Tesi sul tema "Piezoelectric actuator"
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1
Giurgea, Constantin. "Precise motion with piezoelectric actuator". Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6184.
Testo completoAbstract (sommario):
The purpose of this study is to determine the displacement performance of a high accuracy-positioning device equipped with three piezo ceramic actuators. The displacement performance of each individual actuator is investigated in order to perform controlled motion over a very small range. A nanometric precision three-degrees of freedom positioner was designed and fabricated. In order to design a proper closed-loop controller, the open loop characteristics of the nanopositioner were experimentally investigated.
2
Qiu, Yan. "Distributed piezoelectric actuator with complex shape". Thesis, Peninsula Technikon, 2002. http://hdl.handle.net/20.500.11838/1263.
Testo completoAbstract (sommario):
Thesis (MTech (Mechanical Engineering))--Peninsula Technikon, Cape Town, 2002Distributed 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.
3
Henslee, Isaac Andrew. "Macrofiber piezoelectric composite for lunar exploration actuator". Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/henslee/HensleeI0810.pdf.
Testo completoAbstract (sommario):
Understanding the nature and location of water and other resources on Earth's Moon is an essential component to the National Aeronautics and Space Administration's (NASA) space exploration efforts. To aid in these exploration efforts, an investigation into lightweight and reliable materials for a lunar valve actuator design has lead to characterizing the lifetime performance of the piezoelectric fiber composite, macro fiber composite (MFC). MFC's are thin rectangular patches made of polyimide film, epoxy and a single layer of rectangular lead zirconium titanate fibers and are commercially available. As a basis for this consideration, the useful life of the MFC is being characterized to determine the effect of temperature on the performance of the material as it is fatigued by cyclical piezoelectric excitation or actuation. The test specimen consist of the MFC laminated to a cantilevered stainless steel beam using epoxy and is actuated at the first resonant frequency of the beam laminate by the cyclic application of 1000 volts. Strain and beam tip displacement measurements are used as a basis for determining the performance of the MFC as it is cyclically actuated under various operating temperatures. The temperature of the beam laminate is held constant during cyclic actuation and cycled to failure or 250 million cycles, to determine the useful life of the MFC over a temperature range from -15°C to 145°C. The results of the experimentation efforts show a strong temperature dependence on operational life for the MFC. No significant degradation in operational performance was identified thru monitoring of the MFC, as the MFC was cyclically actuated up to the point of failure, regardless of temperature or actuation cycle. The results of the experimental testing can be used to better inform designs, such as actuators, using MFC in environments where operational temperatures differ from standard laboratory temperatures, as well as, to better design temperature controlled environments where MFC's are used as actuators.
4
Fu, Bo. "Piezoelectric actuator design via multiobjective optimization methods". kostenfrei, 2005. http://ubdata.uni-paderborn.de/ediss/10/2005/fu/.
Testo completo
5
deSa, Johann Lec Ryszard. "Manipulation of microparticles using a piezoelectric actuator /". Philadelphia, Pa. : Drexel University, 2009. http://hdl.handle.net/1860/3197.
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6
Tuncdemir, Safakcan. "Design Of Mini Swimming Robot Using Piezoelectric Actuator". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605682/index.pdf.
Testo completoAbstract (sommario):
This thesis deals with the design, fabrication and analysis of a novel actuator for a fish-like swimming mini robot. The developed actuator is tested on a mini boat. The
actuator relies on a novel piezoelectric ultrasonic motor, developed according to the design requirements of actuator for fish-like swimming mini robots. Developed motor is within the dimensions of 25x6x6 mm in a simple mechanical structure with simple driving circuitry compared to its predecessor. Bidirectional rotation of the motor is transformed to a flapping tail motion for underwater locomotion in a simple mechatronic structure. The simplicity in the motor and actuator enables
further development on the miniaturization, improvement on the performances as well as easy and low cost manufacturing. The developed actuator is a candidate to
be used in mini swimming robot with fish- like locomotion.
7
Holmes, J. E. "Novel piezoelectric structures for sensor and actuator applications". Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399477.
Testo completo
8
Hu, Zhaoli. "Analyses and application of piezoelectric actuator in decoupled vibratory feeding". Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1131113775.
Testo completo
9
Vinge, Even. "Nanopositioning : Construction and Analysis of a Piezoelectric Tube Actuator". Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9866.
Testo completoAbstract (sommario):
Piezoelectric tubes are commonly used as scanning actuators in nano precision microscopes. They can achieve precision down to sub-nanometer scale, but their vibrational dynamics and nonlinear properties hamper their ability to achieve higher bandwidths. In order to deal with this, further research is needed. This thesis is a first look into the field of piezoelectric tube actuators, intended to lay the groundwork for further research on the subject at NTNU. It details the construction of a laboratory setup for actuation and nanometer displacement measurement of a piezoelectric tube. Needed specifications are found and a mechanical setup is designed. Basic theory on piezoelectricity is presented, along with the setup and equipment used for the thesis. Several experiments are designed and conducted in order to identify the linear dynamics and nonlinear properties of the piezoelectric tube. The results are discussed and related to current literature. This includes the linear frequency responses from applied voltage to displacement of the piezoelectric tube, noise levels and nonlinear properties such as displacement creep and hysteresis. Generally, the results are found to closely match what has been found in similar research, although there are some notable differences, such as a somewhat smaller low frequency gain and a much lower resonant peak frequency of the system. Several possible explanations for these disparities are discussed. Both a capacitive sensor and a piezoelectric strain voltage sensor are utilized for measuring displacement. It is found that the capacitive sensor has a higher noise level but is more accurate at lower frequencies than the strain voltage sensor. The two measurements are then combined into an improved estimate of the displacement of the piezoelectric tube.
10
Ring, Emma. "Modelling a piezoelectric-driven actuator for active flow control". Thesis, Linköpings universitet, Reglerteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-114957.
