Academic literature on the topic 'Electromechanical harvesting'
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Journal articles on the topic "Electromechanical harvesting"
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Guo, Chuan, and Albert C. J. Luo. "Nonlinear piezoelectric energy harvesting induced through the Duffing oscillator." Chaos: An Interdisciplinary Journal of Nonlinear Science 32, no. 12 (December 2022): 123145. http://dx.doi.org/10.1063/5.0123609.
Full textAbstract:
In this paper, nonlinear piezoelectric energy harvesting induced by a Duffing oscillator is studied, and the bifurcation trees of period-1 motions to chaos for such a piezoelectric energy-harvesting system are obtained analytically. Distributed-parameter electromechanical modeling of a piezoelectric energy harvester is presented first, and the electromechanically coupled circuit equation excited by infinitely many vibration modes is developed. The governing electromechanical equations are reduced to ordinary differential equations in modal coordinates, and eventually an infinite set of algebraic equations is obtained for the complex modal vibration responses and the complex voltage responses of the energy harvester beam. One single mode case is considered in this paper, and periodic motions with bifurcation trees are obtained through an implicit discrete mapping method. The frequency–amplitude characteristics of periodic motions are obtained for the nonlinear piezoelectric energy-harvesting systems, which provide a better understanding of where and how to achieve the best energy harvesting. This study describes about how the nonlinear oscillator induces piezoelectric energy harvesting through a beam system. The nonlinear piezoelectric energy harvesting is presented through a nonlinear oscillator. Due to the nonlinear oscillator, chaotic piezoelectric energy-harvesting states can get more energy compared to the linear piezoelectric energy-harvesting system.
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Thakur, Garima, and V. Velmurugan. "Electromechanical Piezoelectric Based Energy Harvesting System." Advanced Science Letters 24, no. 8 (August 1, 2018): 6030–33. http://dx.doi.org/10.1166/asl.2018.12241.
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Energy harvesting is a very attractive method in all the applications where battery replacement or recharging is difficult. We can harvest energy using environmental vibrations caused because of frequencies that are present naturally in our environment. Vibration energy can scavenge energy from mechanical vibrations to energies low power electronic devices. Low frequencies energy harvesting system can begin to replace batteries in certain wearable devices. As piezoelectric vibration based energy harvester and do not require external voltage and also they are not expensive making them feasible alternative to implement energy harvesting. In this paper we are investigating a bimorph piezoelectric cantilever geometry by using COMSOL Multiphysics 5.2. Material used is Lead Zirconate Titanate (PZT 5A), and stainless steel.
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Proksch, Roger, and Sergei Kalinin. "Piezoresponse Force Microscopy." Microscopy Today 17, no. 6 (November 2009): 10–15. http://dx.doi.org/10.1017/s1551929509990988.
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Coupling between electrical and mechanical phenomena is an important feature of functional inorganic materials and biological systems alike. The applications of electromechanically active materials include sonar, ultrasonic and medical imaging, sensors, actuators, and energy-harvesting technologies, as well as non-volatile computer memories. Electromechanical coupling in electromotor proteins and cellular membranes is the universal basis for biological functionalities from hearing to cardiac activity. The future will undoubtedly see the emergence of broad arrays of piezoelectric, biological, and molecular-based electromechanical systems to allow mankind the capability not only to “think” but also “act” on the nanoscale. The need for probing electromechanical functionalities has led to the development of Piezoresponse Force Microscopy (PFM) as a tool for local nanoscale imaging (Figures 1 and 2), spectroscopy, and manipulation of piezoelectric and ferroelectric materials.
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Yamamoto, Brennan E., and A. Zachary Trimble. "An experimentally validated analytical model for the coupled electromechanical dynamics of linear vibration energy harvesting systems." Journal of Intelligent Material Systems and Structures 28, no. 1 (July 28, 2016): 3–22. http://dx.doi.org/10.1177/1045389x16642304.
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Recent technological advancements in the efficiency of microprocessors, sensors, and other digital logic systems have increased research effort in vibration energy harvesting, where trace amounts of energy are scavenged from the ambient environment to provide power. Due to the complexity and nonlinearity of most vibration energy harvesting systems, existing research has relied primarily on numerical and finite element methods for harvester design and validation. Although these methods are useful, a vetted analytical model provides intuitive understanding of the governing dynamics and is useful for obtaining rough calculations when designing vibration energy harvesting systems. In this article, an analytical framework for linear electromechanical transducer modeling is developed into the coupled electromechanical model; a transfer function characterizing the dynamics of second-order VEH systems, which includes inputs for mechanical and electrical domain lumped parameters as complex impedances. The coupled electromechanical model transfer function is validated against frequency sweep data from a linear vibration energy harvesting experimental setup. The experimental setup demonstrated good correlation with the coupled electromechanical model, with not more than 0.9% error in natural frequency overall, 6% error in damping ratio for purely resistive loads, and 11% for reactive loads.
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LeGrande, Joshua, Mohammad Bukhari, and Oumar Barry. "Effect of electromechanical coupling on locally resonant quasiperiodic metamaterials." AIP Advances 13, no. 1 (January 1, 2023): 015112. http://dx.doi.org/10.1063/5.0119914.
