Journal articles: '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.

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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.

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Xue, Xiaomin, Qing Sun, Qiangli Ma, and Jiajia Wang. "A Versatile Model for Describing Energy Harvesting Characteristics of Composite-Laminated Piezoelectric Cantilever Patches." Sensors 22, no. 12 (June 13, 2022): 4457. http://dx.doi.org/10.3390/s22124457.

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Vibration-based energy harvesters consisting of a laminated piezoelectric cantilever have recently attracted attention for their potential applications. Current studies have mostly focused on the harvesting capacity of piezoelectric harvesters under various conditions, and have given less attention to the electromechanical characteristics that are, in fact, crucial to a deeper understanding of the intrinsic mechanism of piezoelectric harvesting. In addition, the current related models have mostly been suitable for harvesting systems with very specific parameters and have not been applicable if the parameters were vague or unknown. Drawing on the available background information, in this study, we conduct research on a vibration-based cantilever beam of composite-laminated piezoelectric patches through an experimental study of its characteristics as well as a modeling study of energy harvesting. In the experimental study, we set out to investigate the harvesting capacity of the system, as well as the electromechanical (voltage/current-strain and power-strain relationships) characteristics of the cantilever harvester. In addition, we summarize some pivotal rules with regard to several design variables, which provide configuration design suggestions for maximizing energy conversion of this type of harvesting system. In the modeling study, we propose a coupled electromechanical model with a set of updated parameters by using an optimization program. The preceding experimental data are used to verify the superiority of the model for accurately predicting the amount of harvested energy, while effectively imitating the characteristics of a cantilever harvesters. The model also has merit since it is suitable for diversified harvesters with vague or even unknown parameters, which cannot be dealt with by using traditional modeling methods. Overall, the experimental study provides information on a comprehensive way to enhance the harvesting capacity of piezoelectric cantilever transducers, and the modeling study provides a wide scope of applications for cantilever harvesters even if precise information is lacking.

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Zhang, Linli, Gaetan Kerschen, and Li Cheng. "Electromechanical Coupling and Energy Conversion in a PZT-Coated Acoustic Black Hole Beam." International Journal of Applied Mechanics 12, no. 08 (September 2020): 2050095. http://dx.doi.org/10.1142/s1758825120500957.

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The phenomenon of acoustic black hole (ABH) exhibits unique and appealing features when bending waves propagate along a structure with a tailored power-law thickness profile. The ABH-induced wave retarding and energy focussing are conducive to effective wave manipulation and energy harvesting. Using a PZT-coated ABH beam as a benchmark, this paper investigates the electromechanical coupling between the PZT patches and the host beam and explores the resultant energy conversion efficiency for potential energy-harvesting (EH) applications. An improved semi-analytical model, considering the full coupling among various electromechanical components in the system, is proposed based on Timoshenko deformation assumption and validated through comparisons with FEM and experimental results. Numerical analyses are then conducted to show typical ABH-specific features as well as the influence of the PZT layout on the electromechanical coupling of the system and the corresponding EH efficiency. Results show that ABH effects entail effective and broadband EH upon proper design of the system with due consideration of the PZT layout in relation to the wavelength and frequency range. Some design guidelines on the installation of PZTs are provided in view of maximization of the ABH benefits and the energy-harvesting performance.

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Tsai, Bor Jang, and Jung Chi Wang. "Rotation Energy Harvesting Device." Applied Mechanics and Materials 548-549 (April 2014): 895–900. http://dx.doi.org/10.4028/www.scientific.net/amm.548-549.895.

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An innovative approach to energy harvesting is to integrate the capture of fragmented energy with micro-electromechanical system (MEMS) to achieve the power self-sufficiency needed for the circuit to function as an autonomous system. This study used a micro-motor as a micro-generator for capturing not only fragmented energy, but also instantaneous energy. The experimental results confirm that energy can be captured from uncollected daily rotational mechanical energy with sufficiently high efficiency and low cost to replace the conventional battery power used in wireless sensors. Applications of this technology in green buildings can not only reduce the energy wasted by wiring, but can also improve internal aesthetics.

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Tol, Serife. "Electromechanical metastructures for simultaneous wave attenuation and energy harvesting." Journal of the Acoustical Society of America 151, no. 4 (April 2022): A156. http://dx.doi.org/10.1121/10.0010957.

