Figure 2 - available via license: CC BY
Content may be subject to copyright.
Principle of operation and alignment of coils and additional magnets. Interior view of the system in a plane perpendicular to the axis of rotation of the pendulum. The system could be fixed to the moving frame with an additional constant tilting angle.
Source publication
A concept of non-linear electromagnetic system with the rotational magnetic pendulum for energy harvesting from mechanical vibrations was presented. The system was stimulated by vertical excitation coming from a shaker. The main assumption of the system was the montage of additional regulated stationary magnets inside coils creating double potentia...
Contexts in source publication
Context 1
... system's design provide to apply versatile coils connection, exemplary connecting 6 coils mounted on one wall of the system. Inside 4 of them, additional adjustable permanent magnets are installed, two of them on each side of the system (Figure 2). They will have an influence on electromagnetic induction of the system and movement of the pendulum by creating double potential well. ...
Context 2
... I-moment of inertia of pendulum, c-damping coefficient, h-distance from center of gravity to pivot axis, m-mass of pendulum and rotational additional masses, g-gravitation, ω-angular velocity of pendulum, A-amplitude of vertical excitation, F mag -magnetic force amplitude acting on pendulum, ϕ-tilt angle of pendulum. The phase shift of 1.5 rad present in the magnetic force term denotes the tilting of the pendulum (Figure 2). Here, we simplified the angular dependence of the magnetic force using sinusoidal dependence. ...
Context 3
... selected features of the Hamiltonian version of the considered model together with the separatrices which defines the regions of two basic solutions: oscillations and rotations are presented in Figure 9a-c. Note that the double well potential (Figure 9c) is generated by the interaction between the pendulum tip permanent magnet and additional permanent magnets distributed in the system as presented in Figure 2. In the studied system the magnetic forces are much stronger than gravity, which leads to a small splitting of the separatrices (see the differences of red and black lines in Figure 9b). ...
Context 4
... phase shift of 1.5 rad present in the magnetic force term denotes the tilting of the pendulum (Figure 2). Here, we simplified the angular dependence of the magnetic force using sinusoidal dependence. ...
Context 5
... selected features of the Hamiltonian version of the considered model together with the separatrices which defines the regions of two basic solutions: oscillations and rotations are presented in Figure 9a-c. Note that the double well potential (Figure 9c) is generated by the interaction between the pendulum tip permanent magnet and additional permanent magnets distributed in the system as presented in Figure 2. In the studied system the magnetic forces are much stronger than gravity, which leads to a small splitting of the separatrices (see the differences of red and black lines in Figure 9b). ...
Similar publications
Ambient vibration energy is widely being harnessed as a source of electrical energy to drive low-power devices. The vibration energy harvester (VEH) of interest employs an electromagnetic transduction mechanism, whereby ambient mechanical vibration is converted to electrical energy. The limitations affecting the performance of VEHs, with an electro...
Citations
... Many devices have been developed by researchers based on the abovementioned energy sources. In this research work, we focused on energy conversion from ambient mechanical vibrations using a pendulum-like rotating body with modifications possible in the system's potential [7]. ...
... Referring to the study on electromagnetic energy harvesters using rotational movement [7], we propose a rotational pendulum concept with an improved approximation. The originality of this system is the variable potential introduced by the pairs of additional adjustable magnets whose strength can be changed. ...
... In our analysis, we studied the magnetic interactions and the dynamics of a system using the FEA and mathematical models. In our previous work [7], the effect on performance was analyzed through magnetic interactions with a simplified FEA model. In this study, the effect of magnet positioning on potential modulation and on attaining complete rotational response is explored using numerical simulations. ...
