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(color online) (a) Vibration voltage amplitude normalized to the acceleration (| )|ܽߜ/ܸߜmeasured as a function of the frequency (݂) across a large load resistance (ܴ = 10 GΩ) with different values of a tip proof mass (݉୧୮) in the 50 mm long bidomain LN / spring-steel / metglas cantilever. The inset shows the change in the resonance frequency and peak voltage ratio with the tip mass. (b) Average vibration power ratio (〈ܲ〉/||ܽߜଶ) as a function of the frequency measured for different values of the load resistance in the MME cantilever with the tip permanent magnet. The inset depicts the current- and voltage-to-acceleration ratios at the resonance frequency as a function of the load resistance. (c) Absolute voltage amplitude obtained as a function of the applied acceleration amplitude at ݂ = 100 Hz. The inset shows the voltage normalized to this acceleration.
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With the recent thriving of low-power electronic microdevices and sensors the development of components capable of scavenging environmental energy has become imperative. In this work we studied bidomain congruent LiNbO3 (LN) single crystals combined with magnetic materials for dual, mechanical and magnetic, energy harvesting applications. A simple...
Citations
... Transduction mechanisms of vibration energy harvesting essentially rely on the electromagnetic [44,45,46,47], electrostatic [48], piezoelectric [49,50,51], and triboelectric phenomena [52,53,54,55]. This work is focused on EMGs using magnetic levitation architectures, as those can operate across a wider spectrum of frequency, enabling them to capture energy from either low-frequency or high-frequency oscillations [56,57,58]. ...
... Efficiency can be increased using self-powering sensing, either using a network of low-dimensional outer sensing coils or using piezoelectric sensors to monitor the relative motion between LM and coils. Piezoelectric lead-free materials could be engineered for such purpose, as they can be designed with many different compositions, structures, and desirable properties, exhibiting the ability to provide large output voltages even for low excitation frequencies, and ensuring ease down-scalability [50]. More sophisticated circuitry could be employed to switch the coils between in series and in parallel architectures, such that a dynamically tune of the equivalent internal impedance of the generator can be implemented. ...
The development of self-powering systems has been recognized as critical such that innovative stand-alone emerging technologies can operate sustainably from scavenged ambient energy. Electromagnetic generators (EMGs) using magnetic levitation architectures for mechanical vibration energy harvesting are a promising technology that can be tailored to specific needs and provide low-cost electric powering for both small-scale and large-scale devices. They also present non-complex design, with low maintenance requirements and can operate with stable performance for long periods of time. Despite these prominent features, their complex non-linear and hysteresis-based resonant characteristics makes performance optimization hard to achieve and still needs to be addressed as a function of the input excitation. Numerical and experimental results are here provided to demonstrate the effectiveness of a new concept of EMG that aims to dynamically adapt the coil-array architecture throughout its operation to ensure maximum harvested power and to optimize the transduction mechanism efficiency. The self-adaptive motion-driven levitation-based autonomously rearranges each coil independently as a function of the instantaneous time-varying characteristics of the levitating magnet (LM) position. The mechanism features two dynamic coil switching strategies: (i) on/off switching, by short circuiting, with transmission gate switches, the coils without influence on the electromotive force; and (ii) reversing polarity switching, to avoid the sum of electromotive forces cancels each other. Average output powers of 635 mW (up to ∼4.1 W of peak power) were obtained with only the 4-centre (out of 14) permanently active coils, while only 292 mW (up to 833 mW of peak power) were achieved with the 14-coils permanently connected under optimal load conditions and harmonic translational input excitations with 15 Hz frequency and 20 mm amplitude. However, the adaptive generator was able to provide an impressive average power output of 3 W under the same conditions. Up to 14-fold larger output average power and 5.5-fold larger electric efficiency demonstrate the potential of the proposed coil switching self-adaptation system for enhancing the total energy conversion from general widespread mechanical vibrations.