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Periodic architectures designed with piezoelectric materials are favorable due to their potential to control waves without any need for structural modifications and also due to their multifunctional abilities, such as energy harvesting and vibration mitigation. This talk focuses on the latter and introduces a piezoelectric-based metastructure with broadband capability of low-frequency elastic wave energy conversion. Unlike the phononic crystal concepts consisting of piezoelectric patch arrays with heavy masses or resonance-based piezoelectric cantilever harvester arrays with tip mass attachments used for harvesting standing waves, our goal is to exploit the properties of locally-resonant metamaterials and phononic crystals within the same structure and harvest energy from travelling elastic waves. Specifically, we merge locally resonant and Bragg band gaps to achieve a multifunctional metastructure, which is capable for maximum energy conversion and wave attenuation in a broadband fashion. To this end, we develop a new wave-based fully coupled electroelastic transfer matrix method and study multifunctional harvesting and attenuation performance of the electromechanical metastructure. The theoretical frameworks and the applicability of the proposed metastructure are also validated using a full-scale experimental setup.

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Kok, B. C., Saleh Gareh, H. H. Goh, and C. Uttraphan. "Electromechanical-Traffic Model of Compression-Based Piezoelectric Energy Harvesting." MATEC Web of Conferences 70 (2016): 10007. http://dx.doi.org/10.1051/matecconf/20167010007.

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Kim, Da Bin, Kwan Hyun Park, and Yong Soo Cho. "Origin of high piezoelectricity of inorganic halide perovskite thin films and their electromechanical energy-harvesting and physiological current-sensing characteristics." Energy & Environmental Science 13, no. 7 (2020): 2077–86. http://dx.doi.org/10.1039/c9ee03212f.

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Sun, Chun Hua, Yong Kang Zhang, Jian Hong Du, and Guang Qing Shang. "Electromechanical Analysis of Piezoelectric Harvesting Unit from Road Vibration with FEA." Advanced Materials Research 726-731 (August 2013): 3144–47. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.3144.

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The purpose of this paper is to analyze the electromechanical properties of piezoelectric harvesting unit from road vibration. A new kind of piezoelectric harvesting unit, which consists of 8 pieces of PZT vibrators and sizes of 280*280*20mm, is purposed. The vibrators are connected and covered by epoxy resin. With the software of ANSYS, open circuit voltage and stress distribution of the unit under the function of vehicle tire pressure are analyzed. The results show that the maximums of open circuit voltage and stress distribution are proportional with the tire pressure. When the tire pressure is 1.0MPa, open circuit voltage and the maximum stress generated by the piezoelectric unit are 950.8V and 9.8MPa, respectively. It means that application of the piezoelectric harvesting unit can couple with the asphalt pavement very well and harvest higher electricity from road vibration on larger area.

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Dwivedi, Ankur, Arnab Banerjee, Sondipon Adhikari, and Bishakh Bhattacharya. "Optimal electromechanical bandgaps in piezo-embedded mechanical metamaterials." International Journal of Mechanics and Materials in Design 17, no. 2 (February 13, 2021): 419–39. http://dx.doi.org/10.1007/s10999-021-09534-0.

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AbstractElastic mechanical metamaterials are the exemplar of periodic structures. These are artificially designed structures having idiosyncratic physical properties like negative mass and negative Young’s modulus in specific frequency ranges. These extreme physical properties are due to the spatial periodicity of mechanical unit cells, which exhibit local resonance. That is why scientists are researching the dynamics of these structures for decades. This unusual dynamic behavior is frequency contingent, which modulates wave propagation through these structures. Locally resonant units in the designed metamaterial facilitate bandgap formation virtually at any frequency for wavelengths much higher than the lattice length of a unit. Here, we analyze the band structure of piezo-embedded negative mass metamaterial using the generalized Bloch theorem. For a finite number of the metamaterial units coupled equation of motion of the system is deduced, considering purely resistive and shunted inductor energy harvesting circuits. Successively, the voltage and power produced by piezoelectric material along with transmissibility of the system are computed using the backward substitution method. The addition of the piezoelectric material at the resonating unit increases the complexity of the solution. The results elucidate, the insertion of the piezoelectric material in the resonating unit provides better tunability in the band structure for simultaneous energy harvesting and vibration attenuation. Non-dimensional analysis of the system gives physical parameters that govern the formation of mechanical and electromechanical bandgaps. Optimized numerical values of these system parameters are also found for maximum first attenuation bandwidth. Thus, broader bandgap generation enhances vibration attenuation, and energy harvesting can be simultaneously available, making these structures multifunctional. This exploration can be considered as a step towards the active elastic mechanical metamaterials design.

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Chang, Wen Yang, and Cheng Han Yang. "Piezoelectric Harvesting Characteristics of BaTiO₃ Microstructures for Optimal Nanogenerators." Advanced Materials Research 747 (August 2013): 205–9. http://dx.doi.org/10.4028/www.scientific.net/amr.747.205.