The proposed energy harvesting system is based on a rotational pendulum-like electromagnetic device. Pendulum energy harvesting systems can be used to generate power for wearable devices such as smart watches and fitness trackers, by harnessing the energy from the human body motion. These systems can also be used to power low-energy-consuming sensors and monitoring devices in industrial settings where consistent ambient vibrations are present, enabling continuous operation without any need for frequent battery replacements. The pendulum-based energy harvester presented in this work was equipped with additional adjustable permanent magnets placed inside the induction coils, governing the movement of the pendulum. This research pioneers a novel electromagnetic energy harvester design that offers customizable potential configurations. Such a design was realized using the 3D printing method for enhanced precision, and analyzed using the finite element method (FEM). The reduced dynamic model was derived for a real-size device and FEM-based simulations were carried out to estimate the distribution and interaction of the magnetic field. Dynamic simulations were performed for the selected magnet configurations of the system. Power output analyses are presented for systems with and without the additional magnets inside the coils. The primary outcome of this research demonstrates the importance of optimization of geometric configuration. Such an optimization was exercised here by strategically choosing the size and positioning of the magnets, which significantly enhanced energy harvesting performance by facilitating easier passage of the pendulum through magnetic barriers.
... To analyze the potential energy distribution, the magnetic interaction force was calculated by FEM software. Ambrozkiewicz et al. [27] established a rotating magnetic pendulum nonlinear electromagnetic system for vibration energy harvester, where the FEM was utilized to model the magnetic flux distribution and the magnetic force under different magnet position configurations. Li et al. [28] proposed an electromagnetic vibration energy harvester based on an eccentric pendulum and optimized the width and thickness of the coils with the goal of maximum power by FEM. ...
... When the voltage output becomes very large, the overall power output becomes disadvantageous due to the increased resistance of the coil. 49 The resistance increases with the number of turns. The same is true in planar coils, which in turn reduces the output power. ...
Social progress is inseparable from the utilization of energy, signals of extreme consumption of fossil energy and energy crisis appear frequently around the world. Human beings are paying more and more attention to new technologies and the sustainable development of energy collection and conversion. The emergence of piezoelectric, electromagnetic, electrostatic, and triboelectric mechanisms provides a variety of effective methods for new environmental energy collection and conversion technologies. Among them, the piezoelectric–electromagnetic hybrid energy harvester (P-EHEH) has been widely studied due to its high output power, simple structure, and easy miniaturization. Continuous progress has been made in the research of P-EHEH through theoretical exploration, structural optimization, and performance improvement. This Review focuses on the review of P-EHEH at the application level. A detailed introduction summarizes the research status of P-EHEH applied to human body devices, monitoring sensors, and power supply devices, as well as the development status of back-end electronic modules and interface circuits. The future challenges and development prospects of P-EHEH are anticipated.
... This increases public knowledge of ambient energies and creates a sizable market for them as potential sources to replace chemical batteries in these devices [1]. Using renewable energy sources, such as solar energy [2], radio frequency (RF) [3], thermal energy [4], and mechanical vibration energy [5], the principle of energy harvesting provides a way to power small devices. Mechanical vibrations occur naturally at low frequencies, as do ambient energies in our surroundings such as wind [6,7], ocean waves [8], human and vehicle movement [9,10], and working equipment, which has frequencies between 1 and 200 Hz [11]. ...
Energy harvesting effectively powers micro-sensors and wireless applications. However, higher frequency oscillations do not overlap with ambient vibrations, and low power can be harvested. This paper utilizes vibro-impact triboelectric energy harvesting for frequency up-conversion. Two magnetically coupled cantilever beams with low and high natural frequencies are used. The two beams have identical tip magnets at the same polarity. A triboelectric energy harvester is integrated with the high-frequency beam to generate an electrical signal via contact-separation impact motion between the triboelectric layers. An electrical signal is generated at the low-frequency beam range achieving frequency up-converter. The two degrees of freedom (2DOF) lumped-parameter model system is used to investigate the system's dynamic behavior and the corresponding voltage signal. The static analysis of the system revealed a threshold distance of 15 mm that divides the system into monostable and bistable regimes. In the monostable and bistable regimes, softening and hardening behaviors were observed at low frequencies. Additionally, the threshold voltage generated was increased by 1117% in comparison with the monostable regime. The simulation findings were experimentally validated. The study demonstrates the potential of using triboelectric energy harvesting in frequency up-converting applications.
