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Mika, Bartosz. "Design and testing of piezoelectric sensors." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1565.
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Salehi-Khojin, Amin. "Vibration analysis of piezoelectric microcantilever sensors." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1211389804/.
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Lloyd, Carys Eleri. "The dynamic response of piezoelectric sensors." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612963.
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Barsky, Michael F. "Robot gripper control system using PVDF piezoelectric sensors." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/77897.
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A novel robot gripper control system is presented which uses PVDF piezoelectric sensors to actively damp exerted force. By using a low-input-resistance amplifier to sense the current developed by the PVDF sensor, an output proportional to the rate of change of the force exerted by the gripper is obtained. The signals from the PVDF sensor and a strain gauge force sensor are arranged in a proportional and derivative (PD) control system for the control of force. The control system was tested on an instrumented Rhino XR-1 manipulator hand. The capabilities of the control system are analyzed analytically, and verified experimentally. The results for this particular gripper indicate that as much as 900% improvement in force step response rise time, and 300% reduction in overshoot are possible by inclusion of the PVDF sensor.Master of Engineering
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Fu, Lei. "Application of Piezoelectric Sensors in Soil Property Determination." Case Western Reserve University School of Graduate Studies / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=case1089850793.
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LINDSEY, TIMOTHY J. "SELF-POWERED PIEZOELECTRIC SENSORS FOR VEHICLE HEALTH MONITORING." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085778333.
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Han, Yong 1969. "Detection of cracks in aircraft structures using piezoelectric sensors." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98964.
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Structural damage detection at the earliest possible stage is very important in the aerospace industry to prevent major failures. In this work, a potential cost-effective crack detection method using piezoelectric strips bonded on the structure was studied. A crack model was developed and validated. Static, modal and transient dynamic analysises are performed for the case of piezoelectric strips bonded to the structure by using a finite element method to explore the effectiveness of the crack detection method. Panel methods are used for steady flow problems of fixed wings in order to calculate the pressure distributions on the wing surface.A flat wing with a crack subjected to aerodynamic load was simulated to predict the presence of the crack. It is found that the voltage difference between the piezoelectric strips bonded at the same location (one on the upper side and the other on the lower side) can be used to predict the presence of the crack. For wing structure crack detection, the sensitivity is limited if the steady aerodynamic load is used as an excitation.
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Cotton, Darryl Paul James. "Thick-film piezoelectric slip sensors for a prosthetic hand." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444223.
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Boyd, Sharron. "An investigation into biological recognition coatings for piezoelectric sensors." Thesis, Glasgow Caledonian University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251229.
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Collins, Simon Andrew. "Sensors for structural control applications using piezoelectric polymer film." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/13613.
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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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Shen, Zuyan Shih Wan Y. Shih Wei-Heng. "Synthesis, fabrication, and characterization of self-exciting, self-sensing PZT/SiO2 piezoelectric micro-cantilever sensors /." Philadelphia, Pa. : Drexel University, 2006. http://hdl.handle.net/1860/1227.
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Newton, Cory Nelson. "Design and Frequency Characterization of Dual-Piezoresponsive Foam Sensors." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/9264.
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Multifunctional "self-sensing" materials at the frontiers of current research are generally designed to gather only a single type of information (such as quasi-static strain data). This project introduces a new sensor that is both multifunctional and dual-response, indicating its ability to not only perform in mechanical and sensing functions but also in its ability to sense multiple types of response. The proposed new class of sensing materials, comprised of nanocomposite polymer foams, exhibits measurable piezoresistive and quasi-piezoelectric phenomena in the form of change in resistance and voltage generation in response to deformation, respectively. An initial sampling of the envelope of dual-response nanocomposite foam sensors is mapped. The sensing materials can also be tailored to provide desired mechanical compliance and damping. Nanocomposite foam sensors decrease in resistance with increased strain in both static and cyclic compression environments. The quasi-piezoelectric voltage response of nanocomposite foam sensors increases linearly with compression frequency. A circuit and signal demodulation system was developed enabling simultaneous capture of a dual-response foam sensor's change in resistance and voltage generation. Measuring the two responses provides both long-term and immediate performance and health status of mechanical systems, enabling improved monitoring and decreased risk of failure.
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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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Frood, Andrew J. M. "Thick-film Piezoelectric resonant sensors : MEMS and High Temperature Solutions." Thesis, University of Southampton, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505870.
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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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Jackson, Cornelius Christiaan. "Tactile force-sensing for dynamic gripping using piezoelectric force- sensors." Thesis, Bloemfontein : Central University of Technology, Free State, 2009. http://hdl.handle.net/11462/34.
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Zhang, Chen. "Piezoelectric-Based Gas Sensors for Harsh Environment Gas Component Monitoring." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538769/.
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In this study, gas sensing systems that are based on piezoelectric smart material and structures are proposed, designed, developed, and tested, which are mainly aimed to address the temperature dependent CO2 gas sensing in a real environment. The state-of-the-art of gas sensing technologies are firstly reviewed and discussed for their pros and cons. The adsorption mechanisms including physisorption and chemisorption are subsequently investigated to characterize and provide solutions to various gas sensors. Particularly, a QCM based gas sensor and a C-axis inclined zigzag ZnO FBAR gas sensor are designed and analyzed for their performance on room temperature CO2 gas sensing, which fall into the scope of physisorption. In contrast, a Langasite (LGS) surface acoustic wave (SAW) based acetone vapor sensor is designed, developed, and tested, which is based on the chemisorption analysis of the LGS substrate. Moreover, solid state gas sensors are characterized and analyzed for chemisorption-based sensitive sensing thin film development, which can be further applied to piezoelectric-based gas sensors (i.e. Ca doped ZnO LGS SAW gas sensors) for performance enhanced CO2 gas sensing. Additionally, an innovative MEMS micro cantilever beam is proposed based on the LGS nanofabrication, which can be potentially applied for gas sensing, when combined with ZnO nanorods deposition. Principal component analysis (PCA) is employed for cross-sensitivity analysis, by which high temperature gas sensing in a real environment can be achieved. The proposed gas sensing systems are designated to work in a high temperature environment by taking advantage of the high temperature stability of the piezoelectric substrates.