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The study investigates piezoelectric harvesting efficiency of BTO microstructures with different structural configurations for electromechanical nanogenerators using FEM simulation. The effects of different BTO structures in same cross-section area are simulated, including the lengths, the heights, array numbers, shapes and harmonic response. The results show that a single-bulk structure of piezoelectric BTO produces less harvesting energy than an array structure in same cross-section area. The harvesting voltages increase with array number increasing. However, the energy harvesting obviously decreases when the array number is over 33. There has lager energy harvesting with a small ratio (Rh) that defined a diameter of BTO cylinder devided by a height of BTO cylinder. In addition, the piezoelectric harvesting based on BTO arrays with a zigzag layer has higher harvesting efficiency.

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Pasharavesh, Abdolreza, MT Ahmadian, and H. Zohoor. "Complex modal analysis and coupled electromechanical simulation of energy harvesting piezoelectric laminated beams." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 7 (June 29, 2018): 2526–37. http://dx.doi.org/10.1177/0954406218784623.

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In this paper, coupled electromechanical behavior of a vibrational energy harvesting system composed of a unimorph piezoelectric laminated beam with a large attached tip mass is investigated. To achieve this goal, first the electromechanically coupled partial differential equations governing the lateral displacement and output voltage of the harvester are extracted through exploiting the Hamilton’s principle. Considering vibration damping due to mechanical to electrical energy conversion, a complex modal analysis is performed to extract the complex eigenfrequencies and eigenfunctions of the system. Furthermore, an exact analytical solution is presented for the system response to the harmonic base excitations, including output voltage and harvested power. To validate the analytical results, at the next step a finite element simulation is conducted through ABAQUS software. To perform a fully-coupled analysis which brings into account the effect of harvesting circuit, user subroutine User-defined Amplitude (UAMP) is utilized to calculate the voltage–current relation and impose the correct electrical charge on the electrodes in each step by monitoring the output voltage of the system at previous time increments. Results of both analytical and numerical simulations are compared for a Micro-Electro-Mechanical Systems (MEMS) harvester as a case study, where a very good agreement is observed between them.

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Santini, Jonatha, Christopher Sugino, Emanuele Riva, and Alper Erturk. "Harnessing rainbow trapping via hybrid electromechanical metastructures for enhanced energy harvesting and vibration attenuation." Journal of Applied Physics 132, no. 6 (August 14, 2022): 064903. http://dx.doi.org/10.1063/5.0090258.

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Rainbow trapping is a phenomenon that enables vibration confinement due to the gradual variation of the wave velocity in space, which is typically achieved by means of locally resonant unit cells. In the context of electromechanical metastructures for energy harvesting, this strategy is employed to improve mechanical-to-electrical energy conversion and thereby to maximize the harvested power. In contrast to structures endowed with either mechanical or electromechanical resonators, we investigate a hybrid configuration that leverages the synergistic interplay between them. We compare numerical results for different grading laws in comparison to prior efforts on the topic, demonstrating enhanced energy harvesting and wideband vibration attenuation capabilities of the hybrid metastructure. We also discuss the formation of grading-induced localized modes and we shed light on the role of the motion of individual resonators on the overall power output increase.

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Šutka, Andris, Kaspars Mālnieks, Artis Linarts, Linards Lapčinskis, Osvalds Verners, and Martin Timusk. "Triboelectric Laminates with Volumetric Electromechanical Response for Mechanical Energy Harvesting." Advanced Materials Technologies 6, no. 8 (June 10, 2021): 2100163. http://dx.doi.org/10.1002/admt.202100163.

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Pérez Moyet, Richard, Joseph Stace, Ahmed Amin, Peter Finkel, and George A. Rossetti. "Non-resonant electromechanical energy harvesting using inter-ferroelectric phase transitions." Applied Physics Letters 107, no. 17 (October 26, 2015): 172901. http://dx.doi.org/10.1063/1.4934591.

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Zhang, Xuhui, Wenjuan Yang, Meng Zuo, Houzhi Tan, Hongwei Fan, Qinghua Mao, and Xiang Wan. "An Arc-shaped Piezoelectric Bistable Vibration Energy Harvester: Modeling and Experiments." Sensors 18, no. 12 (December 17, 2018): 4472. http://dx.doi.org/10.3390/s18124472.

