Artículos de revistas: "Kinetic energy harvesters"

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Chiu, Min Chie, Ying Chun Chang, Long Jyi Yeh, Chiu Hung Chung y Chen Hsin Chu. "An Experimental Study of Low-Frequency Vibration-Based Electromagnetic Energy Harvesters Used while Walking". Advanced Materials Research 918 (abril de 2014): 106–14. http://dx.doi.org/10.4028/www.scientific.net/amr.918.106.

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The goal of this paper is to develop and experimentally test portable vibration-based electromagnetic energy harvesters which are fit for extracting low frequency kinetic energy. Based on a previous study on fixed vibration-based electromagnetic energy harvesters, three kinds of portable energy harvesters (prototype I, prototype II, and prototype III) are developed and tested. To obtain the related parameters of the energy harvesters, an experimental platform used to measure the vibrational systems electrical power at the resonant frequency and other fixed frequencies is also established. Based on the research work of vibration theory, a low frequency vibration-arm mechanism (prototype III) which is easily in resonance with a walking tempo is developed. Here, a strong magnet fixed to one side of the vibration-arm along with a set of wires placed along the vibrating path will generate electricity. The circular device has a radius of 180 mm, a width of 50 mm, and weighs 200 grams. Because of its light mass, it is easy to carry and put into a backpack. Experimental results reveal that the energy harvester (prototype III) can easily transform kinetic energy into electrical power via the vibration-based electromagnetic system when walking at a normal speed. Consequently, electrical energy reaching 0.25 W is generated from the energy harvester (prototype III) by extracting kinetic energy produced by walking.

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Shahosseini, I. y K. Najafi. "Mechanical Amplifier for Translational Kinetic Energy Harvesters". Journal of Physics: Conference Series 557 (27 de noviembre de 2014): 012135. http://dx.doi.org/10.1088/1742-6596/557/1/012135.

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3

Ghaffarinejad, A., Y. Lu, R. Hinchet, D. Galayko, J. Y. Hasani y P. Basset. "Bennet's charge doubler boosting triboelectric kinetic energy harvesters". Journal of Physics: Conference Series 1052 (julio de 2018): 012027. http://dx.doi.org/10.1088/1742-6596/1052/1/012027.

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4

Schaufuss, Joerg, Dirk Scheibner y Jan Mehner. "New approach of frequency tuning for kinetic energy harvesters". Sensors and Actuators A: Physical 171, n.º 2 (noviembre de 2011): 352–60. http://dx.doi.org/10.1016/j.sna.2011.07.022.

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5

Basheer, Faiz, Elmehaisi Mehaisi, Ahmed Elsergany, Ahmed ElSheikh, Mehdi Ghommem y Fehmi Najar. "Energy harvesters for rotating systems: Modeling and performance analysis". tm - Technisches Messen 88, n.º 3 (16 de enero de 2021): 164–77. http://dx.doi.org/10.1515/teme-2020-0088.

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Abstract An exclusive reliance on batteries for miniature sensors has created the need for a self-sustained energy harvester to enable permanent power. This work introduces a pendulum-based energy harvester that is capable of harnessing kinetic energy from rotating structures to generate electric power through electromagnetic transduction. A computational model of the energy harvesting device is developed on Simscape to compute, analyze and compare the power generation capacities of the single, double and Rott’s pendulum systems. Simulation results are validated against their experimental counterparts reported in the literature. Results show an increase in the output voltage in a specific range of rotational speed for all three pendulum harvesters. The double pendulum exhibits the highest power generation potential among the simulated pendulum arrangements. A parametric study revealed that increasing the damping of the harvester decreased its output power, whereas an increase in mass and length of the harvester is observed to increase the output power and shift the optimal power generation subrange.

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6

O’Riordan, Eoghan, Ronan Frizzell, Diarmuid O’Connell y Elena Blokhina. "Characterisation of anti-resonance in two-degree-of-freedom electromagnetic kinetic energy harvester, with modified electromagnetic model". Journal of Intelligent Material Systems and Structures 29, n.º 10 (28 de marzo de 2018): 2295–306. http://dx.doi.org/10.1177/1045389x18758934.

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This article presents a detailed approach to the analysis of a two-degree-of-freedom electromagnetic kinetic energy harvester. These systems use multiple disconnected masses that can impact each other and the harvester housing. This causes complex dynamics in the system as significant momentum is transferred between the masses and, ultimately, results in strongly nonlinear behaviour. One particular nonlinear phenomenon of interest, which has not been previously characterised, is anti-resonance. Observing this phenomenon is important as it highlights efficient energy transfer between the masses, and maximising its effect can be used to enhance the harvesters’ overall performance. A range of mathematical techniques are used to better explain the concept of anti-resonance and how it can be used to improve the understanding of the system dynamics. In addition, the widely used model for electromagnetic transduction is amended to give a more precise representation of the transducer force for this embodiment of the kinetic energy harvester. This unique analysis yields a rich modelling approach that can be used to inform future kinetic energy harvester designs by identifying and optimising key design parameters. Comparisons are made with experimental measurements of a two-mass electromagnetic kinetic energy harvester, validating the modelling approach.

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Lu, Zhuang, Quan Wen, Xianming He y Zhiyu Wen. "A Flutter-Based Electromagnetic Wind Energy Harvester: Theory and Experiments". Applied Sciences 9, n.º 22 (11 de noviembre de 2019): 4823. http://dx.doi.org/10.3390/app9224823.