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Papakostas, Thomas. "Polymer thick-film sensors and their integration with silicon : a route to hybrid microsystems." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342759.
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SARINK, NIEKE. "Characterization and Manufacturing of Textile Pressure Sensors based on Piezoelectric Fibres." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18054.
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The main purpose of this thesis was to investigate and characterize the use of piezoelectric yarn for use in textile (fingertip) pressure sensors in glove applications. Such applications could include healthcare, security and safety, game applications or intelligent control. Piezoelectric materials generate a voltage when pressed or squeezed. Poly(vinylidene fluoride) (PVDF) is a polymorphic material with piezoelectric properties. PVDF yarns were integrated into block sensors. These blocks consist of thermoplastic material glued to a knitted supporting fabric. The electrical signal given off by the PVDF yarn was measured with the help of an oscilloscope. The block sensor generated a distinguishable signal under a dynamic compression of 0.003 N, indicating that the structure is sensitive enough compared to the average male fingertip sensitivity threshold (0.0054N).Program: Master programme in Textile Engineering
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Gore, Kapil Suhling J. C. Jaeger Richard C. "Vibration analysis of test chips with integrated piezoresistive stress sensors." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/GORE_KAPIL_36.pdf.
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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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Zhang, Qiliang Lec Ryszard. "Characterization of the interfacial interactions between microparticles and surfaces using piezoelectric sensors /." Philadelphia, Pa. : Drexel University, 2006. http://hdl.handle.net/1860/1778.
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Medonza, Dharshan C. "AUTOMATIC DETECTION OF SLEEP AND WAKE STATES IN MICE USING PIEZOELECTRIC SENSORS." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/271.
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Currently technologies such as EEG, EMG and EOG recordings are the established methods used in the analysis of sleep. But if these methods are to be employed to study sleep in rodents, extensive surgery and recovery is involved which can be both time consuming and costly. This thesis presents and analyzes a cost effective, non-invasive, high throughput system for detecting the sleep and wake patterns in mice using a piezoelectric sensor. This sensor was placed at the bottom of the mice cages to monitor the movements of the mice. The thesis work included the development of the instrumentation and signal acquisition system for recording the signals critical to sleep and wake classification. Classification of the mouse sleep and wake states were studied for a linear classifier and a Neural Network classifier based on 23 features extracted from the Power Spectrum (PS), Generalized Spectrum (GS), and Autocorrelation (AC) functions of short data intervals. The testing of the classifiers was done on two data sets collected from two mice, with each data set having around 5 hours of data. A scoring of the sleep and wake states was also done via human observation to aid in the training of the classifiers. The performances of these two classifiers were analyzed by looking at the misclassification error of a set of test features when run through a classifier trained by a set of training features. The best performing features were selected by first testing each of the 23 features individually in a linear classifier and ranking them according to their misclassification rate. A test was then done on the 10 best individually performing features where they were grouped in all possible combinations of 5 features to determine the feature combinations leading to the lowest error rates in a multi feature classifier. From this test 5 features were eventually chosen to do the classification. It was found that the features related to the signal energy and the spectral peaks in the 3Hz range gave the lowest errors. Error rates as low as 4% and 9% were achieved from a 5-feature linear classifier for the two data sets. The error rates from a 5-feature Neural Network classifier were found to be 6% and 12% respectively for these two data sets.
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Wilson, Lester W. "Piezoelectric sensors incorporating electrostatic focusing and automated cleaning for personal aerosol monitoring." Thesis, Glasgow Caledonian University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308328.
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Wang, Xingjun. "Impact location in structures using elastic energy flow estimators with piezoelectric sensors." Lyon, INSA, 2009. http://theses.insa-lyon.fr/publication/2009ISAL0126/these.pdf.