Testo completoAbstract (sommario):
Flow control is an area of research of particular interest within automotive and aerospace industries since methods used to affect the fluid flow around vehicles can reduce drag and therefore lower their fuel consumption. One of these methods, which has generated a lot of interest in later years, is called active flow control and uses different types of actuators to impact the surrounding flow. In this thesis a model of a piezoelectric actuator for active flow control has been developed using Lumped Element Modelling and equivalent circuits. This approach, together with the chosen software for implementation, Simulink, provides models which are easy to simulate and evaluate. The actuator model has been validated using a novel methodology with sub-models with the purpose of reducing computational costs. The actuator is therefore divided into two submodels,one for structural and one for fluid dynamics, which are validated separately. This enables the use of simple yet accurate FEM and CFD models instead of time consuming FSI software which the complete model requires. The three implemented models have been validated using cases presented in previous studies and data from CFD-simulations. The results show that the decoupled models can be validated separately and its results can be integrated into the complete model, although further tests with a real actuator is needed. In addition to the modelling, a parameter study of the actuator has been performed in order to prepare for prototype design.
11
Chi, Zi Qiang. "Fuzzy feedback control of piezoelectric actuator with feedforward compensation". Thesis, University of Macau, 2015. http://umaclib3.umac.mo/record=b3335773.
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12
Davis, Brandon Witt. "Constitutive behavior and reliability of actuator materials". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/17856.
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13
Ha, Kwangtae. "A Combined Piezoelectric Composite Actuator and Its Application to Wing/Blade Tips". Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7575.
Testo completoAbstract (sommario):
A novel combined piezoelectric-composite actuator configuration is proposed and analytically modeled in this work. The actuator is a low complexity, active compliant mechanism obtained by coupling a modified star cross sectional configuration composite beam with a helicoidal bimorph piezoelectric actuator coiled around it. This novel actuator is a good candidate as a hinge tension-torsion bar actuator for a helicopter rotor blade flap or blade tip and mirror rotational positioning. In the wing tip case, the tip deflection angle is different only according to the aerodynamic moment depending on the hinge position of the actuator along the chord and applied voltage because there is no centrifugal force. For an active blade tip subject to incompressible flow and 2D quasi steady airloads, its twist angle is related not only to aerodynamic moment and applied voltage but also to coupling terms, such as the trapeze effect and the tennis racquet effect. Results show the benefit of hinge position aft of the aerodynamic center, such that the blade tip response is amplified by airloads. Contrary to this effect, results also show that the centrifugal effects and inertial effect cause an amplitude reduction in the response. Summation of these effects determines the overall blade tip response. The results for a certain hinge position of Xh=1.5% chord aft of the quarter chord point proves that the tip deflection target design range[-2,+2] can be achieved for all pitch angle configurations chosen.
14
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.
Testo completoAbstract (sommario):
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).
15
Juuti, J. (Jari). "Pre-stressed piezoelectric actuator for micro and fine mechanical applications". Doctoral thesis, University of Oulu, 2006. http://urn.fi/urn:isbn:9514279891.
Testo completoAbstract (sommario):
Abstract
In this thesis pre-stressed piezoelectric actuators for micro and fine mechanical applications have been developed. First, RAINBOW (Reduced And INternally Biased Oxide Wafer) and thick film actuators were manufactured and their electromechanical properties were characterised. In the second part, the novel pre-stressed piezoelectric actuator PRESTO (PRE-STressed electrOactive component by using a post-fired biasing layer) was developed and its electrical and electromechanical properties were measured.
Commercial piezoelectric PZT 5A and PZT 5H discs were used in the RAINBOW and PRESTO actuators and PLZT paste for thick film actuators. The pre-stressing of the PRESTO actuators was based on the sintering shrinkage and different thermal expansion coefficient of the piezoelectric disc and passive material. Dielectric LTCC tape and AgPd paste were utilized as pre-stressing media and passive layer by using lamination and screen-printing, respectively. Different active and passive layer thicknesses and electrode materials were realized in order to obtain high displacements and good load bearing capability for actuators.
The PRESTO actuators showed a significantly higher coercive electric field than their bulk counterparts, but a decreased remanent polarisation. The displacement as a function of load was measured under 0.3–3 N loads and electric fields up to ±0.75 MV/m. The highest displacement of 118 μm was obtained with a 250 μm thick PZT 5H actuator (Ø 25 mm) with LTCC tape (thickness ~96 μm) as the pre-stressing material. The corresponding actuator with AgPd pre-stressing material (thickness ~33 μm) produced 63 μm displacement. Additionally, PRESTO actuators were tested with a glued steel layer in a mechanical amplifier which obtained displacements up to 1.2 mm.
Effective d31 coefficients of the PRESTO actuators were derived using an analysis based on unimorph model and measured displacement data. The actuators exhibited significantly enhanced effective d31 coefficients (d31eff = -690 pm/V and d31eff = -994 pm/V for PZT 5A and 5H, respectively) comparable to the RAINBOW actuators. Mass-producible PRESTO actuators with high displacement, moderate load bearing capabilities and integration possibilities can be utilised in various micro and fine mechanical devices e.g. dosing devices, electromechanical locks, regulators, positioners vibrators, speakers, adjusters, pumps, valves, relays, dispensers, micromanipulators, etc.
16
Tzianetopoulou, Theodora 1974. "Design of an improved piezoelectric actuator for helicopter rotor control". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/82197.
Testo completo
17
Nickless, Benjamin John. "Dynamic modeling and position control of a piezoelectric flextensional actuator". College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8970.
Testo completoAbstract (sommario):
Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Aerospace Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
18
Mehta, Parikshit. "Vibrations of thin plate with piezoelectric actuator theory and experiments /". Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1263400450/.