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In order to improve vibration energy harvesting, this paper designs an arc-shaped piezoelectric bistable vibration energy harvester (ABEH). The bistable configuration is achieved by using magnetic coupling, and the nonlinear magnetic force is calculated. Based on Lagrangian equation, piezoelectric theory, Kirchhoff’s law, etc., a complete theoretical model of the presented ABEH is built. The influence of the nonlinear stiffness terms, the electromechanical coupling coefficient, the damping, the distance between magnets, and the load resistance on the dynamic response and the energy harvesting performance of the ABEH is numerically explored. More importantly, experiments are designed to verify the energy harvesting enhancement of the ABEH. Compared with the non-magnet energy harvester, the ABEH has much better energy harvesting performance.

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Diab, D., F. Lefebvre, G. Nassar, N. Smagin, A. Naja, and F. El Omar. "Analytical model for the energy harvesting of a spherical sensor from ambient vibrations." MATEC Web of Conferences 171 (2018): 02006. http://dx.doi.org/10.1051/matecconf/201817102006.

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In this work an analytical model for the energy harvesting of an acoustic spherical sensor has been developed in the context to make it autonomous. Our spherical sensor is composed of two half-spheres of Plexiglas and a piezoelectric ring of PZ26 that can be used as exciter or sensor. For the analytical model, the piezoelectric ring was modeled using two primary modes of vibration: thickness and radial. For each mode, the ring is described by an equivalent electromechanical model which connects the mechanical part (forces and velocities) to the electrical part (voltage and current). The proposed paper theoretical model enables building a global electromechanical circuit in order to simulate the total harvested voltage response.

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Tohluebaji, Nikruesong, Panu Thainiramit, Chatchai Putson, and Nantakan Muensit. "Phase and Structure Behavior vs. Electromechanical Performance of Electrostrictive P(VDF-HFP)/ZnO Composite Nanofibers." Polymers 13, no. 15 (July 31, 2021): 2565. http://dx.doi.org/10.3390/polym13152565.

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In this work, we improved the electromechanical properties, electrostrictive behavior and energy-harvesting performance of poly(vinylidenefluoridene-hexafluoropropylene) P(VDF-HFP)/zinc oxide (ZnO) composite nanofibers. The main factor in increasing their electromechanical performance and harvesting power based on electrostrictive behavior is an improved coefficient with a modified crystallinity phase and tuning the polarizability of material. These blends were fabricated by using a simple electrospinning method with varied ZnO contents (0, 5, 10, 15 and 20 wt%). The effects of the ZnO nanoparticle size and content on the phase transformation, dielectric permittivity, strain response and vibration energy harvesting were investigated. The characteristics of these structures were evaluated utilizing SEM, EDX, XRD, FT-IR and DMA. The electrical properties of the fabrication samples were examined by LCR meter as a function of the concentration of the ZnO and frequency. The strain response from the electric field was observed by the photonic displacement apparatus and lock-in amplifier along the thickness direction at a low frequency of 1 Hz. Moreover, the energy conversion behavior was determined by an energy-harvesting setup measuring the current induced in the composite nanofibers. The results showed that the ZnO nanoparticles’ component effectively achieves a strain response and the energy-harvesting capabilities of these P(VDF-HFP)/ZnO composites nanofibers. The electrostriction coefficient tended to increase with a higher ZnO content and an increasing dielectric constant. The generated current increased with the ZnO content when the external electric field was applied at a vibration of 20 Hz. Consequently, the ZnO nanoparticles dispersed into electrostrictive P(VDF-HFP) nanofibers, which offer a large power density and excellent efficiency of energy harvesting.

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Sequeira, Dane, Kip Coonley, and Brian Mann. "Topological optimization of variable area plate capacitors for coupled electromechanical energy harvesters." Journal of Intelligent Material Systems and Structures 30, no. 15 (July 12, 2019): 2198–211. http://dx.doi.org/10.1177/1045389x19861792.

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This article examines how topological optimization can be applied to identify nonintuitive capacitor plate patterning that maximizes average power dissipated through an electrical circuit during energy harvesting. Coupled electromechanical equations of motion are derived that include both the instantaneous and change in overlapping conductive area as functions of plate rotation. A genetic algorithm is used to optimize these terms and then map them to physical plate configurations. The results obtained apply specifically to the case presented; however, the methods are general and can be used to solve a broad range of electrostatic energy harvesting problems.

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Guillot, François M., Haskell W. Beckham, and Johannes Leisen. "Hollow Piezoelectric Ceramic Fibers for Energy Harvesting Fabrics." Journal of Engineered Fibers and Fabrics 8, no. 1 (March 2013): 155892501300800. http://dx.doi.org/10.1177/155892501300800109.

