. The new technique relies on the measurement of electrical transfer admittance, which gives us mutual information between multiple piezoelectric sensor-actuators. We found that this technique increases the sensing region by at least an order of magnitude. Third, a time domain technique to identify the damage location has been proposed. This technique also uses multiple piezoelectric sensors and actuators. The basic idea utilizes the pulse-echo method often used in ultrasonic testing, together with wavelet decomposition to extract traveling pulses from a noisy signal. The results for a one-dimensional structure show that we can determine the damage location to within a spatial resolution determined by the temporal resolution of the data acquisition. The validity of all these techniques has been verified by proof-of-concept experiments. These techniques help bring conventional impedance-based structural health monitoring closer to full scale development and commercialization.
Master of Science
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27

Bolzmacher, Christian. "Miniaturized piezoelectric actuators for high-speed flow control applications." Palaiseau, Ecole polytechnique, 2010. http://www.theses.fr/2010EPXX0071.

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En français : Cette thèse décrit le développement d'actionneurs piézoélectriques miniaturisés pour le contrôle actif d'écoulement à haute vitesse. L'objectif est de retarder la transition laminaire turbulente par le contrôle actif des ondes de Tollmien-Schlichting par introduction d'ondes artificielles à phase inversée. Le premier concept étudié dans cette thèse est un actionneur amplifié mécaniquement avec une structure de type levier élastique situé au-dessus d'une céramique piézoélectrique. Les avantages de cet actionneur sont le contrôle direct, la fonction de transfert linéaire, et le temps de réponse très rapide, ce qui facilite l'intégration dans un système asservi. Le deuxième concept est basé sur l'utilisation d'une membrane conique actionnée par un anneau piézoélectrique dans un mode propre axisymétrique. La géométrie conique focalise les ondes générées par l'anneau piézoélectrique vers le centre ou les amplitudes sont le plus importantes. Pour le control des ondes de Tollmien-Schlichting, la modulation d'amplitude est appliquée pour atteindre une gamme de fréquence large ou la fréquence porteuse est délivrée par les modes propres. Cet actionneur à l'avantage d'utiliser une membrane robuste fermée et une intégration simple. L'effet des actionneurs sur l'écoulement a été mesuré avec des capteurs film chaud dans une soufflerie en boucle ouverte. Pour les dimensions des actionneurs adaptés sur l'écoulement, l'effet désiré pour le contrôle actif de la transition a été observé. Enfin, il a été démontré que la modulation d'amplitude est une alternative intéressante si la fréquence porteuse est sélectionnée de manière optimale pour qu'elle n'agisse pas sur l'écoulement (> 40kHz)
This work describes the development of miniaturized piezoelectric actuators for high-speed flow control on airfoils. The goal is to delay the laminar-turbulent transition by active wave cancellation of so-called Tollmien-Schlichting waves introducing appropriate counterwaves. The first design concept is based on a mechanically amplified actuator where an external elas-tic lever-type amplification unit is located above a piezoelectric disc. This actuator provides direct control ability, a linear transfer function, and fast response time facilitating its integra-tion in controller systems. The second design concept is based on a tapered membrane driven in one of its axisymmetric eigenmodes, excited by a piezoelectric ring placed at the outer edge. The tapered membrane focuses the induced waves to the centre, where maximum amplitudes can be observed. Ampli-tude modulation allows the actuator to attain a wide frequency range as required for active cancellation of Tollmien-Schlichting waves, where the carrier frequency is provided by the eigenfrequencies. Its robustness, simple fabrication, and closed surface qualify this actuator for aircraft implementation. The effect of both actuators on the airflow around a wing profile at open-loop control has been measured with hot-film anemometers during a wind tunnel experiment. For device di-mensions adapted to the flow conditions both actuators exhibit the desired effect on the air-flow required for active transition control. It has been shown that amplitude modulation is an option for this type of flow control if the carrier frequency is selected adequately (>40 kHz) in order to not disturb the airflow
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28

McCray, Thomas Wade. "Construction and characterization of removable and reusable piezoelectric actuators." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06232009-063342/.

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29

Green, Stephen Marcus 1957. "Manipulation of a rectangular air jet using piezoelectric actuators." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278089.