Testo completo
19
Mtawa, Alexander Nikwanduka. "Influence of geometry and material properties on the optimum performance of the C-shape piezo-composite actuator". Thesis, Cape Peninsula University of Technology, 2008. http://hdl.handle.net/20.500.11838/1301.
Testo completoAbstract (sommario):
Thesis (DTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2008In recent years, due to rapid advances in technology there has been an increasingly high demand for large displacement and large force, precise positioning, fast response, low power consuming miniature piezoelectric actuators. In certain smart structure applications, the use of curved piezoelectric actuators is necessary. The present work extends the earlier investigations on the C- shape actuator by providing a detailed investigation on the influence of geometric and material properties of the individual layers of the C-shape piezocomposite for its optimal performance as an actuator. Analytical models have. been used to optimize the geometry of the actuator. Experimental and finite element analyses (using general purpose finite element software i.e. CoventerWare and MSC. Marc) have been used for validation. The present work has established that, by maintaining the thickness of the substrate and piezoceramic layers constant; changing the external radius, for example increasing it, the stiffness of the structure decreases and thus yielding large displacement This has a negative effect on the force produced by the actuator. With fixed thickness of the substrate and varying the thickness of the piezoceramic (for fixed external radius) the result is as follows: Increasing the thickness of the piezoceramic layer has the effect of decreasing the displacement while the force increases. With fixed PZT thickness as well as the external radius, varying the substrate thickness has the following effect: As the thickness of the substrate increases the displacement increases reaching a maximum. Subsequent increase in the thickness of the substrate the displacement is reduced. The force continues increasing at least for the ratios up to 1.0, further increase of the substrate, subsequent decrease of force is also noted. In addition to changing the thickness of the substrate, the choice of different material for the substrate has the following effect: For substrate/PZT ratios of up to 0.6. an actuator with substrate material having higher elastic modulus will produce larger displacement while for ratios beyond this ratio the situation is reversed. The causes for this kind of behaviour have been addressed. In all cases both force and displacement are found to be directly proportional to applied voltage.
20
Bhargava, Adesh. "Experimental/analytical determination of optimal piezoelectric actuator locations on complex structures based on the actuator power factor". Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-08222009-040530/.
Testo completo
21
Sharp, Scott L. "Design of a Linear Ultrasonic Piezoelectric Motor". BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/997.
Testo completoAbstract (sommario):
A new geometrically unique ultrasonic motor (USM) was designed using finite element modeling (FEM). A USM operates by vibrating a drive tip in an elliptical motion while it is in periodic contact with a driven surface. Piezoelectric elements are used to create the elliptical motions and are driven near a resonant frequency to create the needed displacements for the motor to operate. An idea for a motor frame was conceived that consisted of an arch, a center ground, and two piezoelectric elements connected to the center ground. End caps were added between the frame and the piezoelectric elements to reduce the stress of the elements. Legs located at the bottom of were used to increase the rigidity. Several FEM programs were written to design the motor and to predict its performance. The FEM motor model exceeded the performance characteristics of the benchmark Nanomotion HR1. The model predicted a linear motor capable of pushing up to 5 N and a maximum speed of 0.4 m/s. A prototype frame was built out of tool steel and run against an oxide ceramic plate. The USM prototype's piezoelectric elements did not provide the expected displacements in the motor frame as determined by the FEM. The discrepancy was determined to be caused manufacturing errors. Soft glue layers were thicker than expected on each side of the piezoelectric elements causing a large amount of compliance inline with the piezoelectric motion. An additional unexpected layer of glue between the end cap and frame increased the compliance inline with the piezoelectric elements even more. It was also determined that even if the motor had been assembled properly that Hertzian displacement would have caused a 1/3 decrease in piezoelectric motion. The prototype frame's steady state displacements were approximately 20% of the expected output from the FEM models. The motor was still able to achieve a maximum speed of 55.6 mm/s and a push force of 0.348 N at a preload of 6 N. It is expected that a motor assembly correctly dimensioned and manufactured and designed to minimize Hertzian displacement would result in a significantly better performing prototype.
22
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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23
Mali, Girish Suresh. "Novel Escapement Mechanism using a Compliant Mechanism and a Piezoelectric Actuator". Digital WPI, 2007. https://digitalcommons.wpi.edu/etd-theses/1110.
Testo completoAbstract (sommario):
"Escapement mechanisms hold back a stream of parts driven either by mechanical or pneumatic means for a length of time and release a single part as required to an assembly station. They are used in most automatic multi-component assembly equipment. They occupy a significant design space and have dynamic characteristics of their own. This research aimed to develop a novel high speed mechanism for parts escapement that occupies less design space and contributes less to the dynamic activity of the structure. Several conceptual mechanisms were generated and evaluated. A compliant mechanism that amplifies the very small displacement of a piezo actuator was selected for detailed design. A proof of concept prototype was fabricated and tested. A piezo stack was used to bend a thin, spring steel, compliant beam. Its deflection was further amplified by attaching a comparatively rigid beam extension at the end of the compliant section. The mechanism escapes parts at 16 Hz using constrained layer damping on the beam to reduce vibrations. The concept is feasible to use on production machinery and provides advantages in terms of higher operating speeds and compactness. The concept could also be used where there is a requirement of high speed gating."
24
Torres, James Ph D. Massachusetts Institute of Technology. "Harmonic poly-actuator : design and control of a new piezoelectric mechanism". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101538.
Testo completoAbstract (sommario):
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 127-132).