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La détection et la quantification de chocs sur une structure mécanique reste une attente majeure dans de nombreuses thématiques, notamment celle du contrôle de santé structurel (Health monitoring). Les domaines les plus demandeurs sont sans nul doute l'aéronautique et l'aérospatiale où l'utilisation de plus en plus fréquente de structures composites rend leur suivi et leur contrôle de santé indispensables pour d'évidentes raisons de performances et de sécurités de fonctionnement. Savoir détecter et localiser des chocs, c'est avant tout savoir dresser un historique des impacts générés sur la structures et permettre ainsi de gérer au mieux le risque d'apparition d'endommagements structurels (casse, délaminage, déformation…). L'objectif central de ces travaux de thèse a porté sur la détection d'impact par l'estimation du flux d'énergie élastique induit (vecteur de Poynting) lors du choc. Ces estimateurs sont déduits des tensions électriques fournies par des éléments piézoélectriques collés sur la structure. Ces estimateurs sont déduits des tensions électriques fournies par des éléments piézoélectriques collés sur la structure. Il a ainsi été montré qu'il est envisageable de développer des estimateurs du flux d'énergie élastique induit par un choc sur une structure élastique et de pouvoir en tirer des informations concernant sa localisation ,voire son amplitude. L'approche théorique est complexe et nécessite une connaissance globale des divers couplages mis en jeu. Quoi qu'il en soit, ces techniques, de part leur simplicité de mise ne oeuvre et leur faible demande de moyens de calcul, constituent une proposition intéressante pour de futures techniques de détection d'impact passives ayant de plus la faculté d'être autoalimentables ; autrement dit, ayant la faculté de puiser directement dans les vibrations de la structure l'énergie suffisante pour assurer le calcul de l'estimateur et sa transmission par liaison sans filsDetection and quantification of impacts on elastic structure stays a major preoccupation in many fields, especially for Structural fields, especially for Structural HealthMonitoring (SHM). Aerospace and aeronautic are probably the more applicant industry sectors. Detecting impacts permits to prevent and supervise the risk of structural damage such as deformation, delamination, breakage… This work concerns with the impact detection based on induced elastic energy flow estimators. These quantities are here deduced from voltage of a piezoelements network embedded on the structure. The introduction is a state of the art in impact detection techniques. The pertinence of the present work is then justified by the need of a simplest approach using light mathematical estimators. In chapter 2, a new method is theoretically introduced and experimentally evaluate for a 1D structure (beam), exploiting electric response pf a piezoelectric sensors network. This simple technique,, easy to implement and totally passive. The 3rd chapter is devoted to the impulse response determination of an infinite plate in order to have the theoretical tools useful to estimate the impact force from the piezoelectric sensor voltage. The response from a particular impact is derived from the convolution of this impulse response by the representative impact force. In chapter 4, estimator of the Pounting vector direction is theoretically established from the voltage of piezoelectric elements for a 3D structure. In chapter 5, a new estimator of the Poynting vector is introduced. In addition of the energy flow direction, this estimator gives additional information on the energy flow amplitude in order to fully quantify the impact. In conclusion, these works show that these techniques are simples, easy to implement and do not have a high calculation capacity requirement. They are a new interesting offer for future passive impact detection techniques with moreover the capacity to be self-powered
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Zhu, Qing Shih Wei-Heng Shih Wan Y. "Characterization and application of piezoelectric microcantilever sensors fabricated from substrate-free PMN-PT layers /." Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2967.
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Grace, Jennifer L. "The utilization of piezoelectric materials and optical fiber sensors for electric field detection." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-05092009-040704/.
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Song, Li. "Application of electroless plating for fabrication of flexible and integrated piezoelectric ultrasonic sensors." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21961.
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Integrated (IUTs) and flexible ultrasonic transducers (FUTs) have been found to be of great interest for structural health monitoring (SHM) of graphite/epoxy (Gr/Ep) composite parts and structures. Because certain Gr/Ep composites do not have sufficient electrical conductivity, bottom electrodes are required for the IUT fabrication. Also FUTs using insulating polyimide (PI) membrane which offers high flexibility, bottom electrode is required as well. One main objective is to develop the electroless plating technique to deposit nickel (Ni) or silver (Ag) onto Gr/Ep composites and PI for IUT or FUT fabrication. The pre-treatments (cleaning, etching, sensibilization, activation and reduction) and reaction conditions (bath chemistry, temperature, time, agitation, etc.) have been investigated. Recipes of electroless nickel (EN) plating at room temperature (RT) and 90°C and RT electroless Ag plating have been developed. The interfacial adhesion of the Ni or Ag/substrate was also tested. The conductivity of the fabricated bottom electrodes was tested by ohmmeter. A 50~60µm piezoelectric film was fabricated by sol-gel spray technique. IUTs and FUTs consisting of these EN bottom electrodes, piezoelectric film and Ag paste top electrode perform well for SHM purposes.Les capteurs ultrasonores flexible (CUF) et intégré (CUI) sont très intéressants pour le suivi de la santé structurelle (SSS) des pièces de structures et de composites, composées à partir de carbone/époxyde (C/Ep). Parce que le C/Ep n'a pas suffisamment de conductivité électrique, une électrode de base est nécessaire pour la fabrication de CUIs. De plus, pour le CUF utilisant du polyimide (PI) comme membrane isolante nécessite aussi l'utilisation d'une électrode de base. Un des principaux objectifs de ce mémoire est de remédier à ce problème par le développement d'une technique de placage au tampon. Cette dernière déposera du nickel (Ni) ou de l'argent (Ag) sur le C/Ep et le PI pour obtenir des CUIs ou des CUFs. Les prétraitements (nettoyage, attaque chimique, sensibilisation, activation et réduction) et les conditions de réaction (bain chimique, température, temps, agitation, etc.) ont été étudiés. Les procédures pour le placage au tampon du nickel (PTN) à la température de la pièce (TP) et à 90C ainsi que pour l'Ag à TP furent développées. Les adhésions de surface du Ni ou de l'Ag avec le substrat furent testées. Les conductivités électriques des électrodes de base furent testées avec un ohmmètre. Un film piézo-électrique de 50~60 μm fut fabriqué par une technique sol-gel. Les CUI et CUF fabriqués avec l'électrode de base faite à partir du PTN, du film piézo-électrique et une pâte d'Ag comme électrode de surface, excelle bien pour les besoins en SSS.
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Contla, Pedro Jesus Acevedo. "On the nature of polymeric and ceramic sensors : (the modelling of piezoelectric transducers)." Thesis, Bangor University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305469.
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Newman, Scott M. "Active damping control of a flexible space structure using piezoelectric sensors and actuators." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23517.
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Approved for public release; distribution is unlimitedThis thesis details the experimental analysis of an active damping control technique applied to the Naval Postgraduate School's Flexible Spacecraft Simulator using piezoceramic sensors and actuators. The mass property of the flexible arm is varied to study the frequency effects on the Positive Position Feedback (PPF) algorithm. Multi-modal dynamics response is analytically studied using a finite-element model of a cantilevered beam while under the influence of three different control laws: a basic law derived rom the Lyapunov Stability Theorem, PPF and Strain Rate Feedback (SRF). The advantages and disadvantages of using PPF and SRF for active damping control are discussed.
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Parhad, Ashutosh. "Energy scavenging using piezoelectric sensors to power in pavement intelligent vehicle detection systems." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1603752.