... Using the above methods one can produce domain structures in crystals with elongated head-to-head or tailto-tail CDW. Depending on the pattern of internal fields, polydomain, bidomain-polydomain or bidomain structures with sharp interdomain boundaries can form [42,43]. Initially, bidomain crystals were suggested for use in piezoelectric mechano-electric converters such as precision actuators [56][57][58][59][60][61][62][63], low-frequency vibration [37] and magnetic field (within composite magnetoelectrics [64]), as well as waste energy harvesters [65][66][67], but the presence of a single CDW with an area of decades of sq.cm makes this material extremely attractive for studying resistive and memristive switching processes. ...
Charged domain walls (CDWs) in ferroelectric materials raise both fundamental and practical interest due to their electrophysical properties differing from bulk ones. On a microstructure level, CDWs in ferroelectrics are 2D defects separating regions with different spontaneous polarization vector directions. Screening of electric field of the CDW's bound ionic charges by mobile carriers leads to the formation of elongated narrow channels with an elevated conductivity in initially dielectric materials. Controlling the position and inclination angle of CDW relative to the spontaneous polarization direction, one can change its conductivity over a wide range thus providing good opportunities for developing memory devices, including neuromorphic systems. This review describes the state of art in the formation and application of CDWs in single crystal uniaxial ferroelectric lithium niobate (LiNbO 3 , LN), as resistive and memristive switching devices. The main CDWs formation methods in single crystal and thin-film LN have been described, and modern data have been presented on the electrophysical properties and electrical conductivity control methods of CDWs. Prospects of CDWs application in resistive and memristive switching memory devices have been discussed.
... The sensor and electrical wires used in the EMI technique should be carefully designed to minimize any discomfort or inconvenience for patients. For example, biocompatible lead-free piezoelectric elements must be used to fabricate the sensor [77,78]. The test should be performed by qualified professionals with patient well-being in mind to ensure patient safety and comfort. ...
Accurate quantification of the jawbone-implant interface plays a pivotal role in assessing the mechanical stability of dental implant structures. This study proposes a methodology integrating the electro-mechanical impedance (EMI)-based technique with a deep learning algorithm to autonomously monitor the bone-implant interface during the osseointegration process. We develop a 1D convolutional neural network (1D CNN) model, which automatically processes raw EMI data and extracts optimal features for predicting osseointegration ratios. To validate our approach, we conduct predictive 3D numerical modelling of the PZT-implant-bone system. This model simulates the implant’s EMI response under varying degrees of osseointegration. Next, we employ traditional statistical metrics to monitor osseointegration and discuss their limitations. Finally, we apply the proposed 1D CNN model to predict bone-implant osseointegration rate. We train and test the network using the simulated EMI data with added noise to account for real-world conditions. The results show that the trained model achieves a minimal testing error of just 2.4%. Even when 60% of testing cases are not trained, the model maintains a prediction accuracy exceeding 94%.
... Using the above methods one can produce domain structures in crystals with elongated head-to-head or tailto-tail CDW. Depending on the pattern of internal fields, polydomain, bidomain-polydomain or bidomain structures with sharp interdomain boundaries can form [42,43]. Initially, bidomain crystals were suggested for use in piezoelectric mechano-electric converters such as precision actuators [56][57][58][59][60][61][62][63], low-frequency vibration [37] and magnetic field (within composite magnetoelectrics [64]), as well as waste energy harvesters [65][66][67], but the presence of a single CDW with an area of decades of sq.cm makes this material extremely attractive for studying resistive and memristive switching processes. ...
Charged domain walls (CDW) in ferroelectric materials are interesting from fundamental and applied points of view, since they have electrical properties different from bulk ones. At the microstructural level, CDW in ferroelectrics are two-dimensional defects that separate regions of the material with different directions of spontaneous polarization vectors. Compensation of the electric field of the bound ionic charge of the CDW by mobile carriers leads to the formation of extended narrow channels with increased conductivity in the original dielectric material. By controlling the position and angle of inclination of the CDW relative to the direction of spontaneous polarization, it is possible to change its conductivity in a wide range, which opens up broad prospects for creating memory devices, including for neuromorphic systems. The review presents the current state of research in the field of formation and application of CDW formed in single crystals of uniaxial ferroelectric lithium niobate (LiNbO 3 , LN) as resistive and memristive switching devices. The main methods for forming CDW in single crystals and thin films of LN are considered, and modern data on the electrophysical properties and methods for controlling the electrical conductivity of CDW are presented. The prospects for using CDW in memory devices with resistive and memristive switching are discussed.