... Vibrational energy, which has a high energy density, is ubiquitous and easy to utilize, and is widely present in transportation, industrial equipment, and biological motion, among others. Vibration energy, being widely present, is a potential source of energy that could be harvested to power sensors [2][3][4]. The production of low-frequency energy harvesters is essential, as the vibration sources in ambient conditions, such as human walking, water flow, heartbeats, wind, or vehicle tires, tend to be in the range of 0-20 Hz [5,6]. ...
Inspired by the two typical movement stages in the wingbeat cycle of a seagull in flight, a bio-inspired bistable wing-flapping energy harvester is proposed in this paper to effectively convert low-frequency, low-amplitude and random vibrations into electricity. The movement process of this harvester is analyzed, and it is found that it can significantly alleviate the shortcomings of stress concentration in previous energy harvester structures. A power-generating beam composed of a 301 steel sheet and a PVDF (polyvinylidene difluoride) piezoelectric sheet with imposed limit constraints is then modeled, tested and evaluated. The energy harvesting performance of the model at low frequencies (1–20 Hz) is experimentally examined, where the maximum open-circuit output voltage of the model reaches 11,500 mV at 18 Hz. With a 47 kΩ external resistance of the circuit, the peak output power of the circuit reaches its maximum state of 0.734 mW (18 Hz). When a full bridge circuit is employed to convert AC to DC, the 470 μF capacitor connected to it reaches 3000 mV at peak voltage after 380 s of charging.
... As the electrets are not stretchable, the structural types combining stretchable SP-DEG and electrets as well as the corresponding application scenarios are limited [51]. Compared with the electrets, the passive energy harvesters, including the piezoelectric generators (PEGs) [52,53], the electromagnetic generators (EMGs) [54,55], etc., are potential alternatives to combine with an SP-DEG due to their structural flexibility. This has been studied in the existing literature. ...
A hybrid piezo-dielectric vibration energy harvester (PDVEH) with a self-priming circuit (SPC) is proposed and explored in this paper for passive vibration energy harvesting without an external power supply. The PDVEH consists of a piezoelectric generator (PEG) and a self-priming dielectric elastomer generator (SP-DEG). The PEG can generate electricity from its attached piezoelectric patch. The SP-DEG combines a vibro-impact DEG (VI DEG) with an improved SPC, which can gain initial charges from the PEG. The SPC then enables the DEG to charge itself using the power generated from the intermittent impacts between the inner sphere and the dielectric elastomer membranes. Hence, passive vibration energy harvesting can be realized through the PDVEH. The operation principles of both the PEG and the SP-DEG are analyzed theoretically, and the corresponding governing equations are derived. The key parameters of the PEG are identified from experimental work, and its dynamic and electrical models are verified. The passive energy harvesting process of the SP-DEG charged by PEG is verified through circuit simulations. Numerical simulations are further conducted to reveal the dynamical and electrical behaviors of the PDVEH under external excitations. It is found that the PDVEH can harvest vibration energy effectively in a low-frequency range (0–7 Hz), and its energy harvesting performance is significantly affected by the amplitude and frequency of the excitation. The maximum output power of 0.12 mW can be achieved through the PDVEH in simulations under a vibration excitation with amplitude 1.0g and frequency 6.6 Hz, showing a potential way to realize DEG-based passive vibration energy harvesting.
... Energy harvesting is a method developed since the beginning of the 21st century to obtain electricity from ambient sources, such as vibration [1,2], rotation [3,4] air flow [5,6], and temperature changes [7]. Various aspects of energy harvesting with respect to the vibration ambient sources are discussed and summarized in reviews [8][9][10]. ...