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Intelligent transportation systems use in-pavement inductive loop sensors to collect real time traffic data. This method is very expensive in terms of installation and maintenance. Our research is focused on developing advanced algorithms capable of generating high amounts of energy that can charge a battery. This electromechanical energy conversion is an optimal way of energy scavenging that makes use of piezoelectric sensors. The power generated is sufficient to run the vehicle detection module that has several sensors embedded together. To achieve these goals, we have developed a simulation module using software’s like LabVIEW and Multisim. The simulation module recreates a practical scenario that takes into consideration vehicle weight, speed, wheel width and frequency of the traffic.
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Hinchet, Ronan. "Electromechanical study of semiconductor piezoelectric nanowires. Application to mechanical sensors and energy harvesters." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT013/document.
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Les systèmes intelligents sont le résultat combiné de différentes avancées en microélectronique et en particulier de l’augmentation des puissances de calcul, la diminution des consommations d’énergie, l'ajout de nouvelles fonctionnalités et de moyens de communication et en particulier à son intégration et application dans notre vie quotidienne. L'évolution du domaine des systèmes intelligents est prometteuse, et les attentes sont élevées dans de nombreux domaines : pour la surveillance dans l'industrie, les transports, les infrastructures et l'environnement, ainsi que dans le logement, l'électronique grand public et les services de soins de santé, mais aussi dans les applications pour la défense et l’aérospatial. Aujourd’hui, l'intégration de plus en plus de fonctions dans les systèmes intelligents les conduisent vers un problème énergétique où l'autonomie devient le principal problème. Par conséquent, il existe un besoin croissant en capteurs autonomes et sources d'alimentation. Le développement de dispositifs de récupération d’énergie et de capteurs autoalimentés est une façon de répondre à ce problème énergétique. Parmi les technologies étudiées, la piézoélectricité a l'avantage d'être compatible avec l'industrie des MEMS. De plus elle génère des tensions élevées et elle possède un fort couplage direct entre les physiques mécaniques et électriques. Parmi les matériaux piézoélectriques, les nanofils (NFs) semi-conducteurs piézoélectriques pourraient être une option prometteuse car ils présentent des propriétés piézoélectriques plus importantes et une plus grande gamme de flexion.Parmi les différents NFs piézoélectriques, les NFs de ZnO et de GaN sont les plus étudiés. A l'échelle nanométrique leurs propriétés piézoélectriques sont plus que doublées. Ils ont l'avantage d'être compatible avec l’industrie microélectronique et raisonnablement synthétisable par des approches top-down et bottom-up. En particulier, nous avons étudié la croissance par voie chimique de NFs de ZnO. Pour les utiliser correctement, nous avons étudié le comportement des NFs de ZnO. Nous avons effectué une étude analytique et des simulations par éléments finis (FEM) d'un NF de ZnO en flexion. Ces études décrivent la distribution du potentiel piézoélectrique en fonction de la force et permettent d’établir les règles d'échelle et de dimensionnement. Ensuite, nous avons développé la caractérisation mécanique par AFM du module de Young de NFs de ZnO et de GaN, puis nous avons effectué des caractérisations piézoélectriques par AFM de ces NFs pour vérifier leur comportement sous des contraintes mécaniques de type flexion. Une fois leur comportement physique compris, nous discutons des limites de notre modèle de NFs piézoélectriques en flexion et nous développons un modèle plus réaliste et plus proche des configurations expérimentales. En utilisant ce nouveau modèle, nous avons évalué le potentiel des NFs de ZnO pour les capteurs de force et de déplacement en mesurant le potentiel généré sous une contrainte, puis, sur la base d’expériences, nous avons évalué l'utilisation de NFs de GaN pour les capteurs de force en mesurant le courant au travers des NFs contraints. De même, nous avons évalué le potentiel de ces NFs pour les applications de récupération d'énergie liées aux capteurs autonomes. Pour bien comprendre la problématique, nous avons étudié l’état de l’art des nano générateurs (NG) et leurs architectures potentielles. Nous analysons leurs avantages et inconvénients, afin de définir une structure de NG de référence. Après une brève étude analytique de cette structure pour comprendre son fonctionnement et les défis, nous avons effectué plusieurs simulations FEM pour définir des voies d'optimisation pour les NG utilisé en mode de compression ou de flexion. Enfin la fabrication de prototypes et leurs caractérisations préliminaires sont présentéesSmart systems are the combined result of different advances in microelectronics leading to an increase in computing power, lower energy consumption, the addition of new features, means of communication and especially its integration and application into our daily lives. The evolution of the field of smart systems is promising, and the expectations are high in many fields: Industry, transport, infrastructure and environment monitoring as well as housing, consumer electronics, health care services but also defense and space applications. Nowadays, the integration of more and more functions in smart systems is leading to a looming energy issue where the autonomy of such smart systems is beginning to be the main issue. Therefore there is a growing need for autonomous sensors and power sources. Developing energy harvesters and self-powered sensors is one way to address this energy issue. Among the technologies studied, piezoelectricity has the advantage to be compatible with the MEMS industry, it generates high voltages and it has a high direct coupling between the mechanic and electric physics. Among the piezoelectric materials, semiconductor piezoelectric nanowires (NWs) could be a promising option as they exhibit improved piezoelectric properties and higher maximum flexion.Among the different piezoelectric NWs, ZnO and GaN NWs are the most studied, their piezoelectric properties are more than doubled at the nanoscale. They have the advantage of being IC compatible and reasonably synthesizable by top-down and bottom-up approaches. Especially we studied the hydrothermal growth of ZnO NWs. In order to use them we studied the behavior of ZnO NWs. We performed analytical study and FEM simulations of a ZnO NW under bending. This study explains the piezoelectric potential distribution as a function of the force and is used to extract the scaling rules. We have also developed mechanical AFM characterization of the young modulus of ZnO and GaN NWs. Following we perform piezoelectric AFM characterization of these NWs, verifying the behavior under bending stresses. Once physics understood, we discuss limitation of our piezoelectric NWs models and a more realistic model is developed, closer to the experimental configurations. Using this model we evaluated the use of ZnO NW for force and displacement sensors by measuring the potential generated, and from experiments, the use of GaN NW for force sensor by measuring the current through the NW. But energy harvesting is also necessary to address the energy issue and we deeper investigate this solution. To fully understand the problematic we study the state of the art of nanogenerator (NG) and their potential architectures. We analyze their advantages and disadvantages in order to define a reference NG structure. After analytical study of this structure giving the basis for a deeper understanding of its operation and challenges, FEM simulations are used to define optimization routes for a NG working in compression or in bending. The fabrication of prototypes and theirs preliminary characterization is finally presented
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Hoffmann, Sandra. "A parametric level set method for the design of distributed piezoelectric modal sensors." Doctoral thesis, Universite Libre de Bruxelles, 2016. https://dipot.ulb.ac.be/dspace/bitstream/2013/229594/5/ContratSH.pdf.