Piezoelectric devices, e.g. piezoelectric stack actuators, have several salient features inherent to their structure. They are efficient, have a high bandwidth, and their capacitive loading allows for static loads to be maintained with virtually no power consumption. The major preventative drawback that limits more widespread use is the small strain, on the order of 0.1%. For marco-scale applications, the displacement must be amplified, typically through mechanical or frequency leveraging. Both have inherent limitations: mechanical devices can increase the stroke but is naturally limited; and frequency devices relies on friction and is limited to nanopositioning. In this thesis, we investigate combining a unique mechanical amplification with a frequency amplification device that does not rely on friction to produce an arbitrarily large stroke linear actuator. The first stage of amplification aims to achieve the greatest displacement amplification without sacrificing force capabilities. The second stage relies on the coordinated actuation of multiple copies of the mechanically amplified device to produce a long stroke, smooth force poly-actuator. The theoretical design concepts for each stage of amplification are explicitly derived. The mechanical amplification device uses rolling contact joints to maintain stiff connections to transmit the force without losses due to friction; and the frequency amplification uses a sinusoidal Transmission interface to exploit a passive balancing of undesirable non-linearities, proven by harmonic analysis. A unique control algorithm is developed to produce a wide variety of capabilities. The theoretical findings are supported by experimental prototypes. The mechanical amplification device produces a comparable energy density while amplifying the displacement by an additional factor 10. The proof-of-concept poly-actuator prototype can continually produce +/-100 Newtons of force over a stroke of 200 mm. We conclude with simulations, which are verified through physical experiments, used to estimate several performance metrics for comparison.
by James Torres.
Ph. D.
25
Prechtl, Eric Frederick. "Development of a piezoelectric servo-flap actuator fro helicopter rotor control". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/11731.
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Oliveira, Éder Luiz. "Application of piezoelectric materials as sensor and actuator for aeroelastic investigation". Instituto Tecnológico de Aeronáutica, 2014. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=3038.
Testo completoAbstract (sommario):
This dissertation aims to apply piezoelectric materials as actuator and sensor to perform aeroelastic analysis. Two semi-span wing models based on flat plates with different characteristics were tested using PZT (Lead Zirconate Titanate) as actuator, PVDF (Polyvinylidene Fluoride) as sensor and the results were compared with vibrometer laser results. An aluminum model with a ballast on the wing tip, whose its location can be modified was tested in experimental modal analysis. Using the aluninum model, an investigation about aeroelastic behaviour was conducted in wind tunnel and the V-g/V-f diagram determined. This diagram shows the aeroelastic evolution of the natural frequencies and damping as function of speed (or dynamic pressure). In this aeroelastic analysis, the ability of the PVDF in determining the V-g/V-f diagram was evaluated. A numerical model of composite flat plate was generated considering the piezoelectric instrumentations. The second specimen tested corresponds to composite wing models that are based on laminate composite flat plate. Five models with different fiber orientations were tested in (pure) experimental modal analyses and wind tunnel, hence, the capability of excitation of PZT was verified. Good results were obtained regarding the estimation of natural frequency and damping factor using a single PVDF element. The application of PZT as actuator in the wind tunnel test showed improvement on the data acquisition in terms of noise. However, were observed some characteristics that require careful. As support to experimental tests, several studies were performed.
27
Jia, Jianhu. "Optimization of piezoelectric actuator systems for vibration control of flexible structures". Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39754.
Testo completoAbstract (sommario):
Actuator placement is a major concern in control system designs. Utilizing piezoelectric actuators increases the complexity of actuator designs, because both actuator location and dimensions need to be considered. A comprehensive study was conducted in this dissertation on the optimization of piezoelectric actuator designs for vibration suppression of flexible structures.
The investigation on the optimal piezoelectric actuator designs were grouped into two parts. Part one covered actuator designs when the same number of actuators as the controlled modes are used. Approaches were formed to optimally design piezoelectric actuators which requires least control efforts.
In part two of this dissertation, a method named the Weighted Pseudoinverse Method was introduced to deal with the cases in which fewer actuators than the controlled modes are utilized. The weighted pseudoinverse method yields a optimal transformation from modal control forces into the actuator-moments in physical space. Based on the Weighted pseudoinverse method, the piezoelectric actuator designs were optimized to ensure least-control-effort actuator designs. A simply-supported beam was used as an example to demonstrate the effectiveness of the design methods proposed in this dissertation. However, the design methods are applicable to general cases.Ph. D.
28
Stander, Cornelius Johannes. "The passive control of machine tool vibration with a piezoelectric actuator". Diss., University of Pretoria, 2000. http://hdl.handle.net/2263/23038.
Testo completoAbstract (sommario):
Please read the abstract in the section 00front of this documentDissertation (M Eng (Mechanical Engineering))--University of Pretoria, 2000.
Mechanical and Aeronautical Engineering
unrestricted
29
Wilhelms, John, e Marcus Trulsson. "Open Loop Control of Piezoelectric Cantilever Speaker". Thesis, Linköpings universitet, Reglerteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122363.
Testo completoAbstract (sommario):
Actuating a cantilever piezoelectric element over a frequency spectrum, the movement will show resonances and hysteresis behavior not present in the input signal. Excursion modeling and open loop control of a cantilever piezoelectric bimorph actuator was studied in this thesis, with the aim to enhance the actuator's movement to more accurately render audible input. This actuator has lower energy consumption and presents new possibilities for speaker design in constrained situations compared to conventional micro speaker technology. Much work has previously been done to model piezoelectric cantilever actuators below the first and second resonance frequency. This thesis describes a physical linear model and its modifications to render the eight first resonance frequencies below 20 kHz, as well as the model's performance in open loop control. This was performed on a single piezoelectric beam and a concept piezoelectric speaker. For the single piezoelectric beam the model was validated with fair overall result below 3 kHz. The model is suggested to have fair overall behavior up to 15 kHz. Above 15 kHz the experiments showed changed characteristics that were not modeled well. The open loop control had the intended behavior but severe resonances and physical constraints made the open loop control ineffective to enhance the sound rendering. Two different approaches were used for trying to improve the sound rendering based on an excursion model. These approaches did not generate useful methods but present viable input to future work with this type of speaker structure, for reducing disharmonics and creating a physical design tool for sound simulation. For the concept piezoelectric speaker, due to difficulties in measuring excursion, the model could not be validated. This made the approaches for enhancing the sound rendering ineffective. However, it can be concluded from the concept speaker that the cantilever piezoelectric speaker technology has qualities that could compete with the conventional micro speaker technology. Challenges remain in electric hardware, actuator configuration and acoustic design as well as in fine tuned signal processing for the concept speaker to become a competitive product.