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In the past few years, the growing need for alternative power sources has generated considerable interest in the field of energy harvesting. A particularly exciting possibility within that field is the development of fabrics capable of harnessing mechanical energy and delivering electrical power to sensors and wearable devices. This study presents an evaluation of the electromechanical performance of hollow lead zirconate titanate (PZT) fibers as the basis for the construction of such fabrics. The fibers feature individual polymer claddings surrounding electrodes directly deposited onto both inside and outside ceramic surfaces. This configuration optimizes the amount of electrical energy available by placing the electrodes in direct contact with the surface of the material and by maximizing the active piezoelectric volume. Hollow fibers were electroded, encapsulated in a polymer cladding, poled and characterized in terms of their electromechanical properties. They were then glued to a vibrating cantilever beam equipped with a strain gauge, and their energy harvesting performance was measured. It was found that the fibers generated twice as much energy density as commercial state-of-the-art flexible composite sensors. Finally, the influence of the polymer cladding on the strain transmission to the fiber was evaluated. These fibers have the potential to be woven into fabrics that could harvest mechanical energy from the environment and could eventually be integrated into clothing.

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Liu, Huan, Xiujuan Lin, Shuo Zhang, Yu Huan, Shifeng Huang, and Xin Cheng. "Enhanced performance of piezoelectric composite nanogenerator based on gradient porous PZT ceramic structure for energy harvesting." Journal of Materials Chemistry A 8, no. 37 (2020): 19631–40. http://dx.doi.org/10.1039/d0ta03054f.

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Thiam, Amadou G., and Allan D. Pierce. "Electromechanical transduction system design for optimal energy harvesting from ocean waves." Journal of the Acoustical Society of America 130, no. 4 (October 2011): 2504. http://dx.doi.org/10.1121/1.3654975.

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Siddiqui, Naved A., Dong-Joo Kim, Ruel A. Overfelt, and Barton C. Prorok. "Electromechanical coupling effects in tapered piezoelectric bimorphs for vibration energy harvesting." Microsystem Technologies 23, no. 5 (December 30, 2016): 1537–51. http://dx.doi.org/10.1007/s00542-016-3197-4.

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Lien, I. C., Y. C. Lo, S. H. Chiu, and Y. C. Shu. "Comparison between overall and respective electrical rectifications in array of piezoelectric energy harvesting." Journal of Mechanics 38 (2022): 518–30. http://dx.doi.org/10.1093/jom/ufac039.

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Abstract The article compares two different electrical rectifications employed by a piezoelectric harvester array. The first type consists of parallel connection of harvesters followed by an AC–DC full-bridge rectifier for overall electrical rectification. The second type allows for respective electrical rectification of each individual harvester, and then connecting them all in parallel. The former exhibits stronger electromechanical coupling effect for enhancing output power. The latter is capable of avoiding charge cancelation for improving bandwidth. The analysis of the electromechanical response of these two types is provided with full derivations for the second case. The predictions of displacement and output power are compared with the experiment and the results show good agreement. Two recommendations are offered from the present studies. First, suppose the power dissipations due to voltage gaps across the rectifiers are insignificant compared with the amount of output power realized by each individual harvester. The piezoelectric harvester array with respective electrical rectification exhibits better performance than that with the overall rectification from the broadband point of view at the cost of reducing peak power. On the contrary, if the amount of power dissipations can not be neglected or the harvester exhibits the strongly coupled electromechanical response, it is recommended to employ the harvester array allowing the mixed parallel/series connections switched by DPDT (Double-Pole Double-Throw). The array of the mixed type with overall electrical rectification exhibits performance significantly outperforming the array with respective electrical rectification from the point of view of broadband and power enhancement.

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Linh, N. N., V. A. Tuan, N. V. Tuan, and N. D. Anh. "Response analysis of undamped primary system subjected to base excitation with a dynamic vibration absorber integrated with a piezoelectric stack energy harvester." Vietnam Journal of Mechanics 44, no. 4 (December 30, 2022): 490–99. http://dx.doi.org/10.15625/0866-7136/17948.

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Dynamic vibration absorber (DVA) integrated with a piezoelectric stack energy harvesting subjected to base excitation is introduced in this paper. The system of dynamic vibration absorber and piezoelectric stack energy harvesting system (DVA-PSEH) has two functions, the first is to reduce vibrations for the primary system, and the second is to convert a part of the vibrational energy into electricity through the piezoelectric effect. The mechanical and electrical responses of the electromechanical system are determined by the complex amplitude method, then the numerical simulations are carried out to investigate the characteristics of DVA-PSEH.

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Hegendörfer, Andreas, Paul Steinmann, and Julia Mergheim. "Nonlinear finite element system simulation of piezoelectric vibration-based energy harvesters." Journal of Intelligent Material Systems and Structures 33, no. 10 (October 8, 2021): 1292–307. http://dx.doi.org/10.1177/1045389x211048222.