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Distributed modal filters based on piezoelectric polymer have especially become popular in the field of active vibration control to reduce the problem of spillover. While distributed modal filters for one-dimensional structures can be found analytically based on the orthogonality between the mode shapes, the design for two-dimensional structures is not straightforward. It requires a continuous gain variation in two dimensions, which is not realizable from the current manufacturing point of view. In this thesis, a structural optimization problem is considered to approximate distributed modal sensors for two-dimensional plate structures, where the thickness is constant but the polarization can switch between positive and negative. The problem is solved through an explicit parametric level set method. In this framework, the boundary of a domain is represented implicitly by the zero isoline of a level set function. This allows simultaneous shape and topology changes. The level set function is approximated by a linear combination of Gaussian radial basis functions. As a result, the structural optimization problem can be directly posed in terms of the parameters of the approximation. This allows to apply standard optimization methods and bypasses the numerical drawbacks, such as reinitialization, velocity extension and regularization, which are associated with the numerical solution of the Hamilton-Jacobi equation in conventional methods.Since the level set method based on the shape derivative formally only allows shape but not topology transformation, the optimization problem is firstly tackled with a derivative-free optimization algorithm. It is shown that the approach is able to find approximate modal sensor designs with only few design variables. However, this approach becomes unsuitable as soon as the number of optimization variables is growing. Therefore, a sensitivity-based optimization approach is being applied, based on the parametric shape derivative which is with respect to the parameters of the radial basis functions. Although the shape derivatives does not exist at points where the topology changes, it is demonstrated that an optimization routine based on a SQP solver is able to perform topological changes during the optimization and finds optimal designs even from poor initial designs. In order to include the sensors' distribution as design variable, the parametric level set approach is extended to multiple level sets. It turns out that, despite the increased design space, optimal solutions always converge to full-material polarization designs. Numerical examples are provided for a simply supported as well as a cantilever square plate.Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
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Mommaerts, Joseph. "A feasibility study of PVDF piezoelectric sensors to detect damage in adhesive joints." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41993.
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Cortes, Correales Daniel H. "Elastic guided wave dispersion in layered piezoelectric plates application to ultrasound transducers and acoustic sensors /." Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10206.
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Thesis (Ph. D.)--West Virginia University, 2009.Title from document title page. Document formatted into pages; contains vi, 84 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 79-84).
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Hixenbaugh, Franklin D. "A study on piezoelectric actuators and sensors for vibration control of flexible space structures." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA274925.
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Thesis (M.S. in Systems Technology (Space Systems Operations)) Naval Postgraduate School, September 1993.Thesis advisor(s): Brij N. Agrawal. "September 1993." Includes bibliographical references. Also available online.
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Gooch, Steven R. "A METHOD FOR NON-INVASIVE, AUTOMATED BEHAVIOR CLASSIFICATION IN MICE, USING PIEZOELECTRIC PRESSURE SENSORS." UKnowledge, 2014. http://uknowledge.uky.edu/ece_etds/56.
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While all mammals sleep, the functions and implications of sleep are not well understood, and are a strong area of investigation in the research community. Mice are utilized in many sleep studies, with electroencephalography (EEG) signals widely used for data acquisition and analysis. However, since EEG electrodes must be surgically implanted in the mice, the method is high cost and time intensive. This work presents an extension of a previously researched high throughput, low cost, non-invasive method for mouse behavior detection and classification. A novel hierarchical classifier is presented that classifies behavior states including NREM and REM sleep, as well as active behavior states, using data acquired from a Signal Solutions (Lexington, KY) piezoelectric cage floor system. The NREM/REM classification system presented an 81% agreement with human EEG scorers, indicating a useful, high throughput alternative to the widely used EEG acquisition method.
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Bao, Yuanye. "Development and Test of High-Temperature Piezoelectric Wafer Active Sensors for Structural Health Monitoring." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc799504/.
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High-temperature piezoelectric wafer active sensors (HT-PWAS) have been developed for structure health monitoring at hazard environments for decades. Different candidates have previously been tested under 270 °C and a new piezoelectric material langasite (LGS) was chosen here for a pilot study up to 700 °C. A preliminary study was performed to develop a high temperature sensor that utilizes langasite material. The Electromechanical impedance (E/M) method was chosen to detect the piezoelectric property. Experiments that verify the basic piezoelectric property of LGS at high temperature environments were carried out. Further validations were conducted by testing structures with attached LGS sensors at elevated temperature. Additionally, a detection system simulating the working process of LGS monitoring system was developed with PZT material at room temperature. This thesis, for the first time, (to the best of author’s knowledge) presents that langasite is ideal for making piezoelectric wafer active sensors for high temperature structure health monitoring applications.
