The Experts below are selected from a list of 97299 Experts worldwide ranked by ideXlab platform
Sen Li - One of the best experts on this subject based on the ideXlab platform.
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a piezoelectric spring Pendulum oscillator used for multi directional and ultra low frequency vibration energy harvesting
Applied Energy, 2018Co-Authors: Yipeng Wu, Shengpeng Zhou, Hongli Ji, Yang Chen, Sen LiAbstract:Abstract Low frequency vibration is a ubiquitous energy existing in our environment, but a large efficient harvesting of which remains challenging. This paper presents a simple piezoelectric spring architecture based on a common binder clip structure. The harvester with Pendulum spring allows the energy of the dynamic mass to be converted into electrical energy in the piezoelectric transducer. Due to the basic characteristics of spring Pendulums, the proposed harvester can efficiently scavenge not only ultra-low frequency but also multi-directional vibrational energies. Modeling and design are conducted and a normalized expression of the harvester behavior is given. Chirp and human motion excitations are used to evaluate the proposed harvester’s performances. Simulation and experimental results are in good agreement. The proposed device could generate a high output power (13.29 mW) at a low operating frequency (2.03 Hz), which shows great application prospects in the power supply of wearable products, ocean buoys, etc.
J E Faller - One of the best experts on this subject based on the ideXlab platform.
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a simple Pendulum laser interferometer for determining the gravitational constant
Philosophical Transactions of the Royal Society A, 2014Co-Authors: Harold V Parks, J E FallerAbstract:We present a detailed account of our 2004 experiment to measure the Newtonian constant of gravitation with a suspended laser interferometer. The apparatus consists of two simple Pendulums hanging from a common support. Each Pendulum has a length of 72 cm and their separation is 34 cm. A mirror is embedded in each Pendulum bob, which then in combination form a Fabry–Perot cavity. A laser locked to the cavity measures the change in Pendulum separation as the gravitational field is modulated due to the displacement of four 120 kg tungsten masses.
L.i. Hui - One of the best experts on this subject based on the ideXlab platform.
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Numerical Simulation of the Pendulum System in a Buoy-Pendulum Wave Energy Converter☆
Energy Procedia, 2014Co-Authors: He Hong-zhou, L.i. HuiAbstract:Abstract Sea conditions have a significant impact on the efficiency of wave energy converters (WECs). Based on the buoy-Pendulum WEC presented in the paper, the energy-collection principle of the Pendulum system is described, and the motion response of the Pendulums under three wave conditions is simulated. It is shown that the optimal wave direction for Pendulum system's operation is 45°; the Pendulum is apt to reach balance when wave height is less than 0.6 m. In addition, a method to estimate the average conversion efficiency of the Pendulum system is proposed based on the fitting function software, and the efficiencies under five ideal wave conditions are calculated. The results show that the greater the wave period and the wave height, the lower the collection efficiency of the Pendulum.
Yipeng Wu - One of the best experts on this subject based on the ideXlab platform.
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a piezoelectric spring Pendulum oscillator used for multi directional and ultra low frequency vibration energy harvesting
Applied Energy, 2018Co-Authors: Yipeng Wu, Shengpeng Zhou, Hongli Ji, Yang Chen, Sen LiAbstract:Abstract Low frequency vibration is a ubiquitous energy existing in our environment, but a large efficient harvesting of which remains challenging. This paper presents a simple piezoelectric spring architecture based on a common binder clip structure. The harvester with Pendulum spring allows the energy of the dynamic mass to be converted into electrical energy in the piezoelectric transducer. Due to the basic characteristics of spring Pendulums, the proposed harvester can efficiently scavenge not only ultra-low frequency but also multi-directional vibrational energies. Modeling and design are conducted and a normalized expression of the harvester behavior is given. Chirp and human motion excitations are used to evaluate the proposed harvester’s performances. Simulation and experimental results are in good agreement. The proposed device could generate a high output power (13.29 mW) at a low operating frequency (2.03 Hz), which shows great application prospects in the power supply of wearable products, ocean buoys, etc.
Jaroslav Zapoměl - One of the best experts on this subject based on the ideXlab platform.
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Dynamics of a non-autonomous double Pendulum model forced by biharmonic excitation with soft stops
Nonlinear Dynamics, 2020Co-Authors: Marek Lampart, Jaroslav ZapomělAbstract:Pendulums and similar systems, such as links of chains, bodies hanging on ropes, kinematic chains forming working parts of manipulators, and robotic devices, are frequently used in industrial applications. They often cooperate in tubes or working spaces limited by walls or other rigid obstacles. This was the inspiration to carry out this study on the influence of impacts on the behaviour of a chain-like system represented by a double Pendulum moving between two vertical walls. The simulations were performed for a specified extent of excitation frequencies. The results indicate a number of bifurcations that change the character of the induced motion to regular, quasi-periodic, and chaotic in the individual frequency subintervals.