... ME composite systems composed of piezoelectric phases (P) and magnetostrictive phases (M) and possessing strong room temperature ME coupling (high ME conversion efficiency) are drawing considerable interest in the fields of vibration energy and magnetic energy harvesting. [33][34][35][36][37][38][39][40] The magnetostrictive phase induced by the magnetic field in a composite system generates strain (magnetostrictive effect), which is transferred to the piezoelectric phase through interface elastic coupling, thus inducing electric polarization (piezoelectric effect), as illustrated in Figure 1B. Due to the dependence of magnetostrictive strain on the applied magnetic field, an ac magnetic field (H ac ) and a dc bias magnetic field (H dc ) are usually required to trigger the ME coupling effect of such a composite. ...
... Due to the dependence of magnetostrictive strain on the applied magnetic field, an ac magnetic field (H ac ) and a dc bias magnetic field (H dc ) are usually required to trigger the ME coupling effect of such a composite. [31][32][33][34][35][36][37][38][39][40][41][42][43][44] The introduction of H dc often limits the miniaturization and precision of devices due to various drawbacks, such as low signal-to-noise ratio, weak resolution, and large device size. The introduction of a self-bias/zero-bias effect (without a dc magnetic field) into ME composites or structures (self-biased ME coupling effect [SME]) is preferred for developing a large, and tunable ME coupling effect, which will be of great significance for the miniaturization and integration of devices and systems. ...
The wireless sensor network energy supply technology for the Internet of things has progressed substantially, but attempts to provide sustainable and environmentally friendly energy for sensor networks remain limited and considerably cumbersome for practical application. Energy harvesting devices based on the magnetoelectric (ME) coupling effect have promising prospects in the field of self‐powered devices due to their advantages of small size, fast response, and low power consumption. Driven by application requirements, the development of composite with a self‐biased magnetoelectric (SME) coupling effect provides effective strategies for the miniaturized and high‐precision design of energy harvesting devices. This review summarizes the work mechanism, research status, characteristics, and structures of SME composites, with emphasis on the application and development of SME devices for vibration and magnetic energy harvesting. The main challenges and future development directions for the design and implementation of energy harvesting devices based on the SME effect are presented.
... In studies done between 2005 and 2016, PZT piezopolymer transducers outperformed other piezoelectric transducers in performance efficiency throughout a low-frequency range of 50Hz-150Hz. Piezoelectric materials include (a) ceramics [14], (b) piezopolymers [15], and (c) piezomagnetoelastic [16] This section will examine and compare the developments and advancements in the piezoelectric transduction mechanism over the last several years. We would look at the most recent technique, both power production and frequency protection. ...
... Table 3 summarizes the vibration energy harvesting via electrostatic transduction. Fig. 8. Triboelectric nanogenerator (a) 3D triboelectric nanogenerator [31] (b) ferrofluid-based triboelectric-electromagnetic [32] (c) spring based triboelectric nanogenerator [33] (d) honeycomb structure inspired triboelectric nanogenerator [34] [35] 2013 3D spiral triboelectric nanogenerator (TENG) 30 2760 [31] 2014 3D triboelectric nanogenerator (3D-TENG) 75 1350 [36] 2014 3D triboelectric nanogenerator (3D-TENG) 20 0.00128 [37] 2014 Contact-mode triboelectric nanogenerator (CF_TENG) 15 17 [44] 2017 Spring-based amplifier with triboelectric nanogenerator - [32] 2017 Ferrofluid tribo-electric-electromagnetic (FF-TEEM) device 7 - [45] 2018 Triboelectric-piezoelectric-electromagnetic 20 122 [33] 2018 Spring based TENG (S-TENG) 16 (vertical resonance vibration) 8.5 (horizontal resonance vibration) 240 45 [46] 2018 Floating buoy-based triboelectric nanogenerator (FB-TENG) 1.7 0.036 [34] 2019 Honeycomb structure -triboelectric nanogenerator (HSI-TENG) 33 - [47] 2020 Spherical triboelectric nanogenerator 8 0.0000109 A triboelectric nanogenerator is an energy harvesting system that uses the triboelectric effect and electrostatic induction to transform external mechanical energy into electricity. Triboelectric nanogenerator (TENG) as a power source and self-powered sensors have made tremendous development in recent years [47][48][49]. ...