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Armstrong, Elizabeth Gene. "Investigation Into Use of Piezoelectric Sensors in a Wheeled Robot Tire For Surface Characterization." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/51146.
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A differential steered, 13.6 kg robot was developed as an intelligent tire testing system and was used to investigate the potential of using piezoelectric film sensors in small tube-type pneumatic tires to characterize tire-ground interaction.One focus of recent research in the tire industry has been on instrumenting tires with sensors to monitor the tire, vehicle, or external environment. On small robots, tire sensors that measure the forces and deflections in the contact patch could be used to improve energy efficiency and/or mobility during a mission.
The robot was assembled from a SuperDroid Robots kit and instrumented with low-cost piezoelectric film sensors from Measurement Specialties between the inner tube and the tire. An unlaminated and a laminated sensor were placed circumferentially along the tread and an unlaminated sensor was placed along the sidewall. A slip ring transferred the signals from the tire to the robot. There, the signal conditioning circuit extended the time constant of the sensors and filtered electromagnetic interference. The robot was tested with a controlled power sequence carried out on polished cement, ice, and sand at three power levels, two payload levels, and with two tire sizes.
The results suggest that the sensors were capable of detecting normal pressure, deflection, and/or longitudinal strain. Added payload increased the amplitude of the signals for all sensors. On the smaller tires, sensors generally recorded a smaller, wider signal on sand compared to cement, indicating the potential to detect contact patch pressure and length. The signals recorded by the unlaminated sensor along the tread of the smaller tire were lower on ice compared to cement, indicating possible sensitivity to tractive force. Results were less consistent for the larger tires, possibly due to the large tread pattern.
Master of Science
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Campbell, Gossett A. Mutharasan Rajakannu. "Detection and quantification of pathogens, proteins, and molecules using piezoelectric-excited millimeter-sized cantilever (PEMC) sensors /." Philadelphia, Pa. : Drexel University, 2006. http://dspace.library.drexel.edu/handle/1860/737.
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Tinoco, Navarro Hector Andrés. "Análise numérica e experimental dos efeitos da descolagem na resposta elétrica de sensores piezelétricos." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264938.
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Orientador: Alberto Luiz SerpaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-18T13:10:19Z (GMT). No. of bitstreams: 1 TinocoNavarro_HectorAndres_M.pdf: 12075431 bytes, checksum: cab5c2f419dac7a4f94391f21804ed8d (MD5) Previous issue date: 2011
Resumo: Neste trabalho foi desenvolvido um estudo numérico e experimental com o objetivo de compreender os efeitos da descolagem nos sinais elétricos obtidos por meio de sensores piezelétricos. Na análise numérica, os deslocamentos do sistema acoplado estrutura-adesivosensor foram representados em equações diferenciais para os casos estático e dinâmico. Os sinais elétricos emitidos pelos sensores foram determinados pelos deslocamentos para diferentes parâmetros geométricos da interface adesiva. Os resultados numéricos mostram que as propriedades geométricas da interface adesiva modificam as condições de deformação entre o sensor e a estrutura. Também, foi proposto um sensor com três eletrodos com o qual foram estabelecidas relações de força. As relações de força mostraram que as propriedades do adesivo podem diminuir as forças nos extremos do sensor e assim evitar descolagem. As simulações de descolagem do sensor foram realizadas com o aplicativo computacional COMSOL. As soluções numéricas dinâmicas indicaram que um sensor descolado gera menor potência elétrica que um sensor completamente colado. Isto foi comprovado experimentalmente em três casos e os resultados experimentais concordaram com os resultados teóricos. Este estudo demonstrou que a descolagem parcial não pode ser considerada uma falha de adesão, já que o sensor pode emitir sinais elétricos quando o sensor está descolado. Também foi demonstrado que a descolagem afeta o rendimento elétrico dos sensores
Abstract: In this investigation it was developed a numerical and experimental study with the aim to understand the debonding effects on electrical signatures obtained by means of piezoelectric sensors. In the numerical analysis, the displacements of the coupled system structure-adhesivesensor were represented by differential equations for static and dynamic cases. Electrical signatures emitted by sensors were determined through the displacements for different geometric parameters of the adhesive interface. Numerical results show that geometric properties of the adhesive interface modify the deformation conditions between the sensor and the structure. Also, a sensor was proposed with three electrodes in which were established force relations between each electrode. Force relations shown that the properties of adhesive can diminish the forces in the end of the sensor avoiding debonding. Simulations of debonding of the sensor were carried out with COMSOL software. Dynamic numerical solutions indicate that debonded sensor generates electric power lower than a sensor completely bonded. This was proved experimentaly in three cases and the experimental results presented good agreement. This study demonstrated that the partial debonding cannot be considered as a fail by adhesion, since the sensor can emit electrical signatures when it is partially debonded. Also it was demonstrated that the debonding of the sensor affects electric performance
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
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Edwards, Michael. "Modelling, fabrication and development of GaN-based sensors and substrates for high strain environments." Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669016.