30
Gex, Dominique. "Ultrasonic NDE testing of a gradient enhanced piezoelectric actuator (GEPAC) undergoing low frequency bending excitation". Thesis, Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04062004-171807/unrestricted/gex%5Fdominique%5Fc%5F200405%5Fmast.pdf.
Testo completoAbstract (sommario):
Thesis (M.S.)--Mechanical Engineering, Georgia Institute of Technology, 2004.Berthelot, Committee Chair; Lynch, Committee Member; Jacobs, Committee Member. Includes bibliographical references (leaves 111-113).
31
Wu, Ze Yi. "Design and implementation of compact micro- nano-positioning stage driven by piezoelectric actuator". Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3950618.
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Smith, Byron Fitzgerald. "Development and Characterization of a Mechanically Prestressed Piezoelectric Composite". VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/869.
Testo completoAbstract (sommario):
Piezoelectric composites have been investigated for use in a variety of areas, including flow control, structural control, energy harvesting, and fuel ignition systems. While many of the investigations conducted in these areas have utilized traditional piezo actuation systems, such as unimorphs or stack actuators, a growing number of research groups are examining the increased performance derived from the mechanical advantage, and enhanced domain rotation, found in prestressed unimorph designs. Prestressed devices, like Thunder® and LIPCA, have been shown well suited for a number of applications; however, the price associated with these devices can often prevent them from being implemented. In an effort to produce a low cost unimorph device that possesses a performance-enhancing curved form, the present investigation presents a novel technique for manufacturing prestressed piezoelectric actuators that are capable of meeting the same high displacement and load bearing capabilities exhibited by conventional prestressed devices. The newly proposed mechanically prestressed composite device, or MPC, is similar in form and function to well-documented thermally prestressed devices like Thunder®. However, rather than deriving its characteristic curved form from a thermally induced stress, the present class of devices relies on the resorting force incited in the piezoelectric ceramic upon adhesion to a mechanically deformed substrate to provide both the performance-enhancing prestress and final form of the device. To aid in refinement of the newly proposed design, beam theory was used to model the stress developed within the device. The model allowed designers to investigate the limitations imposed on the performance-enhancing curved form of the device by the stresses developed in the ceramic as a result of the curvature. Findings derived from the model were experimentally verified before a finalized design was specified for the composite, and a number of devices were manufactured. An initial characterization of the device was carried out based on the composite's response to mechanical and electrical loading. By determining the slope of the electrically and mechanically induced displacement response of the device, the investigation was able to define the center displacement constant and effective spring constant of the unimorph. These parameters not only allow designers to predict the displacement that will occur in response to a given electric field or tensile load, but also to allow for comparison with various devices. In the present investigation, the performance characteristics of mechanically prestressed composites were assessed as a function of substrate thicknesses and adhesive properties. With composites constructed using substrates approximately 9.2cm in length, devices were found to have typical center displacement constants on the order of 1.59 to 7.78kV/mm2 while retaining an effective stiffness between 4.5 to 7.5N/mm. These values were found to be similar to the .71 to 3.85kV/mm2 center displacement constants demonstrated by similarly sized and shaped Thunder® devices, which posses an effective stiffness in the range of 10 to 16.3N/mm. A comprehensive presentation of the test methods and procedures used to determine these values, along with other performance characteristics, are provided.
33
Nguyen, Van Ky Quan. "PIEZOELECTRIC ACTUATOR DESIGN OPTIMISATION FOR SHAPE CONTROL OF SMART COMPOSITE PLATE STRUCTURES". University of Sydney. Aerospace, Mechanical and Mechatronic, 2005. http://hdl.handle.net/2123/652.
Testo completoAbstract (sommario):
Shape control of a structure with distributed piezoelectric actuators can be achieved through optimally selecting the loci, shapes and sizes of the piezoelectric actuators and choosing the electric fields applied to the actuators. Shape control can be categorised as either static or dynamic shape control. Whether it is a transient or gradual change, static or dynamic shape control, both aim to determine the loci, sizes, and shapes of piezoelectric actuators, and the applied voltages such that a desired structural shape is achieved effectively. This thesis is primarily concerned with establishing a finite element formulation for the general smart laminated composite plate structure, which is capable to analyse static and dynamic deformation using non-rectangular elements. The mechanical deformation of the smart composite plate is modelled using a third order plate theory, while the electric field is simulated based on a layer-wise theory. The finite element formulation for static and dynamics analysis is verified by comparing with available numerical results. Selected experiments have also been conducted to measure structural deformation and the experimental results are used to correlate with those of the finite element formulation for static analysis. In addition, the Linear Least Square (LLS) method is employed to study the effect of different piezoelectric actuator patch pattern on the results of error function, which is the least square error between the calculated and desired structural shapes in static structural shape control. The second issue of this thesis deals with piezoelectric actuator design optimisation (PADO) for quasi-static shape control by finding the applied voltage and the configuration of piezoelectric actuator patch to minimise error function, whereas the piezoelectric actuator configuration is defined based on the optimisation technique of altering nodal coordinates (size/shape optimisation) or eliminating inefficient elements in a structural mesh (topology optimisation). Several shape control algorithms are developed to improve the structural shape control by reducing the error function. Further development of the GA-based voltage and piezoelectric actuator design optimisation method includes the constraint handling, where the error function can be optimised subjected to energy consumption or other way around. The numerical examples are presented in order to verify that the proposed algorithms are applicable to quasi-static shape control based on voltage and piezoelectric actuator design optimisation (PADO) in terms of minimising the error function. The third issue is to use the present finite element formulation for a modal shape control and for controlling resonant vibration of smart composite plate structures. The controlled resonant vibration formulation is developed. Modal analysis and LLS methods are also employed to optimise the applied voltage to piezoelectric actuators for achieving the modal shapes. The Newmark direct time integration method is used to study harmonic excitation of smart structures. Numerical results are presented to induce harmonic vibration of structure with controlled magnitude via adjusting the damping and to verify the controlled resonant vibration formulation.