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Electromechanical metamaterials have been the focus of many recent studies for use in simultaneous energy harvesting and vibration control. Metamaterials with quasiperiodic patterns possess many useful topological properties that make them a good candidate for study. However, it is currently unknown what effect electromechanical coupling may have on the topological bandgaps and localized edge modes of a quasiperiodic metamaterial. In this paper, we study a quasiperiodic metamaterial with electromechanical resonators to investigate the effect on its bandgaps and localized vibration modes. We derive here the analytical dispersion surfaces of the proposed metamaterial. A semi-infinite system is also simulated numerically to validate the analytical results and show the band structure for different quasiperiodic patterns, load resistors, and electromechanical coupling coefficients. The topological nature of the bandgaps is detailed through an estimation of the integrated density of states. Furthermore, the presence of topological edge modes is determined through numerical simulation of the energy harvested from the system. The results indicate that quasiperiodic metamaterials with electromechanical resonators can be used for effective energy harvesting without changes in the bandgap topology for weak electromechanical coupling.
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Su, Yaxuan, Xiaohui Lin, Rui Huang, and Zhidong Zhou. "Analytical Electromechanical Modeling of Nanoscale Flexoelectric Energy Harvesting." Applied Sciences 9, no. 11 (June 1, 2019): 2273. http://dx.doi.org/10.3390/app9112273.
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With the attention focused on harvesting energy from the ambient environment for nanoscale electronic devices, electromechanical coupling effects in materials have been studied for many potential applications. Flexoelectricity can be observed in all dielectric materials, coupling the strain gradients and polarization, and may lead to strong size-dependent effects at the nanoscale. This paper investigates the flexoelectric energy harvesting under the harmonic mechanical excitation, based on a model similar to the classical Euler–Bernoulli beam theory. The electric Gibbs free energy and the generalized Hamilton’s variational principle for a flexoelectric body are used to derive the coupled governing equations for flexoelectric beams. The closed-form electromechanical expressions are obtained for the steady-state response to the harmonic mechanical excitation in the flexoelectric cantilever beams. The results show that the voltage output, power density, and mechanical vibration response exhibit significant scale effects at the nanoscale. Especially, the output power density for energy harvesting has an optimal value at an intrinsic length scale. This intrinsic length is proportional to the material flexoelectric coefficient. Moreover, it is found that the optimal load resistance for peak power density depends on the beam thickness at the small scale with a critical thickness. Our research indicates that flexoelectric energy harvesting could be a valid alternative to piezoelectric energy harvesting at micro- or nanoscales.
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VELI, Yelda, and Alexandru M. MOREGA. "ELECTROMECHANICAL CONVERTER FOR ENERGY HARVESTING IN MEDICAL APPLICATIONS." ACTUALITĂŢI ŞI PERSPECTIVE ÎN DOMENIUL MAŞINILOR ELECTRICE (ELECTRIC MACHINES, MATERIALS AND DRIVES - PRESENT AND TRENDS) 2021, no. 1 (November 19, 2021): 1–7. http://dx.doi.org/10.36801/apme.2021.1.11.
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The paper analyzes an electromechanical converter used to collect the mechanical energy provided by the field of deformation of the walls of an arterial vessel as a result of the pulsating flow of blood through it. The structure of the converter is based on the flow of a strong electrically conductive fluid through channels in the magnetic field provided by the permanent magnets placed concentrically along the device and the arterial vessel, the electric field occurring at the electrodes. Numerical analysis neglects the electrical conductivity of the blood. The device has a wide range of applicability and can be adapted to meet industry requirements.
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Smolar, Nejc, and Peter Virtič. "Design investigation of electromechanical generator for energy harvesting." E3S Web of Conferences 116 (2019): 00079. http://dx.doi.org/10.1051/e3sconf/201911600079.
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In this paper designs of electromechanical generator for low frequency energy harvesting have been investigated. Simulation with finite element method has been conducted in order to determine highest output voltage of simple and robust generator consisting of permanent magnet and windings. In first part round magnets have been used in spherical and cylindrical form, benefiting from their ability to roll through winding with almost no mechanical friction inducing voltage in into windings. In the second part spindles with smaller radius than circumference of magnet were added to axis to increase rotational velocity of magnet in ambition to further increase induced voltage. As a result of added spindles and use of different magnet shapes length of winding turn varied and resistance of winding varied with it. To ensure similar conditions, windings have been recalculated to lowest electrical resistance using same fill factor, resulting in less winding turns decreasing induced voltage. In case of same kinetic energy input, higher rotational velocity combined with lower inertia produced higher induced voltage output.
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Liu, Fei, Alex Phipps, Stephen Horowitz, Khai Ngo, Louis Cattafesta, Toshikazu Nishida, and Mark Sheplak. "Acoustic energy harvesting using an electromechanical Helmholtz resonator." Journal of the Acoustical Society of America 123, no. 4 (April 2008): 1983–90. http://dx.doi.org/10.1121/1.2839000.
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Luo, Zhenhua, Dibin Zhu, and Steve Beeby. "An electromechanical model of ferroelectret for energy harvesting." Smart Materials and Structures 25, no. 4 (March 14, 2016): 045010. http://dx.doi.org/10.1088/0964-1726/25/4/045010.