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GaN is a monocrystalline material that can be grown using metallo-organic chemical vapour deposition (MOCVD), and has desirable mechanical and semiconducting properties for operating as a sensor. It has a Young’s modulus of 250 to 350 GPa, which shows little decrease with respect to temperature beyond 400°C. GaN also exhibits piezoelectric and piezoresistive effects, meaning that it will generate a charge and its electrical resistance will change when the material is strained respectively. In this PhD, GaN has been used as the base material for pressure sensors that potentially can be used in excess of 400°C and at a pressure in excess of 50 bar (5 MPa), with potential applications in aerospace and oil exploration. The pressure sensor is a circular diaphragm created from a GaN/sapphire wafer, and was designed and tested in order to determine if GaN can act as a sensing material in these environments. In addition to the diaphragm sensor, GaN templates that can potentially be used for sensors were grown using an epitaxial layer overgrowth (ELOG) method. These sensors are potentially more mechanically robust than similar templates etched out of GaN/sapphire wafers because they will have less inbuilt strain due to lower dislocation densities. It was possible to release beams and cantilevers from GaN ELOG templates. Mechanical probe tests were undertaken on these devices to see if they were fully released and robust. GaN single crystal growth requires a substrate material, such as (111) silicon or (0001) sapphire, meaning that the thermal properties of the substrate are important for a device operating in excess of 400°C. GaN high electron mobility transistors are heat sensitive, experiencing a decrease in current between the drain and source terminals as the temperature increases. Therefore a GaN-based sensor needs a substrate with the highest possible thermal conductivity to act as a heat sink, which means removing as much heat as possible from the GaN sensor. Diamond has superior thermal conductivity to both sapphire and silicon, so a novel silicon/polycrystalline diamond composite substrate has been developed as a potential GaN substrate. Polycrystalline diamond (PD) can be grown on 4 inch diameter wafers using hot filament chemical vapour deposition (CVD), on (111) silicon (Si) from which single crystal GaN epitaxy can also be grown. In order for the (111) Si/PD composite substrates to be useful heat sinks, the Si layer needs to be less than 2 m. PD was initially grown on 525 to 625 m thick Si wafers that required thinning to 2 m. Achieving this Si layer thickness is difficult due to the presence of tensile stress in the Si caused by a mismatch in the coefficients of thermal expansion (CTEs) between Si and PD. This stress causes the wafer to bow significantly and has been modelled using ANSYS FE software. The models show that the bow of the wafer increases when it is thinned, which will eventually cause the Si layer to delaminate at the Si/PD interface due to poor adhesion and a build up for shear stress. When the Si layer is mechanically thinned, the Si layer can crack due to clamping. The experimental wafer bow and micro-Raman measurements validate the model for when the silicon layer is thicker than 100 m and these results show that an alternative processing route is required.
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FAN, HUI. "A BOUNDARY ELEMENT METHOD FOR THE ANALYSIS OF THIN PIEZOELECTRIC SOLIDS." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin988811258.
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SHINDE, VISHAL. "DEVELOPMENT OF A DATA ACQUISITION SYSTEM AND PIEZOELECTRIC SENSORS FOR AN EXPERIMENTAL STRUCTURAL NEURAL SYSTEM." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1143842747.
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Anderson, Gregory Lee. "The development of poly(vinylidene fluoride) piezoelectric sensors for measuring peel stresses in adhesive joints." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/39881.
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Although bond-normal stresses have been shown to be responsible for the failure of most laboratory adhesive joint geometries, the measurement of these stresses has been accomplished only through the use of very sophisticated optical techniques. In order to develop a more versatile measurement technique, poly(vinylidene fluoride) film was used to develop piezoelectric stress sensors. The sensitivities of the film to normal stresses in the three principal material directions of the orthotropic film were accurately measured using a charge amplifier and a storage oscilloscope. These measured sensitivities comprised the calibration constants of the film.
In order to reduce the detrimental effect on bond strength caused by embedding the low surface energy film into adhesive bondlines, surface treatment methods were investigated using contact angle studies, XPS analysis and 1800 peel and tapered double cantilever beam adhesion specimens. An acid etch using a mixture of acetic, phosphoric and nitric acids was found to greatly improve the bond strengths to an epoxy adhesive without reducing the piezoelectric activity of the film.
The bond-normal stresses in both the elastomeric butt joint and the single lap shear joint were measured using the developed stress sensors. Comparison of the measured stresses with calculated values obtained from closed-form analytical solutions and finite element analysis for the stresses was excellent.
The piezoelectric sensors do have several important limitations. The piezoelectric activity of the film is lost at temperatures above 100°C (210°F). Also, the sensors are only sensitive to dynamic loads. Nonetheless, the sensors provide an accurate means of measuring peel stresses in many adhesive joints of practical interest.Ph. D.
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Jha, Akhilesh K. "Vibration Analysis and Control of an Inflatable Toroidal Satellite Component Using Piezoelectric Actuators and Sensors." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/28243.
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Inflatable structures have been a subject of renewed interest in recent years for space applications such as communication antennas, solar thermal propulsion, and entry/landing systems. This is because inflatable structures are very lightweight and on-orbit deployable. In addition, they have high strength-to-mass ratio and require minimal stowage volume, which makes them especially suitable for cost-effective large space structures. An inflated toroidal structure (torus) is often used there in order to provide structural support. For these structures to be effective, their vibration must be controlled while keeping the weight low. Piezoelectric materials have become strong candidates for actuator and sensor applications in the active vibration control of such structures due to their lightweight, conformability to the host structure, and distributed nature. In this study, our main focus is to understand the dynamic characteristics of an inflatable torus and to control its vibration using piezoelectric actuators and sensors.
The first part of this study is concerned with theoretical formulations. We use Sanders' shell theory to derive the governing equations of motion for a shell subjected to pressure. To take into account the prestress effects of internal pressure, we use geometric nonlinearity, and to model the follower action of pressure force, we consider the work done by internal pressure during the vibration of the shell. These equations are then specialized to obtain approximate equations presented by previous researchers. We extend this analytical formulation to derive the equivalent forces due to piezoelectric actuators in unimorph and bimorph configurations and include their mass and stiffness effects in the governing equations. A sensor equation is also developed for the shell. The actuator and sensor equations are then written in terms of modal displacements and velocities so as to evaluate their interactions with different vibratory modes.