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An air jet emanating from a rectangular conduit with exit plane dimensions 7.62 cm x 1.27 cm (aspect ratio 6:1) is forced using four piezoelectric actuators mounted along the long sides of the jet opening. Excitation is effected via amplitude modulation of the resonant carrier waveform. Although the flow is not normally receptive to excitation at the actuator resonance frequency, if the excitation amplitude is high enough, spreading of the forced segments of the jet shear layer can lead to a significant deflection of the jet column. When the amplitude modulated excitation is high enough, the input waveform is effectively demodulated by a nonlinear process related to the formation and coalescence of nominally spanwise vortices. The resulting effect is the spatial amplification and attenuation of the modulation and resonant wavetrains, respectively. The choice of different spatial/temporal wavetrains can result in the excitation of spanwise and streamwise instabilities of the jet column.
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30

FORLANI, Mauro. "Investigation on the dynamic performances of piezoelectric multilayer actuators." Doctoral thesis, Università degli studi di Bergamo, 2011. http://hdl.handle.net/10446/875.

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31

Swathanthira, Kumar Murali Murugavel Manjakkattuvalasu. "Implementation of an actuator placement, switching algorithm for active vibration control in flexible structures." Link to electronic thesis, 2002. http://www.wpi.edu/Pubs/ETD/Available/etd-1120102-210634.

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Thesis (M.S.)--Worcester Polytechnic Institute.
Keywords: Actuator placement algorithm; piezoelectric actuators; LQR; Galerkin; supervisory control; active vibration control; FEA; switching policy; dSPACE. Includes bibliographical references (p. 58-64).
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32

Qiu, Yan. "Distributed piezoelectric actuator with complex shape." Thesis, Peninsula Technikon, 2002. http://hdl.handle.net/20.500.11838/1263.

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Thesis (MTech (Mechanical Engineering))--Peninsula Technikon, Cape Town, 2002
Distributed Piezoelectric Actuator (DPA) is one kind of actuator in the smart technology field. Firstly, DPA is one kind of solid-state actuator, and can be embedded in the structure. Secondly, it can be controlled by the electrical signal with high bandwidth and high precision. So it can be applied in the many different fields, such as high-resolution positioning, noise and vibration detection and shape control. Up to now, all of the DPA theory investigations and the product designs are based on applying the approximate electrical field. And only the rectangular shape DPA has been studied. The accurate distribution and intensity of electrical and mechanics field, and the numerical imitation for the DPA products with rectangular and other shapes have never been discussed and studied. Therefore, the development of DPA to be used in the micro application, such as in the Micro Electro-Mechanical System (MEMS), has been limited. This thesis has developed the analytical analysis models for two types of DPA elements and the part circular shape DPA element. The MathCAD and MATLAB program have been used to develop the analytical models. The ABAQUS program has also been used to compare the results between the analytical models and Finite Element Method (FEM). Finally, the accuracy and reliability of analytical models have been proved by results comparison between the analytical models, FEM and the product testing data from the industry. This thesis consists of five chapters. Chapter 1 is the introduction of smart structure. The characterizations of constituent materials, including the piezoelectric material and matrix epoxy material have been discussed in Chapter 2. In Chapter 3, the analytical models for two type of DPA element have been developed and the comparisons have also been completed. The analytical models for part circular shape DPA element have been developed in Chapter 4. The conclusions and recommendations are included in Chapter 5.
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33

Mewer, Richard C. "Analysis and Structural Health Monitoring of Composite Plates with Piezoelectric Sensors and Actuators." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/MewerRC2003.pdf.

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34

Webber, Kyle Grant. "Characterization of Actuation and Fatigue Properties of Piezoelectric Composite Actuators." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7127.