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Piezoelectric vibration-based energy harvesters consist of an electromechanical structure and an electric circuitry, influencing each other. We propose a novel approach that allows a finite element based system simulation of nonlinear electromechanical structures coupled to nonlinear electric circuitries. In the finite element simulation the influence of the electric circuit on the electromechanical structure is considered via the vector of external forces, using an implicit time integration scheme. To demonstrate the applicability of the new simulation method an active power circuit is considered. Several examples of piezoelectric vibration-based energy harvesters, connected to standard or synchronized switch harvesting on inductor (SSHI) circuits, showing linear or nonlinear mechanical behavior, are studied to validate the proposed simulation method against numerical results reported in the literature. The advocated method allows for consistent and efficient simulations of complete nonlinear energy harvesters using only one software tool.

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Yan, Zhen, and Qing He. "A Review of Piezoelectric Vibration Generator for Energy Harvesting." Applied Mechanics and Materials 44-47 (December 2010): 2945–49. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.2945.

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Piezoelectric vibration generator has the advantages of small volume and simple technology and working in various poor environments, so it will inevitably power for wireless sensor network, micro electromechanical system (MEMS) devices, and other electric devices, instead of traditional cell. First of all, the generation power principle as well as the vibration mode of piezoelectric vibration generator is presented. Then, the basic theory and its application of structural behavior and damping influence are analyzed. Finally, the problems and the challenge of piezoelectric vibration generator are discussed.

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Sapiński, Bogdan, and Marcin Węgrzynowski. "EXPERIMENTAL SETUP FOR TESTING ROTARY MR DAMPERS WITH ENERGY HARVESTING CAPABILITY." Acta Mechanica et Automatica 7, no. 4 (December 1, 2013): 241–44. http://dx.doi.org/10.2478/ama-2013-0041.

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Abstract The experimental setup has been developed for laboratory testing of electromechanical energy transducers and rotary magnetorheological (MR) dampers. The design objectives are outlined and the parameters of the key elements of the setup are summarised. The structure of the mechanical and measurement and control systems is presented. Results of functional testing of a newly developed transducer and a MR rotary damper are summarised

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Rosa, Maiara, and Carlos De Marqui Junior. "Modeling and Analysis of a Piezoelectric Energy Harvester with Varying Cross-Sectional Area." Shock and Vibration 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/930503.

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This paper reports on the modeling and on the experimental verification of electromechanically coupled beams with varying cross-sectional area for piezoelectric energy harvesting. The governing equations are formulated using the Rayleigh-Ritz method and Euler-Bernoulli assumptions. A load resistance is considered in the electrical domain for the estimate of the electric power output of each geometric configuration. The model is first verified against the analytical results for a rectangular bimorph with tip mass reported in the literature. The experimental verification of the model is also reported for a tapered bimorph cantilever with tip mass. The effects of varying cross-sectional area and tip mass on the electromechanical behavior of piezoelectric energy harvesters are also discussed. An issue related to the estimation of the optimal load resistance (that gives the maximum power output) on beam shape optimization problems is also discussed.

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Remick, Kevin, D. Dane Quinn, D. Michael McFarland, Lawrence Bergman, and Alexander Vakakis. "High-frequency vibration energy harvesting from repeated impulsive forcing utilizing intentional dynamic instability caused by strong nonlinearity." Journal of Intelligent Material Systems and Structures 28, no. 4 (July 28, 2016): 468–87. http://dx.doi.org/10.1177/1045389x16649699.

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The work in this study explores the excitation of high-frequency dynamic instabilities to enhance the performance of a strongly nonlinear vibration-based energy harvesting system subject to repeated impulsive excitations. These high-fraequency instabilities arise from transient resonance captures (TRCs) in the damped dynamics of the system, leading to large-amplitude oscillations in the mechanical system. Under proper forcing conditions, these high-frequency instabilities can be sustained. The primary system is composed of a grounded, weakly damped linear oscillator, which is directly subjected to impulsive forcing. A light-weight, damped nonlinear oscillator (nonlinear energy sink, NES) is coupled to the primary system using electromechanical coupling elements and strongly nonlinear stiffness elements. The essential (nonlinearizable) stiffness nonlinearity arises from geometric and kinematic effects resulting from the traverse deflection of a piano wire coupling the two oscillators. The electromechanical coupling is composed of a neodymium magnet and inductance coil, which harvests the energy in the mechanical system and transfers it to the electrical system which, in this present case, is composed of a simple resistive element. The energy dissipated in the circuit is inferred as a measure of energy harvesting capability. The large-amplitude TRCs result in strong, nearly irreversible energy transfer from the primary system to the NES, where the harvesting elements work to convert the mechanical energy to electrical energy. The primary goal of this work is to numerically and experimentally demonstrate the efficacy of inducing sustained high-frequency dynamic instability in a system of mechanical oscillators to achieve enhanced vibration energy harvesting performance. This work is a continuation of a companion paper (Remick K, Quinn D, McFarland D, et al. (2015) Journal of Sound and Vibration Final Publication) where vibration energy harvesting of the same system subject to single impulsive excitation is studied.