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Wind energy harvesting is a promising way to offer power supply to low-power electronic devices. Miniature wind-induced vibration energy harvesters, which are currently being focused on by researchers in the field, offer the advantages of small volume and simple structure. In this article, an analytical model was proposed for the kinetic analysis of a flutter-based electromagnetic wind energy harvester. As a result, the critical wind speeds of energy harvesters with different magnet positions were predicted. To experimentally verify the analytical predictions and investigate the output performance of the proposed energy harvester, a small wind tunnel was built. The critical wind speeds measured by the experiment were found to be consistent with the predictions. Therefore, the proposed model can be used to predict the critical wind speed of a wind belt type energy harvester. The experimental results also show that placing the magnets near the middle of the membrane can result in lower critical wind speed and higher output performance. The optimized wind energy harvester was found to generate maximum average power of 705 μW at a wind speed of 10 m/s, offering application prospects for the power supply of low-power electronic devices. This work can serve as a reference for the structural design and theoretical analysis of a flutter-based wind energy harvester.

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8

Ibrahima, Dauda Sh, Asan G. A. Muthalif y Tanveer Saleh. "A Piezoelectric Based Energy Harvester with Magnetic Interactions: Modelling and Simulation". Advanced Materials Research 1115 (julio de 2015): 549–54. http://dx.doi.org/10.4028/www.scientific.net/amr.1115.549.

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In recent years, utilizing kinetic energy in mechanical vibrations has become an interesting area of research. This is due to ubiquitous sources of vibration energy, coupled with the ever increasing demands to power wireless sensing electronics and Microelectromechanical (MEMs) devices with low energy requirements. Thus, researchers have ventured into developing different system configurations with the aim of harvesting vibration energy to power these devices. Cantilever beam systems with piezoelectric layer have been used as vibration energy scavengers due to their abilities of converting kinetic energy in vibrating bodies into electrical energy, whereas permanent magnets have been used to improve their performance. The only unresolved challenge is to develop energy harvesters that can produce optimum energy at a wider bandwidth. In this study, a mathematical model of a system of cantilever beams with piezoelectric layers having a magnetic coupled tip mass is proposed. The lumped parameter model of the harvester is developed to estimate the power output of the proposed harvester, and to visualise the effect of magnetic coupled tip mass in widening the frequency bandwidth of the energy harvester. Preliminary Simulation results using MATLAB have however shown the effectiveness of the proposed system.

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9

Neri, Igor, Flavio Travasso, Riccardo Mincigrucci, Helios Vocca, Francesco Orfei y Luca Gammaitoni. "A real vibration database for kinetic energy harvesting application". Journal of Intelligent Material Systems and Structures 23, n.º 18 (6 de mayo de 2012): 2095–101. http://dx.doi.org/10.1177/1045389x12444488.

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In this article, we discuss the project of a vibration signal database for energy harvesting purpose. After a brief description where we present the technologies used to create the database and the procedures to acquire the signals, we show some results obtained using selected environmental noises from the database to characterize nonlinear energy harvesters.

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10

Beach, Christopher y Alexander J. Casson. "Inertial Kinetic Energy Harvesters for Wearables: The Benefits of Energy Harvesting at the Foot". IEEE Access 8 (2020): 208136–48. http://dx.doi.org/10.1109/access.2020.3037952.

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Azam, Huda, Noor Hazrin Hany Mohamad Hanif y Aliza Aini Md Ralib. "MAGNETICALLY INDUCED PIEZOELECTRIC ENERGY HARVESTER VIA HYBRID KINETIC MOTION". IIUM Engineering Journal 20, n.º 1 (1 de junio de 2019): 245–57. http://dx.doi.org/10.31436/iiumej.v20i1.981.

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ABSTRACT: Piezoelectric energy harvesting is a possible breakthrough to reduce the global issue of electronic waste as they can efficiently convert the ambient vibration to the electrical energy without any additional power. This work presents the design and development of a piezoelectric energy harvester that is capable of transforming vibration from ambient sources into electricity. It focuses on a magnetically plucked piezoelectric beam as an alternative to the mechanically induced harvesters, as the latter are subjected to wear and tear. A prototype comprising of a 40 mm PZT-5H piezoelectric beam with a permanent magnet mounted at one end of the beam, as well as a series of permanent magnets of same types attached on an eccentric rotor was developed along with a National Instruments® data acquisition device. Mean output voltages of 2.98 V, 1.76 V and 0.34 V were recorded when the eccentric rotors were slowly rotated at 8.4 rad/s with increasing distances of 5 mm, 7.5 mm and 10 mm respectively, between the magnets on the rotor and the beam. These results have proven that voltage could also be generated by magnetically plucking the piezoelectric beam, and by reducing the distance between magnets, the amount of voltage generated will be higher. The outcome of this work signifies the possibility for implementation of energy harvesters that are capable of powering electronic devices from hybrid kinetic motion, with a reduced risk of equipment fatigue. ABSTRAK: Penjanaan tenaga melalui piezoelektrik adalah satu penemuan terbesar dalam mengurangkan isu global pengurusan sisa elektronik. Ini kerana ia berupaya mengubah getaran persekitaran kepada tenaga elektrik tanpa sebarang tambahan tenaga. Kajian ini berkenaan reka bentuk dan pembangunan penjana tenaga piezoelektrik yang mampu mengubah getaran persekitaran kepada elektrik. Fokus kajian adalah pada penjanaan tenaga secara magnetik dari bilah piezoelektrik sebagai alternatif kepada penjanaan mekanikal, kerana penjanaan tenaga secara mekanikal berisiko tinggi kepada kerosakan alat dalam jangkamasa panjang. Prototaip piezoelektrik PZT-5H yang berukuran 40 mm ini telah dilengkapi magnet kekal pada hujung bilah, serta satu siri magnet kekal jenis sama turut dipasang pada pemutar eksentrik bersama peranti pengambilan data National Instruments®. Secara purata, sebanyak 2.98 V, 1.76 V dan 0.34 V voltan output telah direkodkan ketika pemutar eksentrik berputar perlahan pada 8.4 rad/s dengan jarak tambahan antara magnet pemutar dan bilah piezoelektrik bersamaan 5 mm, 7.5 mm dan 10 mm, masing-masing. Keputusan menunjukkan tenaga dapat dihasilkan dengan cara pemacuan piezoelektrik secara magnetik, dan tenaga yang terhasil akan bertambah dengan pengurangan jarak antara magnet. Hasil kerja menunjukkan tenaga dapat dihasilkan daripada gerakan kinetik hibrid, dengan risiko rendah pada kerosakan alat.