Full textDissertations / Theses on the topic "Electromechanical harvesting"
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Nagode, Clement Michel Jean. "Electromechanical Suspension-based Energy Harvesting Systems for Railroad Applications." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/50611.
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Currently, in the railroad industry, the lack of electrical sources in freight cars is a problem that has yet to find practical solutions. Although the locomotive generates electricity to power the traction motors and all the equipment required to operate the train, the electrical power cannot, in a practical manner, be carried out along the length of the train, leaving freight cars unpowered. While this has not been a major issue in the past, there is a strong interest in equipping modern cars with a myriad of devices intended to improve safety, operational efficiency, or health monitoring, using devices such as GPS, active RFID tags, and accelerometers. The implementation of such devices, however, is hindered by the unavailability of electricity. Although ideas such as Timken\'s generator roller bearing or solar panels exist, the railroads have been slow in adopting them for different reasons, including cost, difficulty of implementation, or limited capabilities.The focus of this research is on the development of vibration-based electromechanical energy harvesting systems that would provide electrical power in a freight car. With size and shape similar to conventional shock absorbers, these devices are designed to be placed in parallel with the suspension elements, possibly inside the coil spring, thereby maximizing unutilized space. When the train is in motion, the suspension will accommodate the imperfections of the track, and its relative velocity is used as the input for the harvester, which converts the mechanical energy to useful electrical energy.
Beyond developing energy harvesters for freight railcar primary suspensions, this study explores track wayside and miniature systems that can be deployed for applications other than railcars. The trackside systems can be used in places where electrical energy is not readily available, but where, however, there is a need for it. The miniature systems are useful for applications such as bicycle energy.
Beyond the design and development of the harvesters, an extensive amount of laboratory testing was conducted to evaluate both the amount of electrical power that can be obtained and the reliability of the components when subjected to repeated vibration cycles. Laboratory tests, totaling more than two million cycles, proved that all the components of the harvester can satisfactorily survive the conditions to which they are subjected in the field. The test results also indicate that the harvesters are capable of generating up to 50 Watts at 22 Vrms, using a 10-Ohm resistor with sine wave inputs, and over 30 Watts at peak with replicated suspension displacements, making them suitable to directly power onboard instruments or to trickle charge a battery.
Ph. D.
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Erturk, Alper. "Electromechanical Modeling of Piezoelectric Energy Harvesters." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/29927.
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Vibration-based energy harvesting has been investigated by several researchers over the last decade. The ultimate goal in this research field is to power small electronic components (such as wireless sensors) by using the vibration energy available in their environment. Among the basic transduction mechanisms that can be used for vibration-to-electricity conversion, piezoelectric transduction has received the most attention in the literature. Piezoelectric materials are preferred in energy harvesting due to their large power densities and ease of application. Typically, piezoelectric energy harvesters are cantilevered structures with piezoceramic layers that generate alternating voltage output due to base excitation. This work presents distributed-parameter electromechanical models that can accurately predict the coupled dynamics of piezoelectric energy harvesters. First the issues in the existing models are addressed and the lumped-parameter electromechanical formulation is corrected by introducing a dimensionless correction factor derived from the electromechanically uncoupled distributed-parameter solution. Then the electromechanically coupled closed-form analytical solution is obtained based on the thin-beam theory since piezoelectric energy harvesters are typically thin structures. The multi-mode electromechanical frequency response expressions obtained from the analytical solution are reduced to single-mode expressions for modal vibrations. The analytical solutions for the electromechanically coupled voltage response and vibration response are validated experimentally for various cases. The single-mode analytical equations are then used for deriving closed-form relations for parameter identification and optimization. Asymptotic analyses of the electromechanical frequency response functions are given along with expressions for the short-circuit and the open-circuit resonance frequencies. A simple experimental technique is presented to identify the optimum load resistance using only a single resistor and an open-circuit voltage measurement. A case study is given to compare the power generation performances of commonly used monolithic piezoceramics and novel single crystals with a focus on the effects of plane-stress material constants and mechanical damping. The effects of strain nodes and electrode configuration on piezoelectric energy harvesting are discussed theoretically and demonstrated experimentally. An approximate electromechanical solution using the assumed-modes method is presented and it can be used for modeling of asymmetric and moderately thick energy harvester configurations. Finally, a piezo-magneto-elastic energy harvester is introduced as a non-conventional broadband energy harvester.Ph. D.
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VILLA, SARA MOON. "SOFT POLYMERIC NANOCOMPOSITES FOR ELECTROMECHANICAL CONVERSION." Doctoral thesis, Università degli Studi di Milano, 2022. http://hdl.handle.net/2434/933149.
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Soft electro-mechanical transducers are receiving a widespread interest for both sensing and energy harvesting applications. In the last decade the research on novel nanocomposites based on polymeric nanocomposites has been very active, and many materials with diverse and innovative compositions and architectures have been fabricated and reported. Nevertheless, there are still some critical aspects that affect this research field, in particular for what regards their characterization.