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Epoxy composite laminated piezoelectric stress-enhanced actuators (ECLIPSE) have been developed for potential applications by the United States Air Force and others. This class of actuators offers several advantages over other unimorph actuators such as lighter weight, design flexibility, and short production time. Anisotropic differential thermal expansion is utilized in the design of the actuators to achieve large out-of-plane curvature and place the brittle piezoelectric ceramic in residual compression. The numerous composite material choices and configurations can be used to control characteristics of the actuator such as radius of curvature and force output. ECLIPSE actuators were characterized during this study. They were made from layers of Kevlar 49/epoxy composite and a lead zirconate titanate ceramic (PZT) plate. All ECLIPSE actuators tested were built with a PZT plate with the same dimensions and material, but had different layup configurations. By changing the stacking order of the composite and PZT material, characteristics of the actuator were altered. The performance of each ECLIPSE actuator was compared. The maximum achievable displacement of each actuator was measured by cyclically applying an electric field at low frequency between zero and the maximum electric field allowable for the piezoelectric material. The frequency was also increased to a resonance condition to characterize the fatigue behavior of these actuators. In addition, the force output of various actuators was measured with a four-point bending apparatus. The experimental data was compared to a classical lamination theory model and an extended classical lamination theory model. These models were used to predict actuator behavior as well as to calculate the stress and strain distribution through the thickness of the actuator.
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35

Al-Hazmi, M. W. A. "A study of distributed piezoelectric actuators for structural vibration control." Thesis, University of Salford, 2003. http://usir.salford.ac.uk/26518/.

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Interest in the use of smart-structure technology for noise and vibration reduction in helicopter applications has been on the rise in recent years. It has been established that significant gains in helicopter performance can be achieved through active rotor blade vibration control. This thesis presents a study of selective structural mode actuation of simple structures by means of surface-bonded piezoelectric actuator patches. The central objective of the study is to establish the potential for the use of piezoelectric actuators in active rotor blade vibration control applications. Theoretical and finite element vibration analyses were carried out, first for a thin flat plate and then for a long, straight, isotropic cantilever box beam. Finally a finite element vibration analysis was carried out for a three-cell hollow helicopter rotor blade structure. In each case, harmonic excitation of the structure by surface-bonded piezoelectric actuator patches is investigated, with the actuator patches in single and multiple configurations. The theoretical models are based on classical elasto-mechanics theory, and include the effect of bonding layer thickness. The finite element analyses were carried out with ANSYS 5.5. All analyses assume the use of readily available PZT4 ceramic piezoelectric actuator patches. The results lead to identification of optimal actuator patch configurations for selective mode excitation of the plate, box beam and helicopter rotor blade structures. Furthermore, the results for the box beam and rotor blade structures indicate that significant attenuation of the first two flapping modes and first two lagging modes can be achieved with practical levels of actuator excitation voltage. However, the results for selective excitation of the twist modes of the structures are inconclusive.
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36

Wang, Xiaodong. "The dynamic behaviour of interacting piezoelectric actuators in smart structures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ35363.pdf.

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37

Levinson, Jacob A. "Design and control of a robotic thumb using piezoelectric actuators." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54514.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 38).
Although much more complex and maneuverable than their predecessors, today's anthropomorphic robotic hands still cannot match the dexterity of human hands. While most of these limitations are caused by inadequate sensor and control systems, the use of large, heavy, and stiff actuators can also contribute to dexterity problems. If we expect robotic hands to interact with humans and human objects, joint actuators must allow a compromise of strength and compliance. Piezoelectric (PZT) actuators exhibit a high back driveability which could facilitate this compromise. Although they have low displacement and force output, they are useful in fine control applications. When combined with a DC motor, PZT actuators can produce precise, delicate movements in robotic hands. To develop the novel DC-PZT hybrid system, the force and displacement capabilities of PZT actuators were first characterized with a simple one degree of freedom system. The data from this characterization was analyzed and used to develop a one degree of freedom thumb using a hybrid DC motor/PZT actuator system. To study system performance, a simple position control scheme was implemented for the DC motor and PZT actuators. The experimental results suggest that current PZT actuators, even when combined with a DC motor, cannot produce enough thumb tip force to mirror the functionality of the human hand. That said, improvements to the actuator could make PZT-actuated hands a future possibility.
by Jacob A. Levinson.
S.B.
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38