In the second part, we focus on numerical studies related to an inflated torus. At first, we perform a free vibration analysis of the inflated torus using Galerkin's method. We study how different parameters (aspect ratio, internal pressure, and wall-thickness) of the inflated torus affect the natural frequencies and mode shapes of the inflated torus. We compare the results obtained from the theory used in this research with the results from different approximate theories and commercial finite element codes. The results suggest that the use of an accurate shell theory and pressure effect is very important for the vibration analysis of an inflated torus. Next, the modal behaviors of piezoelectric actuator and sensor are analyzed. A detailed study is done in order to understand how the size and location of actuator and sensor affect the modal forces, the modal sensing constants, and the overall performance for all the considered modes. In order to determine the optimal locations and sizes of actuators and sensors, we use a genetic algorithm. Natural frequencies and mode shapes are calculated considering the passive effects of actuators and sensors. Finally, we attempt the vibration control of the inflated torus using the optimally designed actuators and sensors and sliding mode controller/observer. The numerical simulations show that piezoelectric actuators and sensors can be used in the vibration control of an inflatable torus. The robustness properties of the controller and observer against the parameter uncertainty and disturbances are verified.Ph. D.
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Dunbabin, Matthew D. "The influence of temperature on PZT sensors & actuators for active vibration control of flexible structures." Thesis, Queensland University of Technology, 2002. https://eprints.qut.edu.au/36162/7/36162_Digitised%20Thesis-4_Redacted.pdf.
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In real operating environments, flexible structures exhibiting dynamic oscillations such as aircraft and spacecraft can experience large changes in temperature during their normal operating cycle, typically in the range -70 to 80 degrees Celsius. The use of piezoelectric actuators and sensors to control these dynamic oscillations have been widely explored at constant temperature, although only limited studies have been conducted on the effect that varying temperature has on the active control of flexible structures.
The objective of this research is to study the influence of PZT sensors and actuators for vibration control of flexible structures where nonlinearities in piezoelectric and structural material properties change as the system temperatures vary significantly with time. This involved the development of a set of data based parameters that enabled the accurate modelling of a nonlinear flexible system in which its dynamics are actively controlled via the use of piezoelectric sensors and actuators. These parameters determined the design of a control scheme to actively control the system over a large range of operating temperatures, and give an optimised control performance throughout its operating regime.
The work reported in this thesis describes selected methods for rapidly examining a number of the more common nonlinear properties of PZT associated with vibration control. An extensive numerical and experimental investigation is performed which shows that when used in active vibration control applications, the variations in PZT properties with temperature can ultimately affect the ability of the piezoelectric actuator and sensors to suppress vibration in flexible structures.
Accurate simulation models of the lightweight piezo-actuated cantilevered structures were developed to evaluate the performance of a number of common vibration control schemes subject to significant temperature variations. This research was then extended to an innovative scaled wing-type structure subjected to temperature variations. A suitable adaptive self-tuning control scheme was developed and investigated numerically and experimentally, illustrating the benefit of adaptive control in this instance. The adaptive control technique was shown numerically and experimentally to provide improved settling times and damping ratios over equivalent fixed gain controllers for the class of structures investigated where limited control authority exists.
The experimental investigation of PZT sensors and actuators has provided further understanding of the nonlinear behaviour of various light, flexible structures where temperature effects on the system dynamics and control are significant. This research has unveiled previously unreported nonlinearities and has expanded on traditional nonlinearities. These results can assist with the detailed design of applications involving PZT sensors and actuators in for example the aerospace and automotive industries.
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Chung, Yao-kuang, and 鍾曜光. "Miniature Piezoelectric Ultrasonic Detection Sensors." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/17447016201784778880.
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碩士國立臺灣大學
機械工程學研究所
89
An ultrasonic detection sensor employed in a DC brushless motor driver can be realized by the commercially available ultrasonic emitter. The motion sensor includes only one ultrasonic emitter. By detecting reflection of an emitted ultrasonic wave, the rotating position of the motor can be distinguished and the magnetization direction of the motor coil can be determined. Since the rotation speed of the DC brushless motor can be theoretically controlled to 10,000 rpm The application of the sensor is expected to be appropriate due to its excellence properties to work in a high electromagenic interference environment and to resist high temperature that is lower than PZT Curie temperature. The work also tries to develop a miniature ultrasonic emitter for the motion detection. The circuit design and simulation is analyzed by software PSpice. As well as the circuit simulation, the relation between the dimension of the piezoelectric membrane and its resonance frequency is simulated and analyzed by a FEM software, namely ABAQUS. Therefore, the dimension of the ultrasonic sensor can be estimated. Furthermore, the fabrication of the miniature detection sensor by micro-electric-mechanical system (MEMS) technology is also presented. A PZT layer is formed by using both the metal-organic decomposition (MOD) method and the sputtering method in this work. A piezoelectric thin film with thickness of 0.5mm is made by MOD process and for the thickness with 1mm is made by sputtering process. As a result, important fabrication conditions and recipes have been obtained and established in this work for future applications in related field.
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Wu, Jenny-Feng, and 吳建鋒. "Analysis fot Piezoelectric Sensors and Actuators." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/44493871682904783339.
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碩士逢甲大學
機械工程學系
88
Although many methods are known for the analysis of piezoelectric materials and their applications, not much analytical work has been done in the field of one-dimensional piezoelectric sensors and actuators. It is the purpose of this thesis to present a general and simple approach for examining the electromechanical responses of piezoelectric materials. In this thesis, piezoelectric sensors/actuators are initially modeled as an engineering beam in which stresses and electric fields are taken as independent variables in the piezoelectric constitutive equations. In case of the beam excited by electromechanical and/or electric input, the general solutions for electromechanical responses of piezoelectric sensors/actuators are acquired in closed forms. In terms of analyzing PZT-4 and PIC-151 materials, numerical results of the proposed formulation are compared with those of ANSYS and ESPI experimental data. It is shown that numerical results of the proposed formulation correlate well with ANSYS as well as experimental results regarding frequencies. Finally, the proposed formulation is successfully extended to investigate piezoelectric laminated plates composite laminates.