Despite the widespread interest that these smart materials are attracting, the methods commonly used to characterize them are frequently qualitative and unreliable. Moreover, the description of the testing conditions is often incomplete, so that the data cannot be reproduced by other researchers, and the performances of the various materials cannot be compared. The knowledge of these properties is necessary for a complete understanding of the material working principle, for the prediction of its effective properties aimed at optimization purposes, and for the selection of the right material in device applications. In this framework the development of a quantitative and reliable measurement technique is crucial in order to to assess these materials figure of merit, their reliability and reproducibility.
This thesis work is focused on the fabrication and characterization of materials with electro-mechanical conversion capabilities, for applications in both energy harvesting and pressure and strain sensing. Four different kinds of materials were developed and tested, three active materials based on piezoelectric BaTiO3 nanoparticles on different polymeric matrixes, that can be applied both as sensors and as energy harvesters, and a passive material based on a piezoresistive polymer/metal nanocomposite, which can be applied as a strain sensor. For the characterization of such nanocomposites, a custom experimental set-up to measure the piezoelectric coefficients in a wide frequency range was developed and validated.
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Mateu, Sáez Maria Loreto. "Energy harvesting from human passive power." Doctoral thesis, Universitat Politècnica de Catalunya, 2009. http://hdl.handle.net/10803/48637.
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Las tendencias en la tecnología actual permiten la reducción tanto en tamaño como en potencia
consumida de los sistemas digitales complejos. Esta disminución en el tamaño y el consumo da
lugar al concepto de dispositivos portátiles que se integren en la vida pertenencias personales y
cotidianas como ropa, relojes, gafas, etc. La fuente de alimentación es un factor limitante en la
movilidad de los dispositivos portátiles que se ve reducida por la duración de la batería.
Además, debido a los costos y difícil accesibilidad, la sustitución o recarga de las baterías a
menudo no es viable para los dispositivos portátiles integrados en ropa inteligente. Los
dispositivos vestibles están distribuidos en las pertenencias personales y, por tanto, la
recolección de energía del usuario es una alternativa para su alimentación. Dispositivos
vestibles pueden crear, al igual que los sensores de una red de sensores inalámbricos (WSN),
una red de área corporal. El principal objetivo de esta tesis es el estudio de generadores
piezoeléctricos, inductivos y termoeléctricos que recolectan energía del cuerpo humano de
forma pasiva.
El principio físico de un transductor es el mismo independientemente de si la fuente proviene
del entorno o del cuerpo humano. Sin embargo, las limitaciones relacionadas con la baja
tensión, corriente y niveles de frecuencia conllevan nuevos requerimientos que no están
presentes en el caso de la utilización de las fuentes que ofrece el entorno y que suponen el
principal desafío de esta tesis.
El tipo de energía entrada y transductor a utilizar forman un tándem donde la elección de uno
impone el otro. Es importante que las mediciones se realicen diferentes partes del cuerpo
humano, mientras se realizan diferentes actividades físicas para localizar las posiciones y las
actividades que producen más energía. El acoplamiento mecánico entre transductor y cuerpo
humano depende de la ubicación del transductor y la actividad que se realiza. Un diseño
específico, teniendo esto en cuenta puede aumentar más de un 200% la eficiencia del
transductor como se ha demostrado con láminas piezoeléctricas situadas en plantillas de
zapatos.
Se han realizado mediciones de aceleraciones en diferentes partes del cuerpo y diferentes
actividades para cuantificar la cantidad de energía disponible en actividades cotidianas.
Se ha realizado una simulación a nivel de sistema, modelando los elementos de un sistema de
energía autoalimentado. El transductor se ha modelado usando las ecuaciones físicas que lo
describen con el objetivo de incluir la parte mecánica del sistema. Se han utilizado modelos
eléctricos y de comportamiento para el resto de los componentes. De esta manera, el proceso
de diseño de la aplicación en su conjunto (incluyendo la carga y un elemento de
almacenamiento de energía cuando es necesario) se simplifica a la hora de lograr los requisitos
planteados. Obviamente, la carga debe ser un dispositivo de bajo consumo como por ejemplo
un transmisor RF. En este caso, es preferible alimentar la carga de forma discontinua, sin una
batería, como se deduce de los resultados obtenidos mediante simulación. Sin embargo, la
evolución de los transmisores RF de baja potencia puede cambiar esta conclusión en función
sobre todo de la evolución del consumo de energía en stand-by y el tiempo de configuración
para la operación de transmisión.
Se ha deducido a partir del análisis de los generadores inductivos que el análisis en el dominio
temporal permite calcular algunas magnitudes que no están disponibles en el dominio
frecuencial. Por ejemplo, la potencia máxima se puede calcular en el dominio frecuencial, pero
para aplicaciones de recolección de energía es más interesante saber el valor de la energía
recuperada durante un cierto tiempo o la potencia media ya que la potencia generada por las
actividades humanas pueden ser muy discontinua.