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Wang, Nianying, Ruofeng Han, Changnan Chen, Jiebin Gu y Xinxin Li. "Double-Deck Metal Solenoids 3D Integrated in Silicon Wafer for Kinetic Energy Harvester". Micromachines 12, n.º 1 (12 de enero de 2021): 74. http://dx.doi.org/10.3390/mi12010074.

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A silicon-chip based double-deck three-dimensional (3D) solenoidal electromagnetic (EM) kinetic energy harvester is developed to convert low-frequency (<100 Hz) vibrational energy into electricity with high efficiency. With wafer-level micro electro mechanical systems (MEMS) fabrication to form a metal casting mold and the following casting technique to rapidly (within minutes) fill molten ZnAl alloy into the pre-micromachined silicon mold, the 300-turn solenoid coils (150 turns for either inner solenoid or outer solenoid) are fabricated in silicon wafers for saw dicing into chips. A cylindrical permanent magnet is inserted into a pre-etched channel for sliding upon external vibration, which is surrounded by the solenoids. The size of the harvester chip is as small as 10.58 mm × 2.06 mm × 2.55 mm. The internal resistance of the solenoids is about 17.9 Ω. The maximum peak-to-peak voltage and average power output are measured as 120.4 mV and 43.7 μW. The EM energy harvester shows great improvement in power density, which is 786 μW/cm3 and the normalized power density is 98.3 μW/cm3/g. The EM energy harvester is verified by experiment to be able to generate electricity through various human body movements of walking, running and jumping. The wafer-level fabricated chip-style solenoidal EM harvesters are advantageous in uniform performance, small size and volume applications.

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Nguyen Duy, Vinh y Hyung-Man Kim. "A Study of the Movement, Structural Stability, and Electrical Performance for Harvesting Ocean Kinetic Energy Based on IPMC Material". Processes 8, n.º 6 (27 de mayo de 2020): 641. http://dx.doi.org/10.3390/pr8060641.

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The movement of water in the oceans generates a vast store of kinetic energy, which has led to the development of a wide variety of offshore energy harvesters all over the world. In our energy harvester, we used ionic polymer-metal composites (IPMCs) to convert the ocean energy into electricity. This paper presents a simulated model of an IPMC-based electrochemical kinetic energy harvesting system installed in the ocean and produced using the computational fluid dynamics (CFD) method. The simulation processes focused on the movement and structural stability of the system design in the ocean for the protection of the IPMC module against possible damage, which would directly affect the power output. Furthermore, the experimental tests under real marine conditions were also studied to analyze the electrical harvesting performance of the IPMC system. These results showed that the use of IPMC materials has many advantages as they are soft and durable; as a result, they can respond faster to wave parameters such as frequency, amplitude, and wavelength.

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Cadei, Andrea, Alessandro Dionisi, Emilio Sardini y Mauro Serpelloni. "Kinetic and thermal energy harvesters for implantable medical devices and biomedical autonomous sensors". Measurement Science and Technology 25, n.º 1 (13 de noviembre de 2013): 012003. http://dx.doi.org/10.1088/0957-0233/25/1/012003.

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15

CHANG, Jen-Yuan (James) y Mike GUTIERREZ. "Self-Powered Kinetic Energy Harvesters for Seek-Induced Vibrations in Hard Disk Drives". Journal of Advanced Mechanical Design, Systems, and Manufacturing 4, n.º 1 (2010): 96–106. http://dx.doi.org/10.1299/jamdsm.4.96.

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16

Yu-Jen, Wang, Chuang Tsung-Yi y Yu Jui-Hsin. "Design and kinetic analysis of piezoelectric energy harvesters with self-adjusting resonant frequency". Smart Materials and Structures 26, n.º 9 (14 de agosto de 2017): 095037. http://dx.doi.org/10.1088/1361-665x/aa7ad6.

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17

Huang, Ledeng, Ruishi Wang, Zhenhua Yang y Longhan Xie. "Energy Harvesting Backpacks for Human Load Carriage: Modelling and Performance Evaluation". Electronics 9, n.º 7 (28 de junio de 2020): 1061. http://dx.doi.org/10.3390/electronics9071061.

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In recent years, there has been an increasing demand for portable power sources as people are required to carry more equipment for occupational, military, or recreational purposes. The energy harvesting backpack that moves relative to the human body, could capture kinetic energy from human walking and convert vertical oscillation into the rotational motion of the generators to generate electricity. In our previous work, a light-weight tube-like energy harvester (TL harvester) and a traditional frequency-tuneable backpack-based energy harvester (FT harvester) were proposed. In this paper, we discuss the power generation performance of the two types of energy harvesters and the energy performance of human loaded walking, while carrying energy harvesting backpacks, based on two different spring-mass-damper models. Testing revealed that the electrical power in the experiments showed similar trends to the simulation results, but the calculated electrical power and the net metabolic power were higher than that of the experiments. Moreover, the total cost of harvesting (TCOH), defined as additional metabolic power in watt required to generate 1 W of electrical power, could be negative, which indicated that there is a chance to generate 6.11 W of electricity without increasing the metabolic cost while carrying energy harvesting backpacks.

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18

Rheinländer, Carl C. y Norbert Wehn. "Harvester-aware transient computing: Utilizing the mechanical inertia of kinetic energy harvesters for a proactive frequency-based power loss detection". Integration 75 (noviembre de 2020): 122–30. http://dx.doi.org/10.1016/j.vlsi.2020.06.010.