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Yiming Liu, Geng Tian, Yong Wang, Junhong Lin, Qiming Zhang, and Heath F. Hofmann. "Active Piezoelectric Energy Harvesting: General Principle and Experimental Demonstration." Journal of Intelligent Material Systems and Structures 20, no. 5 (November 28, 2008): 575–85. http://dx.doi.org/10.1177/1045389x08098195.

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In piezoelectric energy harvesting systems, the energy harvesting circuit is the interface between a piezoelectric device and an electrical load. A conventional view of this interface is based on impedance matching concepts. In fact, an energy harvesting circuit can also apply electrical boundary conditions, such as voltage and charge, to the piezoelectric device for each energy conversion cycle. An optimized electrical boundary condition can therefore increase the mechanical energy flow into the device and the energy conversion efficiency of the device. We present a study of active energy harvesting, a type of energy harvesting approach which uses switch-mode power electronics to control the voltage and/or charge on a piezoelectric device relative to the mechanical input for optimized energy conversion. Under quasi-static assumptions, a model based on the electromechanical boundary conditions is established. Some practical limiting factors of active energy harvesting, due to device limitations and the efficiency of the power electronic circuitry, are discussed. In the experimental part of the article, active energy harvesting is demonstrated with a multilayer PVDF polymer device. In these experiments, the active energy harvesting approach increased the harvested energy by a factor of five for the same mechanical displacement compared to an optimized diode rectifier-based circuit.

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Pan, Cheng-Tang, Chung-Kun Yen, Hui-Chun Wu, Liwei Lin, Yi-Syuan Lu, Jacob Chih-Ching Huang, and Shiao-Wei Kuo. "Significant piezoelectric and energy harvesting enhancement of poly(vinylidene fluoride)/polypeptide fiber composites prepared through near-field electrospinning." Journal of Materials Chemistry A 3, no. 13 (2015): 6835–43. http://dx.doi.org/10.1039/c5ta00147a.

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Xiao, Hanjie, Tianrun Li, Liang Zhang, Wei-Hsin Liao, Ting Tan, and Zhimiao Yan. "Metamaterial based piezoelectric acoustic energy harvesting: Electromechanical coupled modeling and experimental validation." Mechanical Systems and Signal Processing 185 (February 2023): 109808. http://dx.doi.org/10.1016/j.ymssp.2022.109808.

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Maruccio, Claudio, Giuseppe Quaranta, and Giuseppe Grassi. "Reduced-order modeling with multiple scales of electromechanical systems for energy harvesting." European Physical Journal Special Topics 228, no. 7 (August 2019): 1605–24. http://dx.doi.org/10.1140/epjst/e2019-800173-x.

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Kefal, Adnan, Claudio Maruccio, Giuseppe Quaranta, and Erkan Oterkus. "Modelling and parameter identification of electromechanical systems for energy harvesting and sensing." Mechanical Systems and Signal Processing 121 (April 2019): 890–912. http://dx.doi.org/10.1016/j.ymssp.2018.10.042.

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Flankl, Michael, Arda Tuysuz, and Johann W. Kolar. "Cogging Torque Shape Optimization of an Integrated Generator for Electromechanical Energy Harvesting." IEEE Transactions on Industrial Electronics 64, no. 12 (December 2017): 9806–14. http://dx.doi.org/10.1109/tie.2017.2733441.

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Cao, Jian-Bo, Shi-Ju E, Zhuang Guo, Zhao Gao, and Han-Pin Luo. "Electromechanical conversion efficiency for dielectric elastomer generator in different energy harvesting cycles." AIP Advances 7, no. 11 (November 2017): 115117. http://dx.doi.org/10.1063/1.5003767.

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Pasharavesh, Abdolreza, M. T. Ahmadian, and H. Zohoor. "Electromechanical modeling and analytical investigation of nonlinearities in energy harvesting piezoelectric beams." International Journal of Mechanics and Materials in Design 13, no. 4 (August 30, 2016): 499–514. http://dx.doi.org/10.1007/s10999-016-9353-2.