Se ha demostrado que los transductores recolectores de energía son capaces de suministrar
alimentación a dispositivos electrónicos de baja potencia, como quedó demostrado con un
transmisor RF alimentado por una termogenerador que emplea el gradiente de temperatura
existente entre el cuerpo humano y el entorno (3-5 K) y que es capaz de realizar medidas y
transmitirlas una vez cada segundoThe trends in technology allow the decrease in both size and power consumption of complex digital systems. This decrease in size and power gives rise to the concept of wearable devices which are integrated in everyday personal belongings like clothes, watch, glasses, et cetera. Power supply is a limiting factor in the mobility of the wearable device which gets restricted to the lifetime of the battery. Furthermore, due to the costs and inaccessible locations, the replacement or recharging of batteries is often not feasible for wearable devices integrated in smart clothes. Wearable devices are devices distributed in personal belongings and thus, an alternative for powering them is to harvest energy from the user. Therefore, the energy can be harvested, distributed and supplied over the human body. Wearable devices can create, like the sensors of a Wireless Sensor Network (WSN), a Body Area Network. A study of piezoelectric, inductive and thermoelectric generators that harvest passive human power is the main objective of this thesis. The physical principle of an energy harvesting generator is obviously the same no matter whether it is employed with an environmental or human body source. Nevertheless, the limitations related to low voltage, current and frequency levels obtained from human body sources bring new requirements to the energy harvesting topic that were not present in the case of the environment sources. This analysis is the motivation for this thesis. The type of input energy and transducer form a tandem since the election of one imposes the other. It is important that measurements are done in different parts of the human body while doing different physical activities to locate which positions and activities produce more energy. The mechanical coupling between the transducer and the human body depends on the location of the transducer and the activity that is done. A specific design taking this into account can increase more than a 200% the efficiency of the transducer as has been demonstrated with piezoelectric films located in the insoles of shoes. Acceleration measurements have been performed in different body locations and different physical activities, in order to quantify the amount of available energy associated with usual human movements. A system-level simulation has been implemented modeling the elements of an energy self-powered system. Physical equations have been used for the transducer in order to include the mechanical part of the system and electrical and behavioral models for the rest of the components. In this way, the process of the design of the complete application (including the load and an energy storage element when it is necessary) is simplified to achieve the expected requirements. Obviously, the load must be a low power consumption device as for example a RF transmitter. In this case, it is preferable to operate it in a discontinuous way without a battery as it is deduced from simulation results obtained. However, the evolution in low power transmission modules can change this conclusion depending mostly on the evolution of the power consumption in stand-by mode and the configuration time in transmission operation. It has been deduced from the analysis of inductive generators that time-domain analysis allows to calculate some magnitudes that are not available in frequency domain. For example, the maximum power can be calculated in frequency domain, but for energy harvesting applications it is more interesting to know the value of the recovered energy during a certain time, or the average power since the power generated by human activities can be highly discontinuous. It has been demonstrated that energy harvesting transducers are able to supply power to present-day low power electronic devices as was demonstrated with a RF transmitter powered by a thermogenerator that employs the temperature gradient between human body and the environment (3-5 K) and that it is able to sense and transmit data once every second.
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ASKARI, MAHMOUD. "Electromechanical Modelling and Analysis of Piezoelectric Smart Structures: Energy Harvesting, Static and Dynamic Problems." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2964794.
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Gater, Brittany L. "The Hydrodynamics and Energetics of Bioinspired Swimming with Undulatory Electromechanical Fins." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78377.
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Biological systems offer novel and efficient solutions to many engineering applications, including marine propulsion. It is of interest to determine how fish interact with the water around them, and how best to utilize the potential their methods offer. A stingray-like fin was chosen for analysis due to the maneuverability and versatility of stingrays.
The stingray fin was modeled in 2D as a sinusoidal wave with an amplitude increasing from zero at the leading edge to a maximum at the trailing edge. Using this model, a parametric study was performed to examine the effects of the fin on surrounding water in computational fluid dynamics (CFD) simulations. The results were analyzed both qualitatively, in terms of the pressure contours on the fin and vorticity in the trailing wake, and quantitatively, in terms of the resultant forces and the mechanical power requirements to actuate the desired fin motion. The average thrust was shown to depend primarily on the relationship between the swimming speed and the frequency and wavelength (which both are directly proportional to the wavespeed of the fin), although amplitude can be used to augment thrust production as well. However, acceleration was shown to significantly correlate with a large variation in lift and moment, as well as with greater power losses.
Using results from the parametric study, the potential for power regeneration was also examined. Relationships between frequency, velocity, drag, and power input were determined using nonlinear regression that explained more than 99.8% of the data. The actuator for a fin was modeled as a single DC motor-shaft system, allowing the combination of the energetic effects of the motor with the fin-fluid system. When combined, even a non-ideal fin model was able to regenerate more power at a given flow speed than was required to swim at the same speed. Even in a more realistic setting, this high proportion of regenerative power suggests that regeneration and energy harvesting could be both feasible and useful in a mission setting.Master of Science
Animals interact with the world much differently than engineered systems, and can offer new and efficient ways to solve engineering problems, including underwater vehicles. To learn how to move an underwater vehicle in an environmentally conscious way, it is useful to study how a fish’s movements affect the manner in which it moves through the water. Through careful study, the principles involved can be implemented for an efficient, low-disturbance underwater vehicle. The particular fish chosen for in-depth study was the stingray, due to its maneuverability and ability to travel close to the seafloor without disturbing the sediment and creatures around it. In this work, computational analysis was performed on a model of a single stingray fin to determine how the motion of the fin affects the water around it, and how the water affects the fin in turn. The results were analyzed both in terms of the wake behind the fin and in terms of how much power was required to make the fin move in a particular way. The speed of the fin motion was found to have the strongest effect in controlling swimming speed, although the lateral motion of the fin also helped with accelerating faster. Additionally, the potential for a robotic stingray fin to harness power from the water around it was examined. Based on results from simulations of the fin, a mathematical model was formulated to relate energy harvesting with the flow speed past the fin. This model was used to determine how worthwhile it was to use energy harvesting. Analysis of the model showed that harvesting energy from the water was quite efficient, and would likely be a worthwhile investment for an exploration mission.