Xie, Xiaoyue S. B. Massachusetts Institute of Technology. "Modified Maxwell Model for hysteresis compensation of piezoelectric stack actuators." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98747.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 29).
This thesis presents new observations of the hysteresis behavior of piezoelectric stack actuators and proposes an Input-Range Dependent Maxwell Model for more accurate hysteresis compensation. Experimental studies show that the assumptions of the classical Maxwell model do not fully hold: the actuator behaves differently in the initiation stage compared to the later cycles, and the parameters of the Maxwell model are dependent on the input history. Two most prominent factors are the input range of the most recent half loop and the local extremum input at the beginning of the current half loop. To accommodate for these variations, two types of modified Maxwell model are presented: the Input-Range Dependent Maxwell Model and the Local-Extremum Dependent Maxwell Model. We further propose parameter estimation schemes for each modified model. In both models, one set of parameters is obtained for the initiation stage and another set for later cycles, and the first Maxwell spring constant is related to the input history - input range or local extremum, respectively. Further studies suggested that the linear dependence of the first spring constant on the input range is much stronger than on the local extremum. Simulations with the identified Input-Range Dependent Maxwell Model gave a maximum percentage error of 2.71%, as compared with a percentage error of 8.29% using the classical Maxwell model. This suggests that the model can accurately predict the response of a piezoelectric stack actuator and is promising for hysteresis compensation in nano-positioning applications.
by Xiaoyue Xie.
S.B.
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39

Savran, Cagri Abdullah 1976. "Broadband active structural control using collocated piezoelectric sensors and actuators." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/89278.

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40

Peñalver-Àguila, Lluís Enric. "Piezoelectric buckling actuators : form reduction, bidirectional control, and optimal switching." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92131.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 101-102).
Piezoelectric stack actuators are generally described as having large force density, high bandwidth response, and limited yet precise displacement properties. As a result, these actuators have been widely applied to precision positioning devices, acoustical and optical instruments, and within vibration control mechanisms. Techniques to efficiently amplify this limited displacement have been central to recent piezo-actuator research. One such technique exploits structural buckling to achieve displacement amplification gains greater than 100 while limiting energy transmission loss into the amplifying mechanism. This thesis first surveys the recently developed piezoelectric buckling actuator and identifies critical design elements that may be further optimized to reduce the mechanism's form factor. Focus is directed towards simultaneously reducing structural compliance and mass in the actuator's frame and rotational joints. Use of carbon fiber and new geometry improves structural efficiency while increased joint stiffness is shown through design and material changes. Discussion then shifts to the nondeterministic output of a standalone buckling actuator and methods to address it. A design is presented which couples the buckling actuator to an energy storing mechanism that alternates output direction by enforcing hysteretic force-displacement behavior using a closed loop cam-follower path. Finally, a dual buckling actuator mechanism is discussed which exhibits both quasi-static and dynamic motion properties through asynchronous activation control. Through the use of phase-plane analysis, an optimal switching control law is described. Prototypes of single and dual buckling actuator mechanisms are shown, and experimental performance is presented.
by Lluís Enric Peñalver-Àguila.
S.M.
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41

Evans, Joshua L. "SMALL SATELLITE NONCOMMUTATIVE ROTATION SEQUENCE ATTITUDE CONTROL USING PIEZOELECTRIC ACTUATORS." UKnowledge, 2016. http://uknowledge.uky.edu/ece_etds/91.

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Attitude control remains one of the top engineering challenges faced by small satellite mission planning and design. Conventional methods for attitude control include propulsion, reaction wheels, magnetic torque coils, and passive stabilization mechanisms, such as permanent magnets that align with planetary magnetic fields. Drawbacks of these conventional attitude control methods for small satellites include size, power consumption, dependence on external magnetic fields, and lack of full control authority. This research investigates an alternative, novel approach to attitude-control method for small satellites, utilizing the noncommutative property of rigid body rotation sequences. Piezoelectric bimorph actuators are used to induce sinusoidal small-amplitude satellite oscillations on two of the satellites axes. While zero net change occurs on these signaled axes, the third axis can develop an average angular rate. This noncommutative attitude control methodology has several advantages over conventional methods, including scalability, power consumption, and operation outside of Earth's magnetic field. This research looks into the feasibility of such a system, and lays the foundation for a simple control system architecture.
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42

Niezrecki, Christopher. "Power factor correction and power consumption characterization of piezoelectric actuators." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/42619.