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Morel, Adrien, Alexis Brenes, David Gibus, Elie Lefeuvre, Pierre Gasnier, Gaël Pillonnet, and Adrien Badel. "A comparative study of electrical interfaces for tunable piezoelectric vibration energy harvesting." Smart Materials and Structures 31, no. 4 (March 7, 2022): 045016. http://dx.doi.org/10.1088/1361-665x/ac54e8.

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Abstract The present work deals with tunable electrical interfaces able to enhance both the harvested power and bandwidth of piezoelectric vibration energy harvesters. The aim of this paper is to propose a general, normalized, and unified performance evaluation (with respect to the harvested power and bandwidth) of the various electrical strategies that can tune the harvester’s frequency response. By mean of a thorough analysis, we demonstrate how such interfaces influence the electromechanical generator response through an electrically-induced damping and an electrically-induced stiffness. The choice of the strategy determines these two electrical quantities, and thus the achievable frequency response of the system. Thereafter, we introduce a collection of graphical and analytical tools to compare and analyze single- and multi-tuning electrical strategies, including a qualitative performance evaluation of existing strategies. Finally, we establish a unified comparison of single- and multiple-tuning strategies which is supported by the definition and evaluation of a new optimization criterion. This comparison reveals which strategy performs best depending on the electromechanical coupling of the piezoelectric harvester and on the losses in the electrical interface. Furthermore, it quantifies the power and bandwidth gain brought by single- and multi-tuning strategies. Such quantitative criterion provides guidance for the choice of a harvesting strategy in any specific applicative case.

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Brunner, Stephan, Maximilian Gerst, and Christian Pylatiuk. "Design of a body energy harvesting system for the upper extremity." Current Directions in Biomedical Engineering 3, no. 2 (September 7, 2017): 331–34. http://dx.doi.org/10.1515/cdbme-2017-0067.

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AbstractConverting energy from human upper limb motions into electrical energy is a challenge, as low frequency movements have to be converted into repetitive movements to effectively drive electromechanical generators. The prototype of an electromagnetic linear generator with gyrating mass is presented. The mechanical motion model first was simulated and the design was evaluated during different activities. An average power output of about 50 μW was determined with a maximum power output of 2.2 mW that is sufficient to operate sensors for health monitoring.

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Chen, Bing, Jiang Ren, and Kaixuan Ma. "Research on Energy Harvesting of Piezoelectric Vibration Using 2D ABH Structure." Journal of Physics: Conference Series 2186, no. 1 (February 1, 2022): 012013. http://dx.doi.org/10.1088/1742-6596/2186/1/012013.

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Abstract The acoustic black hole (ABH) effect can achieve energy concentration by changing the structural characteristics and reducing the propagation velocity of curved waves. This way of energy gathering provides a new idea for the harvesting of vibration energy. In this study, an energy collection structure with 2D ABH characteristics is proposed and studied, which can effectively provide energy harvesting efficiency. According to the theory of geometric acoustics, the size of the piezoelectric patch is designed to be smaller than the half wavelength of the bending wave at the centre of ABH, so as to avoid the situation of positive and negative charge cancellation caused by multiple bending waves on a single piezoelectric patch, and improve the energy utilization rate. The electromechanical coupling model of 2D ABH structure and piezoelectric energy collection circuit was established to study the energy harvesting performance of the plate with 2D ABH structure under transient and steady state conditions. The results show that the 2D ABH structure can effectively increase the frequency width range of vibration energy harvesting and improve energy harvesting efficiency

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Yabin Liao and Henry A. Sodano. "Structural Effects and Energy Conversion Efficiency of Power Harvesting." Journal of Intelligent Material Systems and Structures 20, no. 5 (November 28, 2008): 505–14. http://dx.doi.org/10.1177/1045389x08099468.

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The concept of power harvesting works towards developing self-powered devices that do not require replaceable power supplies. One important parameter defining the performance of a piezoelectric power harvesting system is the efficiency of the system. However, an accepted definition of energy harvesting efficiency does not currently exist. This article will develop a new definition for the efficiency of an energy harvesting system, which rather than being defined through energy conservation as the ratio of the energy fed into the system to maintain the steady state to the output power, we consider the ratio of the strain energy over each cycle to the power output. This new definition is analogous to the material loss factor. Simulations will be performed to demonstrate the validity of the efficiency and will show that the maximum efficiency occurs at the matched impedance; however, for materials with high electromechanical coupling, the maximum power is generated at the near open- and closed-circuit resonances with a lower efficiency.

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Journal articles on the topic 'Electromechanical harvesting'

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