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Abdelkefi, Abdessattar. "Global Nonlinear Analysis of Piezoelectric Energy Harvesting from Ambient and Aeroelastic Vibrations." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/28761.
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Converting vibrations to a usable form of energy has been the topic of many recent investigations.
The ultimate goal is to convert ambient or aeroelastic vibrations to operate low-power consumption devices, such as microelectromechanical systems, heath monitoring
sensors, wireless sensors or replacing small batteries that have a nite life span or would require hard and expensive maintenance. The transduction mechanisms used for transforming
vibrations to electric power include: electromagnetic, electrostatic, and piezoelectric mechanisms. Because it can be used to harvest energy over a wide range of frequencies and because of its ease of application, the piezoelectric option has attracted significant interest.
In this work, we investigate the performance of different types of piezoelectric energy harvesters. The objective is to design and enhance the performance of these harvesters. To this end, distributed-parameter and phenomenological models of these harvesters are developed. Global analysis of these models is then performed using modern methods of nonlinear dynamics. In the first part of this Dissertation, global nonlinear distributed-parameter models
for piezoelectric energy harvesters under direct and parametric excitations are developed.
The method of multiple scales is then used to derive nonlinear forms of the governing equations
and associated boundary conditions, which are used to evaluate their performance and
determine the effects of the nonlinear piezoelectric coefficients on their behavior in terms of softening or hardening.
In the second part, we assess the influence of the linear and nonlinear parameters on the dynamic behavior of a wing-based piezoaeroelastic energy harvester. The system is composed of a rigid airfoil that is constrained to pitch and plunge and supported by linear and nonlinear torsional and flexural springs with a piezoelectric coupling attached to the plunge
degree of freedom. Linear analysis is performed to determine the effects of the linear spring
coefficients and electrical load resistance on the flutter speed. Then, the normal form of the Hopf bifurcation (flutter) is derived to characterize the type of instability and determine the effects of the aerodynamic nonlinearities and the nonlinear coefficients of the springs on the system's stability near the bifurcation. This is useful to characterize the effects of different parameters on the system's output and ensure that subcritical or "catastrophic" bifurcation does not take place. Both linear and nonlinear analyses are then used to design and enhance the performance of these harvesters.
In the last part, the concept of energy harvesting from vortex-induced vibrations of a
circular cylinder is investigated. The power levels that can be generated from these vibrations
and the variations of these levels with the freestream velocity are determined. A mathematical
model that accounts for the coupled lift force, cylinder motion and generated voltage is
presented. Linear analysis of the electromechanical model is performed to determine the effects of the electrical load resistance on the natural frequency of the rigid cylinder and
the onset of the synchronization region. The impacts of the nonlinearities on the cylinder's
response and energy harvesting are then investigated.Ph. D.
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Forester, Sean M. "Energy harvesting for self-powered, ultra-low power microsystems with a focus on vibration-based electromechanical conversion." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep%5FForester.pdf.
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Thesis (M.S. in Computer Science)--Naval Postgraduate School, September 2009.Thesis Advisor(s): Singh, Gurminder ; Gibson, John. "September 2009." Description based on title screen as viewed on November 6, 2009. Author(s) subject terms: Microelectromechanical systems, photovoltaic, piezoelectric, thermocouple, power harvesting, energy scavenging, thermoelectric. Includes bibliographical references (p. 59-65). Also available in print.
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Maiorca, Felice. "Innovative Electromechanical Transduction Mechanisms for Piezoelectric Energy harvesting from Vibration: Toward Micro and Nano Electro-Mechanical Systems." Doctoral thesis, Università di Catania, 2015. http://hdl.handle.net/10761/3949.
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Vibration energy harvesting is one the hottest topics addressed by a big part of the scientific community. A lot of transduction mechanisms have been investigated and designed, based mechanical systems and transduction principles in order to recover energy coming from environmental vibrations. In this work, innovative transduction mechanisms will be described, suitable to harvesting energy from weak random vibrations, to rectifying and multiplying voltages avoiding the use of classic solutions based on diodes. Innovative devices will be introduced, based on nonlinear mechanical systems and piezoelectric transducers; analytical models will be provided and simulation results will be shown. Laboratory prototypes and experiments will be also described. Comparisons between simulations and experiments results will be provided in order to demonstrate the goodness of the proposed approaches. Finally, MEMS technologies suitable with piezoelectric energy harvesting, together with a very simple micro scale prototype, will be introduced as encouraging elements for future miniaturization of the devices.