34
Headings, Leon Mark. "Modeling, characterization, and design of smart material driven stick-slip actuation mechanisms". Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141700440.
Testo completo
35
Morrisette, Jennifer A. "The use of a piezoelectric actuator to improve precision of a coordinate measurement machine". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17044.
Testo completo
36
Ohka, Masahiro, Yasuhiro Sawamoto, Shiho Matsukawa, Tetsu Miyaoka e Yasunaga Mitsuya. "A Two-axis Bimorph Piezoelectric Actuator for Pressure and Slippage Force Presentation". IEEE, 2006. http://hdl.handle.net/2237/9501.
Testo completo
37
Zai, Marvin Ho-Ming. "Chemical synthesis of lead zirconate titanate thin films for a piezoelectric actuator". Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367760.
Testo completo
38
Nguyen, Van Ky Quan. "PIEZOELECTRIC ACTUATOR DESIGN OPTIMISATION FOR SHAPE CONTROL OF SMART COMPOSITE PLATE STRUCTURES". Thesis, The University of Sydney, 2005. http://hdl.handle.net/2123/652.
Testo completoAbstract (sommario):
Shape control of a structure with distributed piezoelectric actuators can be achieved through optimally selecting the loci, shapes and sizes of the piezoelectric actuators and choosing the electric fields applied to the actuators. Shape control can be categorised as either static or dynamic shape control. Whether it is a transient or gradual change, static or dynamic shape control, both aim to determine the loci, sizes, and shapes of piezoelectric actuators, and the applied voltages such that a desired structural shape is achieved effectively. This thesis is primarily concerned with establishing a finite element formulation for the general smart laminated composite plate structure, which is capable to analyse static and dynamic deformation using non-rectangular elements. The mechanical deformation of the smart composite plate is modelled using a third order plate theory, while the electric field is simulated based on a layer-wise theory. The finite element formulation for static and dynamics analysis is verified by comparing with available numerical results. Selected experiments have also been conducted to measure structural deformation and the experimental results are used to correlate with those of the finite element formulation for static analysis. In addition, the Linear Least Square (LLS) method is employed to study the effect of different piezoelectric actuator patch pattern on the results of error function, which is the least square error between the calculated and desired structural shapes in static structural shape control. The second issue of this thesis deals with piezoelectric actuator design optimisation (PADO) for quasi-static shape control by finding the applied voltage and the configuration of piezoelectric actuator patch to minimise error function, whereas the piezoelectric actuator configuration is defined based on the optimisation technique of altering nodal coordinates (size/shape optimisation) or eliminating inefficient elements in a structural mesh (topology optimisation). Several shape control algorithms are developed to improve the structural shape control by reducing the error function. Further development of the GA-based voltage and piezoelectric actuator design optimisation method includes the constraint handling, where the error function can be optimised subjected to energy consumption or other way around. The numerical examples are presented in order to verify that the proposed algorithms are applicable to quasi-static shape control based on voltage and piezoelectric actuator design optimisation (PADO) in terms of minimising the error function. The third issue is to use the present finite element formulation for a modal shape control and for controlling resonant vibration of smart composite plate structures. The controlled resonant vibration formulation is developed. Modal analysis and LLS methods are also employed to optimise the applied voltage to piezoelectric actuators for achieving the modal shapes. The Newmark direct time integration method is used to study harmonic excitation of smart structures. Numerical results are presented to induce harmonic vibration of structure with controlled magnitude via adjusting the damping and to verify the controlled resonant vibration formulation.
39
Liao, Ching-mao, e 廖景茂. "Tripod Type Piezoelectric Actuator". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/46494918518333994767.
Testo completoAbstract (sommario):
碩士正修科技大學
機電工程研究所
94
In this paper, a tripod type piezoelectric actuator with low rotational speed and high torque was discussed. The tripod type piezoelectric actuator consists of three piezoelectric legs and a base. Its dimensions and net weight was 82mm×73mm×57mm and 116 (gw). In addition,its maximum cw. rotational speed was 88.7 rpm under 100 Vp-p driving voltage, 49.4 kHz driving frequency and 140 (gw) loading. Its ccw. rotational speed was 59.8 rpm under 100Vp-p driving voltage, 49.78 kHz driving frequency and 140 (gw) loading. In addition, its maximum loading was 1390 (gw) under 100 Vp-p driving voltage, 49.4 kHz driving frequency and 34.4 rpm cw. rotational speed. And the maximum loading was 1340 (gw) under 100 Vp-p driving voltage, 49.78 kHz driving frequency and 25 rpm ccw. rotational speed.
40
Raghuvanshi, Digvijay Singh. "Novel actuation techniques for piezoelectric tube actuators". Thesis, 2018. http://hdl.handle.net/1959.13/1393703.