Energy harvesting has been around for more than a decade, with continual research tackling the issues of charging and powering up electronic gadgets. Because of its multiple advantages, such as greater mobility and a longer lifespan, the notion of energy harvesting has acquired broad popularity. Researchers are investigating methods to harness the energy created by vibrations from various materials and transducers as part of the energy conservation movement. This paper examines major advancements in vibration energy collecting during the last 15 years. It focuses on the many processes used to collect vibration energy, such as piezoelectric, electromagnetic, electrostatic generators, and MEMs techniques, as well as power management circuits, to enhance various elements of vibration energy harvesting devices from diverse sources. While the research on vibration energy harvesting has grown significantly, this work summarises significant achievements in the subject over the last 15 years and updates prior review publications.
... Nakamura et al. [26] and Kubasov et al. [27] developed new promising techniques to directly engineer two polarization domains in a single bulk ferroelectric crystal (bidomain), thus excluding any bonded interfaces [28,29]. The absence of an intermediate viscous glue layer between macrodomains results in high thermal stability and linearity of the deformation-to-voltage conversion, which makes them ideal for precise sensing, actuation and energy harvesting [30][31][32][33][34]. We proposed the use of bidomain lithium niobate (b-LN) single crystals [7,[35][36][37] to decrease the operation frequency and partially suppress extrinsic and intrinsic noises in ME composites. ...
Non-contact mapping of magnetic fields produced by the human heart muscle requires the application of arrays of miniature and highly sensitive magnetic field sensors. In this article, we describe a MEMS technology of laminated magnetoelectric heterostructures comprising a thin pie-zoelectric lithium niobate single crystal and a film of magnetostrictive metglas. In the former, a fer-roelectric bidomain structure is created using a technique developed by the authors. A cantilever is formed by microblasting inside the lithium niobate crystal. Metglas layers are deposited by magne-tron sputtering. The quality of the metglas layers was assessed by XPS depth profiling and TEM. Detailed measurements of the magnetoelectric effect in the quasistatic and dynamic modes were performed. The magnetoelectric coefficient |α32| reaches a value of 492 V/(cm·Oe) at bending resonance. The quality factor of the structure was Q = 520. The average phase amounted to 93.4° ± 2.7° for the magnetic field amplitude ranging from 12 to 100 pT. An AC magnetic field detection limit of 12 pT at a resonance frequency of 3065 Hz was achieved which exceeds by a factor of 5 the best value for magnetoelectric MEMS lead-free composites reported in the literature. The noise level of the magnetoelectric signal was 0.47 µV/Hz 1/2. Ways to improve the sensitivity of the developed sensors to the magnetic field for biomedical applications are indicated.
... The rapid development of autonomous wireless sensor networks for various medical, environmental, and engineering applications leads to constantly increasing demand for long-life and low-power energy sources [1][2][3]. Energy harvesting recently arose as a cuttingedge technology for low-cost renewable "green" energy collection from vibrations, friction, temperature, pressure variations, optical irradiation, etc. [4][5][6][7][8][9][10][11][12][13]. Among the numerous harvesting systems suggested so far, the triboelectric nanogenerators (TENGs) collecting energy from the periodic movements proved themselves to be simple, low-cost, and effective for various multiscale applications [13]. ...