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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
Books on the topic "Electromechanical harvesting"
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Energy harvesting with piezoelectric and pyroelectric materials. Stafa-Zuerich, Switzerland: Trans Tech Publications, 2011.
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Muensit, Nantakan. Energy Harvesting with Piezoelectric and Pyroelectric Materials. Trans Tech Publications, Limited, 2011.
Find full textBook chapters on the topic "Electromechanical harvesting"
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Badel, Adrien, Fabien Formosa, and Mickaël Lallart. "Electromechanical Transducers." In Micro Energy Harvesting, 27–60. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527672943.ch3.
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Rafique, Sajid. "A Theoretical Analysis of an ‘Electromechanical’ Beam Tuned Mass Damper." In Piezoelectric Vibration Energy Harvesting, 87–121. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-69442-9_5.
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Bowen, Christopher R., Vitaly Yu Topolov, and Hyunsun Alicia Kim. "Electromechanical Coupling Factors and Their Anisotropy in Piezoelectric and Ferroelectric Materials." In Modern Piezoelectric Energy-Harvesting Materials, 23–57. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-29143-7_2.
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Kumar, Deepak, and Roop Pahuja. "Energy Harvesting by Electromechanical System Using Weight Pulses." In Advances in Automation, Signal Processing, Instrumentation, and Control, 2907–15. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-8221-9_272.
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Devine, Timothy A., V. V. N. Sriram Malladi, and Pablo A. Tarazaga. "Electromechanical Impedance Method for Applications in Boundary Condition Replication." In Sensors and Instrumentation, Aircraft/Aerospace, Energy Harvesting & Dynamic Environments Testing, Volume 7, 93–96. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-12676-6_9.
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Vu, Quyen, and Andrey Ronzhin. "A Model of Four-Finger Gripper with a Built-in Vacuum Suction Nozzle for Harvesting Tomatoes." In Proceedings of 14th International Conference on Electromechanics and Robotics “Zavalishin's Readings”, 149–60. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-9267-2_13.
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"Analytical Distributed-Parameter Electromechanical Modeling of Cantilevered Piezoelectric Energy Harvesters." In Piezoelectric Energy Harvesting, 49–96. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119991151.ch3.
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"Appendix H: Electromechanical Lagrange Equations Based on the Extended Hamilton's Principle." In Piezoelectric Energy Harvesting, 381–83. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119991151.app8.
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"Approximate Analytical Distributed-Parameter Electromechanical Modeling of Cantilevered Piezoelectric Energy Harvesters." In Piezoelectric Energy Harvesting, 151–97. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119991151.ch6.
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"Base Excitation Problem for Cantilevered Structures and Correction of the Lumped-Parameter Electromechanical Model." In Piezoelectric Energy Harvesting, 19–48. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119991151.ch2.
Full textConference papers on the topic "Electromechanical harvesting"
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Zhang, Xu-fang, Shun-di Hu, and Horn-sen Tzou. "Electromechanical coupling and energy harvesting of circular rings." In 2011 Symposium on Piezoelectricity, Acoustic Waves, and Device Applications (SPAWDA 2011). IEEE, 2011. http://dx.doi.org/10.1109/spawda.2011.6167301.
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Bukhari, Mohammad A., Feng Qian, Oumar R. Barry, and Lei Zuo. "Effect of Electromechanical Coupling on Locally Resonant Metastructures for Simultaneous Energy Harvesting and Vibration Attenuation Applications." In ASME 2020 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/dscc2020-3176.
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Abstract The study of simultaneous energy harvesting and vibration attenuation has recently been the focus in many acoustic meta-materials investigations. The studies have reported the possibility of harvesting electric power using electromechanical coupling; however, the effect of the electromechanical resonator on the obtained bandgap’s boundaries has not been explored yet. In this paper, we investigate metamaterial coupled to electromechanical resonators to demonstrate the effect of electromechanical coupling on the wave propagation analytically and experimentally. The electromechanical resonator is shunted to an external load resistor to harvest energy. We derive the analytical dispersion curve of the system and show the band structure for different load resistors and electromechanical coupling coefficients. To verify the analytical dispersion relations, we also simulate the system numerically. Furthermore, experiment is carried out to validate the analytical observations. The obtained observations can guide designers in selecting electromechanical resonator parameters for effective energy harvesting from meta-materials.
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Vieira, Wander G. R., Fred Nitzsche, and Carlos De Marqui. "Non-Linear Modeling and Analysis of Composite Helicopter Blade for Piezoelectric Energy Harvesting." In ASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/smasis2012-8112.
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Converting aeroelastic vibrations into electricity for low-power generation has received growing attention over the past few years. Helicopter blades with embedded piezoelectric elements can provide electrical energy to power small electronic components. In this paper, the non-linear modeling and analysis of an electromechanically coupled cantilevered helicopter blade is presented for piezoelectric energy harvesting. A resistive load is considered in the electrical domain of the problem in order to quantify the electrical power output. The non-linear electromechanical model is derived based on the Variational-Asymptotic Method (VAM). The coupled non-linear rotary system is solved in the time-domain. A generalized-α integration method is used to guarantee numerical stability, adding numerical damping at high frequencies. The electromechanical behavior of the coupled rotating blade is investigated for increasing rotating speeds (stiffening effect).