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O’Riordan, Eoghan, Dimitri Galayko, Philippe Basset y Elena Blokhina. "Complete electromechanical analysis of electrostatic kinetic energy harvesters biased with a continuous conditioning circuit". Sensors and Actuators A: Physical 247 (agosto de 2016): 379–88. http://dx.doi.org/10.1016/j.sna.2016.06.018.

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20

Sokolov, Andrii, Dhiman Mallick, Saibal Roy, Michael Peter Kennedy y Elena Blokhina. "Modelling and Verification of Nonlinear Electromechanical Coupling in Micro-Scale Kinetic Electromagnetic Energy Harvesters". IEEE Transactions on Circuits and Systems I: Regular Papers 67, n.º 2 (febrero de 2020): 565–77. http://dx.doi.org/10.1109/tcsi.2019.2938421.

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21

Zhu, Hongjun, Tao Tang, Huohai Yang, Junlei Wang, Jinze Song y Geng Peng. "The State-of-the-Art Brief Review on Piezoelectric Energy Harvesting from Flow-Induced Vibration". Shock and Vibration 2021 (1 de abril de 2021): 1–19. http://dx.doi.org/10.1155/2021/8861821.

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Flow-induced vibration (FIV) is concerned in a broad range of engineering applications due to its resultant fatigue damage to structures. Nevertheless, such fluid-structure coupling process continuously extracts the kinetic energy from ambient fluid flow, presenting the conversion potential from the mechanical energy to electricity. As the air and water flows are widely encountered in nature, piezoelectric energy harvesters show the advantages in small-scale utilization and self-powered instruments. This paper briefly reviewed the way of energy collection by piezoelectric energy harvesters and the various measures proposed in the literature, which enhance the structural vibration response and hence improve the energy harvesting efficiency. Methods such as irregularity and alteration of cross-section of bluff body, utilization of wake flow and interference, modification and rearrangement of cantilever beams, and introduction of magnetic force are discussed. Finally, some open questions and suggestions are proposed for the future investigation of such renewable energy harvesting mode.

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22

Mösch, Mario, Gerhard Fischerauer y Daniel Hoffmann. "A Self-Adaptive and Self-Sufficient Energy Harvesting System". Sensors 20, n.º 9 (29 de abril de 2020): 2519. http://dx.doi.org/10.3390/s20092519.

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Self-adaptive vibration energy harvesters convert the kinetic energy from vibration sources into electrical energy and continuously adapt their resonance frequency to the vibration frequency. Only when the two frequencies match can the system harvest energy efficiently. The harvesting of vibration sources with a time-variant frequency therefore requires self-adaptive vibration harvesting systems without human intervention. This work presents a self-adaptive energy harvesting system that works completely self-sufficiently. Using magnetic forces, the axial load on a bending beam is changed and thus the resonance frequency is set. The system achieves a relative tuning range of 23% at a center frequency of 36.4 Hz. Within this range, the resonance frequency of the harvester can be set continuously and precisely. With a novel optimized method for frequency measurement and with customized electronics, the system only needs 22 µW to monitor the external vibration frequency and is therefore also suitable for environments with low vibration amplitudes. The system was verified on a vibrational test bench and can easily be tailored to a specific vibration source.

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23

Jasim, Abbas F., Hao Wang, Greg Yesner, Ahmad Safari y Pat Szary. "Performance Analysis of Piezoelectric Energy Harvesting in Pavement: Laboratory Testing and Field Simulation". Transportation Research Record: Journal of the Transportation Research Board 2673, n.º 3 (27 de febrero de 2019): 115–24. http://dx.doi.org/10.1177/0361198119830308.

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This study investigated the energy harvesting performance of a piezoelectric module in asphalt pavements through laboratory testing and multi-physics based simulation. The energy harvester module was assembled with layers of Bridge transducers and tested in the laboratory. A decoupled approach was used to study the interaction between the energy harvester and the surrounding pavement. The effects of embedment location, vehicle speed, and temperature on energy harvesting performance were investigated. The analysis findings indicate that the embedment location and vehicle speed affects the resulted power output of the piezoelectric energy harvesting system. The embedment depth of the energy module affects both the magnitude and frequency of stress pulse on top of the energy module induced by tire loading. On the other hand, higher vehicle speed causes greater loading frequency and thus greater power output; the effect of pavement temperature is negligible. The analysis of total power output before reaching fatigue failure of the energy module can be used to determine the optimum embedment location in the asphalt layer. The proposed energy harvesting system provides great potential to generate green energy from waste kinetic energy in roadway pavements. Field study is recommended to verify these findings with long-term performance monitoring of pavement with embedded energy harvesters.

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Xu, Ye, Sebastian Bader, Michele Magno, Philipp Mayer y Bengt Oelmann. "System Implementation Trade-Offs for Low-Speed Rotational Variable Reluctance Energy Harvesters". Sensors 21, n.º 18 (21 de septiembre de 2021): 6317. http://dx.doi.org/10.3390/s21186317.

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Low-power energy harvesting has been demonstrated as a feasible alternative for the power supply of next-generation smart sensors and IoT end devices. In many cases, the output of kinetic energy harvesters is an alternating current (AC) requiring rectification in order to supply the electronic load. The rectifier design and selection can have a considerable influence on the energy harvesting system performance in terms of extracted output power and conversion losses. This paper presents a quantitative comparison of three passive rectifiers in a low-power, low-voltage electromagnetic energy harvesting sub-system, namely the full-wave bridge rectifier (FWR), the voltage doubler (VD), and the negative voltage converter rectifier (NVC). Based on a variable reluctance energy harvesting system, we investigate each of the rectifiers with respect to their performance and their effect on the overall energy extraction. We conduct experiments under the conditions of a low-speed rotational energy harvesting application with rotational speeds of 5 rpm to 20 rpm, and verify the experiments in an end-to-end energy harvesting evaluation. Two performance metrics—power conversion efficiency (PCE) and power extraction efficiency (PEE)—are obtained from the measurements to evaluate the performance of the system implementation adopting each of the rectifiers. The results show that the FWR with PEEs of 20% at 5 rpm to 40% at 20 rpm has a low performance in comparison to the VD (40–60%) and NVC (20–70%) rectifiers. The VD-based interface circuit demonstrates the best performance under low rotational speeds, whereas the NVC outperforms the VD at higher speeds (>18 rpm). Finally, the end-to-end system evaluation is conducted with a self-powered rpm sensing system, which demonstrates an improved performance with the VD rectifier implementation reaching the system’s maximum sampling rate (40 Hz) at a rotational speed of approximately 15.5 rpm.