Testo completoAbstract (sommario):
Masters Research - Master of Philosophy (MPhil)Piezoelectric tube actuators are widely used in applications such as fibre optics alignment, endoscopy imaging and scanning probe microscopy. Piezoelectric tubes are thin-walled cylinders of radially poled piezoelectric ceramics. In almost all applications, the tube is fixed at one end and free at the other. A conventional tube in atomic force microscopy consists of quartered outer electrodes, which cover two-thirds of the length for lateral actuation. The remaining one-third of the length is covered by a circumferential electrode for vertical actuation. The inner surface is covered by a continuous electrode grounded at all times. For lateral actuation (bending) along the X or Y-direction, two outer quartered electrodes on opposite sides are driven by voltages of equal magnitude but opposite polarity. Voltage applied to the top circumferential electrode produces vertical actuation. The simplest way to increase the scan range of a piezoelectric tube actuator is to increase its length. However, this increases the physical size and reduces the resonance frequency. This thesis describes a new method for increasing the vertical scan range by driving the internal electrode rather than grounding it. This approach eliminates the need for a circumferential Z-electrode, which is typically one-third of the tube length, thereby allowing longer quadrant electrodes for larger lateral scan range. Since the proposed technique does not change the physical size of the tube, it is ideal for compact applications. Experimental results show a 62% increase in lateral scan range and an 86% increase in vertical scan range with negligible increase in cross-coupling. Analytical modelling shows that driving the internal electrode does not interfere with the lateral scan range. This thesis also proposes to implement similar technique for an eight-electrode tube actuator to compensate for angular (tilting) and vertical cross-coupling. The conventional quartered electrodes are split into two vertical segments of equal length to create a total of eight electrodes. The tilting and vertical cross-coupling due to the lower segments is compensated by the upper segments giving a sigmoid shape to the tube during lateral motion. Finite element simulations and experimental results confirm a 96% decrease in tilt angle and 43% reduction in vertical cross-coupling. However, the trade-off encountered with this method is a 44% decrease in lateral scan range.
41
Lin, Hung-Pin, e 林鴻賓. "Piezoelectric Actuator Modeling and Parameters Identification". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/87773726283844196058.
Testo completoAbstract (sommario):
碩士國立清華大學
動力機械工程學系
91
For the purpose of understanding the physical and chemical properties of the nano material as well as performing processing work on it, a manipulator with accuracy in the nano meter range is absolutely necessary. Typically, these nano-scale manipulators are driven piezoelectric actuators. Regardless of the advantages such as lightweight, fast response and high resolution, the piezoelectric actuator also exhibits hysteresis behavior which will seriously limit its performance. In order to achieve more precise control on the piezoelectric actuator, this research is devoted to identifying the hysteresis and developing an algorithm to eliminate the positioning error caused by such an effect. Particularly, we utilize the Maxwell model and Bond-Graph representation to model hysteresis and use the experimental data to estimate the parameters in the model. The model acquired is then used to design a feedforward control so that the piezoelectric actuator can have better positioning performance even when controlled in the open-loop manner.
42
Eddy, David. "Piezoelectric tool actuator for precision turning". Thesis, 1999. http://hdl.handle.net/2429/9290.
Testo completoAbstract (sommario):
High precision machining has the potential of increasing the efficiency of machining operations
and lowering costs in the manufacturing of many machined parts. This thesis investigates
the use of a piezoelectric tool/actuator designed for the precision turning of cylindrical shafts.
The piezo tool actuator has four fundamental components. The piezo stack element delivers a
dynamic displacement range of 40 μm when 0 to -1000V voltage is applied. The piezo element is
placed in a mechanical housing with leaf springs, which amplifies the displacement range to
62um. The piezo element is activated by an amplifier which delivers a maximum 150W and 0-
1000 V voltage. The digital control law runs on a PC/DSP which has 5KHz loop frequency. The
tool position is measured using a laser displacement sensor with 0.1 μm accuracy, and the workpiece
surface is monitored using another laser sensor which has 1 μm resolution. The piezo tool
actuator is mounted on a standard CNC turning center turret, and is intended to be used in precision
positioning of cutting tool within one micrometer during finish turning of shafts.
The mathematical model of each component in the dynamic system is identified. The piezoelectric
hysteresis is modeled using a time-delay model, and the actuator's transfer function is
identified experimentally by analytically indicating the source of dynamics. Several digital control
methodologies are developed for the actuator based upon the model generated. Pole placement,
zero phase error tracking, and state feedback control with a disturbance observation model
have been developed and cutting tests performed to evaluate their suitability for precision turning.
The mathematical model and experimental trials indicate that one to two micrometer displacement
can be best achieved using a feed-forward controller with state feedback disturbance
observer and rejection. The ability of the system in tracking highly dynamic position commands is
also demonstrated by turning elliptical shafts. The identified bandwidth of the actuator is found to
be about 500Hz, but the displacement ranged rapidly drops to ~12 μm at the peak frequency
Higher dynamic bandwidth and surface finish accuracy can be obtained if the mechanical
system is more rigidly designed, and the amplifier has more power to drive the piezoelectric element
at higher actuation frequencies.
43
Hou, Bing-Kuan, e 侯秉寬. "Power Driver Design for Piezoelectric Actuator". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/46762699790486168925.
Testo completoAbstract (sommario):
碩士中原大學
機械工程研究所
96
In this thesis, designing a power driver based on Class-D amplifier for piezoelectric actuator is the primary goal. Self oscillating PWM modulation is constructed with error amplifier, comparator, feedback controller, digital buffer, and level shifter. This modulation is able to convert analog signal to digital signal by switching signals in the feedback with no need of extra switching signals. Power amplifier modulation is composed of power drive and power amplifier, which makes use of switched-mode technique in order to gain higher power efficiency. Filter modulation is designed based upon the Butterworth filter associated with the characteristics of capacitive load of piezoelectric actuator. Such filter modulation can attenuate high-frequency synthesized signal so as to restore its original waveform efficiently. Finally, function test and performance evaluation is carried out in experiment.
44
YOUNG, SHIN WEN, e 楊實文. "Piezoelectric Inkjet Head- Design and Fabrication of Micro Array Piezoelectric Actuator". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/14146311682979223353.