The basic types of multi-stable energy harvesters are bistable energy harvesting systems (BEH) and tristable energy harvesting systems (TEH). The present investigations focus on the analysis of BEH and TEH systems, where the corresponding depth of the potential well and the width of their characteristics are the same. The efficiency of energy harvesting for TEH and BEH systems assuming similar potential parameters is provided. Providing such parameters allows for reliable formulation of conclusions about the efficiency in both types of systems. These energy harvesting systems are based on permanent magnets and a cantilever beam designed to obtain energy from vibrations. Starting from the bond graphs, we derived the nonlinear equations of motion. Then, we followed the bifurcations along the increasing frequency for both configurations. To identify the character of particular solutions, we estimated their corresponding phase portraits, Poincare sections , and Lyapunov exponents. The selected solutions are associated with their voltage output. The results in this numerical study clearly show that the bistable potential is more efficient for energy harvesting provided the corresponding excitation amplitude is large enough. However, the tristable potential could work better in the limits of low-level and low-frequency excitations.
... In addition to actuation, the applicability of multiphysically coupled materials and devices also includes energy harvesting, where some of the ambient energy is converted into useable electricity for a variety of uses, for instance, remote sensors. Regarding vibrational energy as a source, recent trends have shown that there is a strong interest in tuning potential wells to create nonlinearities in the device ( [8]). ...
Initially triggered more than a decade ago by a fruitful German–Korean collaboration, the International Workshop on Piezoelectric Materials and Applications in Actuators has rapidly reached international levels thanks to a strong community making the conference series one of the most recognized in the field [...]
... Iron core could be employed to enhance the magnetic flux density through the coils [24]. In Fig. 10(b), the second was to arrange magnets on the pendulum body and coils on the fixed boards to form a generator [111,112]. This configuration has the advantage of compact integration, but the coils must be coreless type which is disadvantageous to the magnetic flux density. ...
Vibration energy harvesting is a promising approach to provide wireless sensors and portable electronics with sustainable power by converting ambient kinetic energy into expected electrical energy. As one of the most fundamental mechanical oscillators, pendulums are restored by gravity rather than elastic elements and have drawn a number of research interests in developing vibration energy harvesters in recent years due to their simple and reliable structures. This paper comprehensively reviews the state-of-the-art progress of the pendulum-based energy harvesting. The pendulum mechanisms for energy harvesting such as single-pendulum configurations, multi-pendulum configurations, and pendulums with modulation mechanisms are elaborated and discussed. The integrations of electromagnetic, piezoelectric, triboelectric, and hybrid transducers are characterized and compared. The applications of the pendulums in harvesting energy from ocean wave, vehicle motion, human motion, structural vibration, and flow-induced vibration are reviewed. Finally, the challenging issues and future trends of this technology are summarized based on the progress to date.
... Energy harvesting is a process in which energy is collected and stored as electric energy. This energy can come from solar, 1 heat, 2 wind, 3 hydro, 4 mechanical vibrations, 5 and electromagnetic [6][7][8] sources. It can be used to feed several devices such as wireless autonomous devices and sensors. ...
Electromagnetic (EM) RF (radio frequency) energy harvesting in dynamic ambient environments is a challenge for conventional energy harvesting systems such as rectennas. The main challenges are the low efficiency of the collector and low ambient power levels, which makes it hard to consider in industrial applications. Several research works have focused on the design of high-efficiency antennas to achieve an efficient and maximum possible level of RF EM energy harvesting. Their main objective is to improve the EM energy harvesting system by overcoming the low efficiency of the collector, which is the main part of the rectenna system. In this work, we propose and investigate a methodology in terms of EM energy harvesting based on the concentration and focusing of EM energy in a small zone where it can be easily collected and transferred indirectly to the rectenna system. It consists of a focusing device and a methodology to associate the latter with existing RF energy harvesting systems. We demonstrate a focusing metasurface design implemented alongside an off-the-shelf rectenna device at 900 MHz, where an enhanced energy harvested power level up to a linear gain of 8 is achieved compared to the case when only the rectenna is used. Numerical results as well as measurements results in an anechoic chamber are shown. Experimental power received levels are given both in the focusing plane and in time for the validation of the concept.