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A piezoceramic actuator used for structural control behaves electrically as a nearly pure capacitance. When conventional amplifiers are used to drive these actuators, the current and voltage is close to 90 degrees out of phase. This causes the power factor (PF) of the load to be close to zero and results in excessive power requirements. This thesis reports the results of a study of the following question: What effect does applying power factor correction methods to piezoceramic actuators have on their power consumption characteristics? A subproblem we explored was to detennine the qualitative relationship between the power consumption of a piezoceramic actuator and the damping that actuator added to a structure. To address the subproblem, a feedback control experiment was built which used a ceramic piezoceramic actuator and a strain rate sensor configured to add damping to a cantilevered beam. A disturbance was provided by a shaker attached to the beam. The power consumption of the actuator was detennined by measuring the current and voltage of the signal to the actuator. The energy dissipated in the beam by the feedback control loop was assumed to be modeled by an ideal structural damping model. A model relating structural damping as a function of the apparent power consumed by the actuator was developed, qualitatively verified, and physically justified. Power factor correction methods were employed by adding an inductor in both parallel to and in series with the piezoceramic actuator. The inductance values were chosen such that each inductor-capacitor (LC) circuit was in resonance at the second natural frequency of the beam. Implementing the parallel LC circuit reduced the current consumption of the piezoceramic actuator by 75% when compared to the current consumption of the actuator used without an inductor. Implementing the series LC circuit produced a 300% increase in the voltage applied to the actuator compared to the case when no inductor was used. In both cases, employing power factor correction methods corrected the power factor to near unity and reduced the apparent power by 12 dB. A theoretical model of each circuit was developed. The analytical and empirical results are virtually identical. The results of this study can be used to synthesize circuits to modify piezoceramic actuators, reducing the voltage or current requirements of the amplifiers used to drive those actuators
Master of Science
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43

Richard, John S. "Modeling of multiple layered piezoelectric actuators in active structural control." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12052009-020234/.

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44

Bolzmacher, Christian [Verfasser]. "Miniaturized Piezoelectric Actuators for High-Speed Flow Control Applications / Christian Bolzmacher." Aachen : Shaker, 2011. http://d-nb.info/1098039440/34.

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45

Koike, Ayako. "Torsional and flexural control of sandwich composite beams with piezoelectric actuators." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06232009-063235/.

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46

Béchet, Antoine. "Ultrasonic detection of debonding within a gradient enhanced piezoelectric actuator (GEPAC)." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/17914.

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47

Diehl, Gregory W. "The effects of shaped piezoceramic actuators on the excitation of beams." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09292009-020202/.

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48

Obal, Michael Walter. "Vibration control of flexible structures using piezoelectric devices as sensors and actuators." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/12025.

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49

Won, Chin Chung. "Active control of smart structure : theory and experiment." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/12374.

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50

El, Rifai Osamah M., and Kamal Youcef-Toumi. "Modeling of Piezoelectric Tube Actuators." 2003. http://hdl.handle.net/1721.1/3911.

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A new dynamic model is presented for piezoelectric tube actuators commonly used in high-precision instruments. The model captures coupling between motions in all three axes such as bending motion due to a supposedly pure extension of the actuator. Both hysteresis and creep phenomena are included in the overall actuator model permitting modeling nonlinear sensitivity in the voltage to displacement response. Experimental data on hysteresis and creep are presented to support the modeling. Experiments and model predictions show that due to coupling a voltage Vz corresponding to vertical displacement will produce lateral displacement that acts as a disturbance to the main lateral response. The resonance frequency for the lateral dynamics is inherently lower than that of the longitudinal dynamics. Therefore, Vz is expected to contain frequencies that may excite the lateral resonance. Accordingly, this out of bandwidth disturbance will not be well compensated for either in open or closed loop control of the actuator. In order to preserve performance in open loop actuator control and stability and performance in closed loop control, a large reduction in the bandwidth of vertical motion would be required to avoid exciting the first bending mode.
Singapore-MIT Alliance (SMA)
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