Testo completoAbstract (sommario):
碩士大葉大學
機械工程學系碩士班
91
With the development of inkjet printing application technology, the inkjet print-head is not only occupying the traditional office printing market, but also making us to focus on it’s application, such as new organic/polymer lighting emitting display, optical communication devices, and MEMS devices, and engine technology etc. In many kinds of inkjet printing technology, the most favor type of inkjet printing technology is the piezoelectric driven printing technology. This study uses finite elements code, ANSYS, to analyze and design an actuator of a new type of shear mode piezoelectric ink jet head. Base on the actuated displacement and stoke volume change, the newly designed actuator model was optimized. The advantage of the model is use the most developed technology of making piezoelectric bulk. The piezoelectric actuator is poled by surface poling process, and owned different poling direction in the same piezoelectric material. Using electroplate process to fabricate a vibration membrane. Bonding both by epoxy and cutting the modulus by dicing saw. Measure the modulus properties such as displacement and compare with numerical simulation.
45
Hew, Kok-Foong, e 丘國鋒. "Analysis and Design of a Piezoelectric Actuator". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/70796863055314607043.
Testo completoAbstract (sommario):
碩士國立臺灣大學
工程科學及海洋工程學研究所
93
The primary aim of the research is to provide a comprehensive design process of the piezoelectric device. This simulation is based on Mason equivalent circuit model and transfer matrix method. Besides, the Smith chart, Return Loss and Transducer Loss have been carried out. The theory is applied to a piezoelectric device which excite 1.064μm acoustic wavelength to propagate in the substrate, three different materials of substrate have been chosen in the discussion. By using the Matlab simulation, several important factors including the influence of the bonding layer that affects the performance of piezoelectric transducers have been studied. Furthermore, the designs of matching network will be discussed. Finally, a piezoelectric device’s design procedure to offer a systematic way for the optimum designs of piezoelectric devices is presented.
46
Huang, Ji-Wei, e 黃紀威. "Fuzzy Control of a Piezoelectric Actuator System". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/97409940940113150343.
Testo completoAbstract (sommario):
碩士國立宜蘭大學
電機工程學系碩士班
96
The purpose of this thesis is to perform the nano-positioning control of a hysteresis system. First, the Bouc-Wen model describes the non-linear hysteresis curve of a piezoelectric actuator. Then, the Takagi-Sugeno (T-S) fuzzy model is applied to approximate the non-linear nano-positioning system. Last, the parallel distributed compensation is designed to control the piezoelectric actuator. Furthermore, the linear matrix inequality (LMI) approach is used to check the stability of fuzzy controller. The optimal parameters of the fuzzy control system are determined by the hybrid Taguchi method and particle swarm optimization.
47
顧孝鈞. "Fabrication and measurement of micro piezoelectric actuator". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/70671838155185053554.
Testo completoAbstract (sommario):
碩士大葉大學
機械工程研究所碩士班
92
The piezoelectric inkjet printhead play an important role in the developing industry of MEMS. The application of inkjet printing is very extensive in many fields. And, its key device, PZT actuator, attracts a lot of research attention and especially in MEMS field. But, up to now the actuating force of PZT actuator is difficult to measure in case of small size PZT in MEMS application. This study focuses on the improvement of piezoelectric characteristic for the actuating module of inkjet printhead. The actuating module consists of the PZT and the vibration plate. The PZT induce the deformation of diaphragm of vibration plate. The actuated out- of-plane displacement was measured by laser vibrometer (Polytec MSV300). And from the measured magnitude of the displacement the actuating force can be derived by numerical method and analytical formula.
48
Chan, Chin-Hsian, e 詹金祥. "Study of Double Disk Type Piezoelectric Actuator". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/01684869356137268956.
Testo completoAbstract (sommario):
碩士國立交通大學
工學院精密與自動化工程學程
100
This study proposes an innovative piezoelectric actuator. It has characteristics of large deformation and fast velocity. Under the inertial force and friction influence, the piezoelectric actuator can move rapidly. The piezoelectric actuator can reach 20mm displacement in this experiment. The experiments are carried out in two ways: one is drivien by same-direction voltage to piezoelectric element, which is called A-type. And another one driven by opposite-direction voltage, which is called B-type. The actuator experiments investigate the duty ratio and velocity effects, and the effects of the driving voltage on velocity and force. When the duty ratio is 40% or 60 %, the moving velocity of A-type is the fastest. According to experimental results concerning velocities and forces, A-type exhibits more deformation than B-type, so as to induce higher velocity and force. Therefore, A-type performs better than B-type.
49
Lai, Jun-An, e 賴俊安. "Two-Stage Driver Design for Piezoelectric Actuator". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/qmkd88.
Testo completoAbstract (sommario):
碩士中原大學
機械工程研究所
92
A driver for piezoelectric actuator for high and low range of frequency application is investigated. The first stage of the driver is boost DC converter associated with the full-bridge circuitry in the second stage. In low operating frequency, switching control with sinusoidal pulse width modulation (SPWM) is used in full-bridge circuitry, which converts the high voltage DC signal provided in the first stage into AC low frequency signal to drive the piezoelectric actuator. In high operating frequency, switching control with programmable pulse width modulation (PWM) is used in full-bridge circuitry in association with the high-voltage and high-frequency signal generated by the resonance circuitry. Single-chip microprocessor is used to design the programmable operating frequency with digital control method to accurately achieve the purpose.
50
Shiu, Shih-je, e 徐士哲. "Design of A Driver for Piezoelectric Actuator". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/06855730945517404806.
Testo completoAbstract (sommario):
碩士國立中正大學
機械工程所
98
In this thesis, we analyze the circuit of power amplifiers in the market, understand the working principle of the circuit, and use computer simulation to verify its correctness. Piezoelectric actuator driving circuit is divided into the power stage and the control stage. Part of the power stage is composed of half-bridge inverter and LC output filter. The Sigma-Delta Modulation is adopted to control the piezoelectric actuator.