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Beeby, Stephen P., Leran Wang, Dibin Zhu, Alex S. Weddell, Geoff V. Merrett, Bernard Stark, Gyorgy Szarka y Bashir M. Al-Hashimi. "A comparison of power output from linear and nonlinear kinetic energy harvesters using real vibration data". Smart Materials and Structures 22, n.º 7 (7 de junio de 2013): 075022. http://dx.doi.org/10.1088/0964-1726/22/7/075022.

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Rubes, Ondrej, Zdenek Machu, Oldrich Sevecek y Zdenek Hadas. "Crack Protective Layered Architecture of Lead-Free Piezoelectric Energy Harvester in Bistable Configuration". Sensors 20, n.º 20 (14 de octubre de 2020): 5808. http://dx.doi.org/10.3390/s20205808.

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Kinetic piezoelectric energy harvesters are used to power up ultra-low power devices without batteries as an alternative and eco-friendly source of energy. This paper deals with a novel design of a lead-free multilayer energy harvester based on BaTiO3 ceramics. This material is very brittle and might be cracked in small amplitudes of oscillations. However, the main aim of our development is the design of a crack protective layered architecture that protects an energy harvesting device in very high amplitudes of oscillations. This architecture is described and optimized for chosen geometry and the resulted one degree of freedom coupled electromechanical model is derived. This model could be used in bistable configuration and the model is extended about the nonlinear stiffness produced by auxiliary magnets. The complex bistable vibration energy harvester is simulated to predict operation in a wide range of frequency excitation. It should demonstrate typical operation of designed beam and a stress intensity factor was calculated for layers. The whole system, without presence of cracks, was simulated with an excitation acceleration of amplitude up to 1g. The maximal obtained power was around 2 mW at the frequency around 40 Hz with a maximal tip displacement 7.5 mm. The maximal operating amplitude of this novel design was calculated around 10 mm which is 10-times higher than without protective layers.

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Gallardo-Vega, Carlos, Octavio López-Lagunes, Omar I. Nava-Galindo, Arxel De León, Jorge Romero-García, Luz Antonio Aguilera-Cortés, Jaime Martínez-Castillo y Agustín L. Herrera-May. "Triboelectric Energy Harvester Based on Stainless Steel/MoS2 and PET/ITO/PDMS for Potential Smart Healthcare Devices". Nanomaterials 11, n.º 6 (10 de junio de 2021): 1533. http://dx.doi.org/10.3390/nano11061533.

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The smart healthcare devices connected with the internet of things (IoT) for medical services can obtain physiological data of risk patients and communicate these data in real-time to doctors and hospitals. These devices require power sources with a sufficient lifetime to supply them energy, limiting the conventional electrochemical batteries. Additionally, these batteries may contain toxic materials that damage the health of patients and environment. An alternative solution to gradually substitute these electrochemical batteries is the development of triboelectric energy harvesters (TEHs), which can convert the kinetic energy of ambient into electrical energy. Here, we present the fabrication of a TEH formed by a stainless steel substrate (25 mm × 15 mm) coated with a molybdenum disulfide (MoS2) film as top element and a polydimethylsiloxane (PDMS) film deposited on indium tin oxide coated polyethylene terephthalate substrate (PET/ITO). This TEH has a generated maximum voltage of 2.3 V and maximum output power of 112.55 μW using a load resistance of 47 kΩ and a mechanical vibration to 59.7 Hz. The proposed TEH could be used to power potential smart healthcare devices.

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Zheng, Guang Ping, Z. Han y Y. Z. Liu. "The Microstructural, Mechanical and Electro-Mechanical Properties of Graphene Aerogel-PVDF Nanoporous Composites". Journal of Nano Research 29 (diciembre de 2014): 1–6. http://dx.doi.org/10.4028/www.scientific.net/jnanor.29.1.

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Graphene aerogel-poly (vinylidene fluoride) (GA-PVDF) nanoporous composites with different concentrations of PVDF are fabricated. Scanning electron microscopy reveals that PVDF films with a typical thickness below 100 nm are coated at the graphene sheets in the nanoporous composites. The GA-PVDF composites show excellent compressibility, ductility and mechanical strength, as well as better sensitivity of stress-dependent electrical resistance compared with those of GAs. The improved mechanical and electro-mechanical behaviours of nanoporous composites are ascribed to the PVDF which possesses piezoelectricity. The structural properties of the graphene-PVDF nanosized hybrid scaffolds are analyzed by dynamical mechanical relaxation. The results demonstrate that the nanoporous composites could be used as high-performance sensors, actuators and kinetic energy harvesters.

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Ham, Seong Su, Gyoung-Ja Lee, Dong Yeol Hyeon, Yeon-gyu Kim, Yeong-won Lim, Min-Ku Lee, Jin-Ju Park et al. "Kinetic motion sensors based on flexible and lead-free hybrid piezoelectric composite energy harvesters with nanowires-embedded electrodes for detecting articular movements". Composites Part B: Engineering 212 (mayo de 2021): 108705. http://dx.doi.org/10.1016/j.compositesb.2021.108705.