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Krishnaswamy, Arvind, and D. Roy Mahapatra. "Electromechanical fatigue in IPMC under dynamic energy harvesting conditions." In SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, edited by Yoseph Bar-Cohen and Federico Carpi. SPIE, 2011. http://dx.doi.org/10.1117/12.881092.
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Tsutsumino, Takumi, Yuji Suzuki, and Nobuhide Kasagi. "Electromechanical Modeling of Micro Electret Generator for Energy Harvesting." In TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference. IEEE, 2007. http://dx.doi.org/10.1109/sensor.2007.4300267.
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Anton, Steven, and Daniel Inman. "Electromechanical Modeling of a Multifunctional Energy Harvesting Wing Spar." In 52nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2011. http://dx.doi.org/10.2514/6.2011-2004.
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Adly, A. A., and M. A. Adly. "Utilizing electromechanical energy harvesting in vehicle suspension vibration damping." In 2016 IEEE International Conference on Electronics, Circuits and Systems (ICECS). IEEE, 2016. http://dx.doi.org/10.1109/icecs.2016.7841291.
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Arrieta, Andres F., Peter Hagedorn, Alper Erturk, and Daniel J. Inman. "Electromechanical Modelling and Experiments of a Bistable Plate for Nonlinear Energy Harvesting." In ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2010. http://dx.doi.org/10.1115/smasis2010-3710.
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Vibration based energy harvesting has received extensive attention in the engineering community in the past decade. It has been mainly focused on linear electromechanical devices excited close or at resonance, where these systems operate optimally. Although much progress has been achieved in this research direction, real harvesting devices would seldom operate in environment with such idealized conditions. Recently, the idea to use nonlinearity to enhance the performance for energy harvesters has been introduced. Nonlinear devices have been shown to have the potential to operate over a wider band of frequencies and deliver higher power. Bistable composites are a new type of composites exhibiting two stable states so far considered for morphing applications. In this paper, we propose to exploit the nonlinear behaviour of a bistable composite plate with bonded flexible piezoelectric patches to obtain a nonlinear energy harvesting device. The response of the structure is investigated revealing several large amplitude nonlinear phenomena over a wide range of frequencies. Resistor sweeps are conducted for representative dynamic regimes giving the optimal electrical load for each type of oscillations. The observed characteristics give the proposed device the potentiality for broadband energy harvesting.
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Arrieta, Andres F., Tommaso Delpero, and Paolo Ermanni. "Analytical Electromechanical Model of Cantilevered Bi-Stable Composites for Broadband Energy Harvesting." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3137.
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Vibration based energy harvesting has received extensive attention in the engineering community for the past decade thanks to its potential for autonomous powering small electronic devices. For this purpose, linear electromechanical devices converting mechanical to useful electrical energy have been extensively investigated. Such systems operate optimally when excited close to or at resonance, however, for these lightly damped structures small variations in the ambient vibration frequency results in a rapid reduction of performance. The idea to use nonlinearity to obtain large amplitude response in a wider frequency range, has shown the potential for achieving so called broadband energy harvesting. An interesting type of nonlinear structures exhibiting the desired broadband response characteristics are bi-stable composites. The bi-stable nature of these composites allows for designing several ranges of wide band large amplitude oscillations, from which high power can be harvested. In this paper, an analytical electromechanical model of cantilevered piezoelectric bi-stable composites for broadband harvesting is presented. The model allows to calculate the modal characteristics, such as natural frequencies and mode shapes, providing a tool for the design of bi-stable composites as harvesting devices. The generalised coupling coefficient is used to select the positioning of piezoelectric elements on the composites for maximising the conversion energy. The modal response of a test specimen is obtained and compared to theoretical results showing good agreement, thus validating the model.
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Yoon, Heonjun, Byeng D. Youn, and Heung S. Kim. "Analysis of Electromechanical Performance of Energy Harvesting Skin Based on the Kirchhoff Plate Theory." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-35433.
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As a compact and durable design concept, energy harvesting skin (EH skin), which consists of piezoelectric patches directly attached onto the surface of a vibrating structure as one embodiment, has been recently proposed. This study aims at developing an electromechanically-coupled analytical model of the EH skin so as to understand its electromechanical behavior and get physical insights about important design considerations. Based on the Kirchhoff plate theory, the Hamilton’s principle is used to derive the differential equations of motion. The Rayleigh-Ritz method is implemented to calculate the natural frequency and the corresponding mode shapes of the EH skin. The electrical circuit equation is derived by substituting the piezoelectric constitutive relation into Gauss’s law. Finally, the steady-state output voltage is obtained by solving the differential equations of motion and electrical circuit equation simultaneously. The results of the analytical model are verified by comparing those of the finite element analysis (FEA) in a hierarchical manner.
Reports on the topic "Electromechanical harvesting"
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Zhang, Qiming, and Heath Hogmann. Harvesting Electric Energy During Walking With a Backpack: Physiological, Ergonomic, Biomechanical, and Electromechanical Materials, Devices, and System Considerations. Fort Belvoir, VA: Defense Technical Information Center, January 2005. http://dx.doi.org/10.21236/ada428873.
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