Along with piezoelectric nanogenerators, triboelectric nanogenerators (TENGs) collecting energy from mechanical vibrations proved to be simple, low-cost, and efficient sources of electricity for various applications. In view of possible biomedical applications, the search for TENGs made of biomolecular and biocompatible materials is demanding. Diphenylalanine (FF) microstructures are promising for these applications due to their unique characteristics and ability to form various morphologies (microribbons, spherical vesicles, fibrils, micro- and nanotubes, nanorods, etc.). In this work, we developed a contact-separate mode TENG based on arrays of oriented FF microbelts deposited by dip-coating technique and studied their performance under various temperature treatments. We show that these TENGs outperform piezoelectric nanogenerators based on FF microbelts in terms of short-circuit current (ISC), open-circuit voltage (VOC), and output power. It was found that bound water captured in FF nanochannels mainly affects VOC, whereas mobile water increases ISC. We also found that the cyclization of FF molecules increases the performance of TENG likely due to an increase in surface energy and surface flattening.
... This fact introduces complications, namely high maintenance costs and low generation performance, as current non-intermittent energy harvesting systems are not able to carry out adaptation to varying mechanical excitations [15,16]. Various vibration transduction mechanisms have been explored mainly including: piezoelectric (PEGs) [17,18], electromagnetic (EMGs) [1,19], and electrostatic/triboelectric (TENGs) [3,20]. Electromagnetic generators in particular are well established, versatile and scalable from small-to large-scale [20][21][22]. ...
... In greater detail, the output current in the low frequency approximation can be combined with the top equation in (18), resulting in a single second-order ODE with a load dependent EM damping constant equal to (disregarding possible Lorentz forces from farther away short-circuited coils disconnected from the circuit, which are assumed to be comparatively low): ...
Self-powered electronic devices have been widely sought after in the last few years demanding efficient harvesting of locally available forms of energy. Electromagnetic generators are suitable contenders for powering both small-scale and large-scale devices due to their widespread availability and customizability. New promising magnet levitation architectures for mechanical vibration energy harvesting offer low production and maintenance costs, as well as a wide array of designs. They also exhibit complex non-linear and hysteretic resonant behaviors. Nonetheless, their performance is typically optimized towards external excitations with very specific characteristics. In this study, we theoretically and experimentally prove the concept of an instrumented self-adaptive levitation generator with on/off coil switching employing an accelerometer, transmission gate switches and a processing system. This adaptable system is able to periodically turn off coils not contributing to the generated electromotive forces for certain frequencies and amplitudes of the input excitations. Taking the power consumption of instrumentation into account, power gains up to ≈ 26% were achieved for harmonic inputs with randomly time changing frequencies and amplitudes. Using a prototype generator with 140.7 cm³, output average powers of up to 1.79 W (i.e., 12.7 kW/m³) were extracted for optimal electrical loads under non-linear resonant conditions. Significant increases in electric power efficiencies were achieved as well. These promising results should pave the way towards intelligent self-adapting energy generators.
... Many transduction mechanisms have been developed to convert the ubiquitous mechanical energy surrounding us to electric energy, among which one must highlight the piezoelectric [26,27], electromagnetic [1,28], and triboelectric [3,29]. Electromagnetic harvesting is a unique technology because it is scalable from small-to large-scale [29][30][31]. ...
Electromagnetic generators are widely used to power both small-scale and large-scale devices. They are suitable to operate as self-powering technologies, allowing customizable upscaling and downscaling, ensuring low production and maintenance costs, and even able to integrate into hybrid solutions. As their architectures are well-suited to power a broad range of multifunctional devices, their performance optimization is a research topic of utmost importance. Their performance, strongly dependent on the frequency and amplitude of mechanical excitations and hysteretic behaviors, still needs to be improved. In this paper, a theoretical and experimental study is provided to demonstrate the effectiveness of a new concept of self-adaptive electromagnetic generator. An instrumented generator using a magnetic levitation architecture was implemented using a stepper motor, an accelerometer and a processing system. Self-adaptability was realized by changing the generator’s effective length and resonance frequency as a function of the mechanical excitation characteristics. Considering the power consumption of instrumentation, output power gains around 30% were achieved under conditions of harmonic inputs with time changing frequencies and amplitudes. These are very promising results that highlight the potential of self-adaptive energy harvesting technologies for opening new research directions towards the emerging of a new line of highly sophisticated autonomous generators.