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Zabihi, Niloufar y Mohamed Saafi. "Recent Developments in the Energy Harvesting Systems from Road Infrastructures". Sustainability 12, n.º 17 (20 de agosto de 2020): 6738. http://dx.doi.org/10.3390/su12176738.

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The rapid increase in energy demand has resulted in more dependence on fossil fuels, which leads to higher CO2 emissions every year. To overcome this problem, shifting from fossil fuel-based energy resources to renewable and sustainable ones is essential. One of the new research areas developed in this context is the harvesting of energy from urban infrastructures and, in particular, roads. A large amount of energy in the form of heat or kinetic energy is wasted annually on roads. Recovering these local forms of energy as electricity would improve the energy efficiency of cities. In this review paper, recent developments in the field of energy recovery from roads using solar panels, piezoelectric, thermoelectric and electromagnetic harvesters are discussed along with their efficiency, cost and field implementation. Moreover, new advancements in developing compatible energy storage systems are also discussed and summarised. Based on the review, although all of these systems have the potential of recovering at least a part of the wasted energy, only one of them (the electromagnetic converters) is capable of generating a considerable energy level. In addition, based on the evaluation of the maturity of the technologies, and their cost analyses, more studies are required in order to fill the gap between the current state of the technologies and their full operational form.

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31

Li, Jie Hong, Ming Jing Cai y Long Han Xie. "Develop a Magnetic Pendulum to Scavenge Human Kinetic Energy from Arm Motion". Applied Mechanics and Materials 590 (junio de 2014): 48–52. http://dx.doi.org/10.4028/www.scientific.net/amm.590.48.

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This paper presented a magnetic pendulum to scavenge the human kinetic energy from arm motion and convert the kinetic energy to electrical energy for portable electronic devices. The harvester mainly consisted of a stator, a rotor and a control circuit. The stator was set of electric coils while the rotor is an eccentric mass made of permanent magnet. A torsion spring was also added onto the rotor such that the motions in both horizontal and vertical directions can be effectively harvested. The energy harvester could be worn on human arm. When the arm was in motion, the device would then generate power. The paper presented a detailed kinematical analysis and power conversion analysis. As a typical case, the device was 40 mm in diameter and 50 g in weight, the simulation showed that when worn on wrist, it could generate about 30 mW during normal walking.

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32

Aouali, Kaouthar, Najib Kacem, Noureddine Bouhaddi y Mohamed Haddar. "On the Optimization of a Multimodal Electromagnetic Vibration Energy Harvester Using Mode Localization and Nonlinear Dynamics". Actuators 10, n.º 2 (30 de enero de 2021): 25. http://dx.doi.org/10.3390/act10020025.

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In this paper we study a generic model of a nonlinear quasiperiodic vibration energy harvester (VEH) based on electromagnetic transduction. The proposed device consists of multiple moving magnets guided by elastic beams and coupled by repulsive magnetic forces. A system of two degrees-of-freedom (DOFs) with tunable nonlinearity and mode localization is experimentally validated. The validated 2-DOFs harvester is optimized using a multiobjective optimization procedure to improve its harvested power and frequency bandwidth. An efficient criterion using the modal kinetic energy of the finite element model is proposed to quantify the energy localized in the structure perturbed zones. Afterward, this concept has been generalized to a 5-DOFs VEH with two perturbed DOFs oscillators and the optimal performances are derived using a multiobjective optimization. This proposed model enables a significant increase in the harvested power and frequency bandwidth by 101% and 79%, respectively, compared to that of the 2-DOFs device. Moreover, it has been shown that harvesting energy from two perturbed magnets among five provides almost the same amount of harvested energy and enhances the frequency bandwidth by 18% compared to those of the periodic system. Consequently, the harvester can be improved by reducing the transduction circuits number and the manufacturing cost.

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33

Manjarres, Jose y Mauricio Pardo. "An Energy Logger for Kinetic-Powered Wrist-Wearable Systems". Electronics 9, n.º 3 (15 de marzo de 2020): 487. http://dx.doi.org/10.3390/electronics9030487.

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Kinetic energy harvesting is a promising technology towards the development of alternative battery-charging schemes or even self-powered wearable devices that obtain their power supply from human motion. Although there are many developments with schemes that leverage piezoelectric materials and human motion to power devices especially from footsteps, some other body locations like the wrist still need assessment with piezoelectric generators to evaluate their potential of limitations. In this work, we present the results of logging the energy transference from a wrist-worn piezoelectric harvester to a battery in a wearable device. This system is the continuation of our previous work where we implemented the harvester with a resistive load previously tuned to obtain maximum power and assessed the energy harvested during physical activities. Now, we replace the linear load with a charge controller and a Li-ion battery in the same wearable set-up. These new conditions are not optimal for the piezoelectric generator but present a more realistic environment for the kinetic harvester and allows a more precise study of the feasibility of a self-powered system. Tests show that five minutes of activities that involve arm motion can provide between 1.75 mJ and 2.98 mJ of energy, which can represent between 3.6 seconds and 6.2 seconds of additional battery duration. Hence, these results provide an insight of the limitations and challenges remaining in the piezoelectric-based kinetic harvesting field for wearable devices.

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34

CHANG, Jen-Yuan (James). "DVM-04 SELF-POWERED SEEK-INDUCED KINETIC ENERGY HARVESTER IN COMPUTER HARD DISK DRIVES(Drive Mechanisms I,Technical Program of Oral Presentations)". Proceedings of JSME-IIP/ASME-ISPS Joint Conference on Micromechatronics for Information and Precision Equipment : IIP/ISPS joint MIPE 2009 (2009): 169–70. http://dx.doi.org/10.1299/jsmemipe.2009.169.

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35

Narolia, Tejkaran, Vijay K. Gupta y IA Parinov. "Design and experimental study of rotary-type energy harvester". Journal of Intelligent Material Systems and Structures 31, n.º 13 (12 de junio de 2020): 1594–603. http://dx.doi.org/10.1177/1045389x20930085.

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A rotary-type energy harvester for the applications having space restrictions has been designed and developed to harvest the energy from rotary motion system. The rotation kinetic energy is converted into electrical energy through a lead zirconate titanate patch, which is strained by magnetic force. Most of the researchers used d31 mode of the piezoelectric material of such conversion. Some researchers have explored d33 mode harvester with piezo patch along the circumferential direction. In this article, d33 mode of harvesting with radial direction piezo patch has been proposed. Mathematical and finite element models are developed to calculate the harvested energy. The results are experimentally verified. The average output power of 14.48 nW is generated corresponding to the magnetic force of 0.3126 N and rotational speed of 2100 r/min. The results from the mathematical and finite element models are observed to be consistent with the experimental results. Such harvester will be useful for the applications having space limitations such as self-power generation in an artillery shell and rotary projectile.

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36

Na, Yeong-min, Hyun-seok Lee y Jong-kyu Park. "A study on piezoelectric energy harvester using kinetic energy of ocean". Journal of Mechanical Science and Technology 32, n.º 10 (octubre de 2018): 4747–55. http://dx.doi.org/10.1007/s12206-018-0922-1.

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37

Beyaz, Mustafa, Hacene Baelhadj, Sahar Habibiabad, Shyam Adhikari, Hossein Davoodi y Vlad Badilita. "A Non-Resonant Kinetic Energy Harvester for Bioimplantable Applications". Micromachines 9, n.º 5 (5 de mayo de 2018): 217. http://dx.doi.org/10.3390/mi9050217.

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38

Lee, Chibum y Hee Jae Park. "Design of Optimal Kinetic Energy Harvester Using Double Pendulum". Journal of the Korean Society of Manufacturing Technology Engineers 24, n.º 6 (15 de diciembre de 2015): 619–24. http://dx.doi.org/10.7735/ksmte.2015.24.6.619.

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39

Zeng, Peng y Alireza Khaligh. "A Permanent-Magnet Linear Motion Driven Kinetic Energy Harvester". IEEE Transactions on Industrial Electronics 60, n.º 12 (diciembre de 2013): 5737–46. http://dx.doi.org/10.1109/tie.2012.2229674.

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40

Zeng, Shan, Chunwei Zhang, Kaifa Wang, Baolin Wang y Li Sun. "Analysis of delamination of unimorph cantilever piezoelectric energy harvesters". Journal of Intelligent Material Systems and Structures 29, n.º 9 (14 de febrero de 2018): 1875–83. http://dx.doi.org/10.1177/1045389x17754273.

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Unimorph piezoelectric energy harvesters are typically a unimorph cantilever beam located on a vibrating host structure. Delamination is one of the major failure modes of such unimorph cantilevers and therefore is studied in this article. The delaminated cantilever unimorph is modeled with one through-width crack using four Euler beams connected at delamination edges. The governing equations, the corresponding boundary conditions, and the kinematic continuity conditions are derived based on the Hamiltonian principle. The solutions of the voltage and power output for the present model are derived. The influence of the position and the length of the delamination, frequency of input base excitation, and load resistance on the voltage and power output are discussed in detail. The results show that delamination in the unimorph of the energy harvester will impressively decrease the voltage and power outputs. Influences of the delamination located at the free end of the cantilever are more obvious. For a given active length of the delaminated cantilever energy harvester, it is useful to increase the overall length of the cantilever to obtain a higher voltage and power outputs.

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41

Song, Jiayang y Kean C. Aw. "An energy harvester from human vibrational kinetic energy for wearable biomedical devices". International Journal of Biomechatronics and Biomedical Robotics 3, n.º 1 (2014): 54. http://dx.doi.org/10.1504/ijbbr.2014.059281.

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42

Kwon, Dae-Sung, Hee-Jin Ko, Min-Ook Kim, Yongkeun Oh, Jaesam Sim, Kyounghoon Lee, Kyung-Ho Cho y Jongbaeg Kim. "Piezoelectric energy harvester converting strain energy into kinetic energy for extremely low frequency operation". Applied Physics Letters 104, n.º 11 (17 de marzo de 2014): 113904. http://dx.doi.org/10.1063/1.4869130.

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43

Ayala-Garcia, I. N., P. D. Mitcheson, E. M. Yeatman, D. Zhu, J. Tudor y S. P. Beeby. "Magnetic tuning of a kinetic energy harvester using variable reluctance". Sensors and Actuators A: Physical 189 (enero de 2013): 266–75. http://dx.doi.org/10.1016/j.sna.2012.11.004.

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44

Kumar, Mithlesh, G. M. A. Murali Krishna, Banibrata Mukherjee y Siddhartha Sen. "Design of SOI MEMS-based Bennet’s doubler kinetic energy harvester". Journal of Micro/Nanolithography, MEMS, and MOEMS 19, n.º 01 (20 de febrero de 2020): 1. http://dx.doi.org/10.1117/1.jmm.19.1.015001.

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45

Ayala-Garcia, I. N., D. Zhu, M. J. Tudor y S. P. Beeby. "A tunable kinetic energy harvester with dynamic over range protection". Smart Materials and Structures 19, n.º 11 (21 de septiembre de 2010): 115005. http://dx.doi.org/10.1088/0964-1726/19/11/115005.

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46

Machů, Zdeněk, Oldřich Ševeček, Zdeněk Hadaš y Michal Kotoul. "Modeling of electromechanical response and fracture resistance of multilayer piezoelectric energy harvester with residual stresses". Journal of Intelligent Material Systems and Structures 31, n.º 19 (30 de julio de 2020): 2261–87. http://dx.doi.org/10.1177/1045389x20942832.

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The article focuses on a modeling and subsequent optimization of a novel layered architecture of the vibration piezoceramic energy harvester composed of ZrO2/Al2O3/BaTiO3 layers and containing thermal residual stresses. The developed analytical/numerical model allows to determine the complete electromechanical response and the apparent fracture toughness of the multilayer vibration energy harvester, upon consideration of thermal residual stresses and time-harmonic kinematic excitation. The derived model uses the Euler–Bernoulli beam theory, Hamilton’s variational principle, and a classical laminate theory to determine the first natural frequency, steady-state electromechanical response of the beam upon harmonic vibrations, and also the mechanical stresses within particular layers of the harvester. The laminate apparent fracture toughness is computed by means of the weight function approach. A crucial point is the further optimization of the layered architecture from both the electromechanical response and the fracture resistance point of view. Maximal allowable excitation acceleration of the harvester upon which the piezoelectric layer will not fail is determined. It makes possible to better use the harvester’s capabilities in a given application and simultaneously guarantee its safe operation. Outputs of the derived analytical model were validated with finite element method simulations and available experimental results, and a good agreement between all approaches was obtained.

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47

Kim, In-Ho, Seon-Jun Jang, Shi-Baek Park, Hyung-Jo Jung y Young-Cheol Kim. "Tunable yo-yo energy harvester with oblique springs". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, n.º 16 (25 de marzo de 2020): 3185–94. http://dx.doi.org/10.1177/0954406220913593.

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In this study, a yo-yo vibrational energy harvesting device that can adjust its resonant frequency to the desired excitation frequency using geometrical control is proposed and investigated. The device employs a spring system, suspended proof mass, and set of reels and gears to convert translational input into rotational motion to power its generator. The spring system is composed of two symmetrical oblique springs, and its stiffness and the resonant frequency of the proposed harvester varies with the oblique angle between these springs. The characteristics of the oblique spring system are investigated accordingly, and it is shown that there exists a lower limit of stiffness; therefore, the achievable frequency bandwidth of the harvester can be determined. The method used to design the proposed tunable energy harvester so that it satisfies the desired frequency bandwidth is then provided. A prototype of the device was built and tested on a vibration table, and its performance is illustrated via a comparison with the results of numerical calculations. The results indicate that the proposed device is capable of harnessing the kinetic energy of the ocean waves.

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48

Litak, Grzegorz, Jerzy Margielewicz, Damian Gąska, Piotr Wolszczak y Shengxi Zhou. "Multiple Solutions of the Tristable Energy Harvester". Energies 14, n.º 5 (26 de febrero de 2021): 1284. http://dx.doi.org/10.3390/en14051284.

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This paper presents the results of numerical simulations of a non-linear, tristable system for harvesting energy from vibrating mechanical devices. Detailed model tests were carried out in relation to the system consisting of a beam and three permanent magnets. Based on the derived mathematical model and assuming a range of control parameter variability, a three-dimensional image of the distribution of the largest Lyapunov exponent was plotted. On its basis, the regions of chaotic and predictable movement of the considered system exist have been established. With reference to selected plane of the largest Lyapunov exponent cross-sections, possible co-existing solutions were identified. To identify multiple solutions, a diagram of solutions (DS) diagram was used to illustrate the number of existing solutions and their periodicity. The proposed calculation tool is based on the so-called fixed points of Poincaré cross-section. In relation to selected values of the control parameter ω, coexisting periodic solutions were identified for which phase trajectories and basins of attraction were presented. Based on the model tests carried out, it was found that in order to efficiently harvest energy, appropriate transducer adjustment is required. Calibration of the transducer is necessary to obtain the greatest amplitude of vibration of the beam, which corresponds to the phase trajectory limited by external energy potential barriers. As expected, the average voltage induced on the electrodes of the piezoelectric transducer and the average electrical power recorded on the resistive element are directly proportional to the amplitude and average kinetic energy of the beam.

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49

Van Herbruggen, Ben, Jaron Fontaine, Anniek Eerdekens, Margot Deruyck, Wout Joseph y Eli De Poorter. "Feasibility of Wireless Horse Monitoring Using a Kinetic Energy Harvester Model". Electronics 9, n.º 10 (20 de octubre de 2020): 1730. http://dx.doi.org/10.3390/electronics9101730.

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To detect behavioral anomalies (disease/injuries), 24 h monitoring of horses each day is increasingly important. To this end, recent advances in machine learning have used accelerometer data to improve the efficiency of practice sessions and for early detection of health problems. However, current devices are limited in operational lifetime due to the need to manually replace batteries. To remedy this, we investigated the possibilities to power the wireless radio with a vibrational piezoelectric energy harvester at the leg (or in the hoof) of the horse, allowing perpetual monitoring devices. This paper reports the average power that can be delivered to the node by energy harvesting for four different natural gaits of the horse: stand, walking, trot and canter, based on an existing model for a velocity-damped resonant generator (VDRG). To this end, 33 accelerometer datasets were collected over 4.5 h from six horses during different activities. Based on these measurements, a vibrational energy harvester model was calculated that can provide up to 64.04 μW during the energetic canter gait, taking an energy conversion rate of 60% into account. Most energy is provided during canter in the forward direction of the horse. The downwards direction is less suitable for power harvesting. Additionally, different wireless technologies are considered to realize perpetual wireless data sensing. During horse training sessions, BLE allows continues data transmissions (one packet every 0.04 s during canter), whereas IEEE 802.15.4 and UWB technologies are better suited for continuous horse monitoring during less energetic states due to their lower sleep current.

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50

Wu, Shuai, P. C. K. Luk, Chunfang Li, Xiangyu Zhao y Zongxia Jiao. "Investigation of an Electromagnetic Wearable Resonance Kinetic Energy Harvester With Ferrofluid". IEEE Transactions on Magnetics 53, n.º 9 (septiembre de 2017): 1–6. http://dx.doi.org/10.1109/tmag.2017.2714621.

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