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Development of an Opposed Mass-Spring Type Bi-Stable Vibration Energy Harvesting System Using Stochastic Resonance
Linshi Guo,
Wei Zhao,
Nobuyuki Gomi,
Jingchao Guan,
Xilu Zhao
Issue:
Volume 10, Issue 6, December 2022
Pages:
123-134
Received:
9 October 2022
Accepted:
28 October 2022
Published:
4 November 2022
DOI:
10.11648/j.ijmea.20221006.11
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Abstract: Improving the efficiency of vibration power generation is an important research topic. Therefore, it is effective to develop a vibration power generation system using a bistable vibration model. The bistable vibration model considered in previous studies has the problem that the center of gravity is high and the vibration power generation efficiency is relatively low. In this study, we propose a horizontally opposed mass-spring type bi-stable vibration energy harvesting system that can be applied to low spaces. A bi-stable vibration system is built using horizontally opposed elastic springs and mass blocks. An elastic composite beam is constructed from an elastic bending plate and spring, and vibration power is generated using a piezoelectric element. An equation of motion is established accounting for the elastic composite beam, and a numerical analysis method based on the Runge-Kutta method is proposed. A formula for predicting the periodic excitation frequency at which stochastic resonance is most likely to occur is derived. A bi-stable vibration energy harvesting experimental device using a piezoelectric element is fabricated, and the proposed numerical analysis method and periodic excitation frequency prediction formula are validated. The amplitude increases and vibration power generation performance due to stochastic resonance are confirmed. In the verification experiment, it was confirmed that the vibration amplitude was expanded more than 7 times and the power generation amount increased by 21%.
Abstract: Improving the efficiency of vibration power generation is an important research topic. Therefore, it is effective to develop a vibration power generation system using a bistable vibration model. The bistable vibration model considered in previous studies has the problem that the center of gravity is high and the vibration power generation efficienc...
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Proposition of a New High Speed and High Efficiency Control Method for Plural Eigen Frequencies by Changing Topology
Toshie Sasaki,
Yang Yang,
Ichiro Hagiwara
Issue:
Volume 10, Issue 6, December 2022
Pages:
135-143
Received:
3 November 2022
Accepted:
17 November 2022
Published:
29 November 2022
DOI:
10.11648/j.ijmea.20221006.12
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Abstract: We have developed many types of transport boxes by origami-operation and space filling operation. But it has not been solved that the fruits, vegetables, strawberries, cells, blood and a bottle of liquor are damaged, broken during transportation. It is the greatest factor in this situation that there is a danger vibration frequency band where these are easy to scratch and are prone to death. If there are eigen frequencies within this danger frequency band, it needs that those eigen frequencies within this danger frequency band are moved out of the band. But it is difficult to apply the existing topology optimization methods using homogenization method or density method to control plural eigen frequencies for two reasons. One reason is that even if homogenization method or density method is used, finally after convergence, holes are made on finite elements of which the size of the homogenizing element or the thickness is smaller than the threshold by keeping the rest the original size. In such processing, there is a possibility that the converged solution again deviates from the convergence value. Another reason is that it is difficult to control plural eigen frequencies simultaneously because some eigen frequencies go up and some ones go down no matter where it is reinforced although displacement at any point goes down in static problem. Although in such way, it is very difficult to control plural eigen frequencies, here we propose a new high precision and high efficiency method for controlling plural eigen frequencies simultaneously using the kinetic energy density and the strain energy density.
Abstract: We have developed many types of transport boxes by origami-operation and space filling operation. But it has not been solved that the fruits, vegetables, strawberries, cells, blood and a bottle of liquor are damaged, broken during transportation. It is the greatest factor in this situation that there is a danger vibration frequency band where these...
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Characteristic Analysis of Two Pairing Origami Polyhedrons and Their Application to Beverage Containers
Aya Abe,
Ichiro Hagiwara,
Yang Yang,
Chie Nara
Issue:
Volume 10, Issue 6, December 2022
Pages:
144-159
Received:
2 November 2022
Accepted:
21 November 2022
Published:
29 November 2022
DOI:
10.11648/j.ijmea.20221006.13
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Abstract: Producing industrial goods with origami structure, such as cans or bottles which can be folded neatly after drinking up, is an idea anyone could easily think of. However, this idea has not been put in practical use yet. Recently, Tachi-Miura polyhedron (TMP) is gaining attention as a 3-dimensional version of Miura-Ori. Meanwhile, Nojima Polyhedron (NP) has been found to be similar as TMP and it is considered that both are able to be analyzed from the point of pairing origami structures proposed by Nojima. The pairing origami is generated by sticking the symmetry 2-dimensional parts to each other to create 3-dimensional shapes. In this study, NP and TMP are focused on and the possibility of the idea is examined. NP which is a mirror symmetry structure and TMP which is a glide symmetry structure, both can be folded not only in the axial but also in the radial direction, and so it would be convenient if they can be applied to beverage containers. In this study, whether both structures are rigid folding or not is investigated geometrically, and then how this gives influence on the energy absorbing characteristics is considered quantically. In the generation of the model, since NP is not rigid folding, a model with accurate coordinates cannot be established because deformation occurs on the surface at the folding stage, so the coordinates are determined by approximation. On the other hand, in the case of TMP, the coordinates of each point can be accurately indicated by parameters, so a model with accurate coordinates is established. Moreover, an engineering possibility to apply both structures in beverage containers is explored by studying their crushing characteristics on simulation. As a result, whether a rigid folding or not has some influence on its deformation mode, however it is shown that it has no influence on the purpose to investigate its possibility for industrialization. This is the first step to make sure the effective usages of the foldable pairing origami structure.
Abstract: Producing industrial goods with origami structure, such as cans or bottles which can be folded neatly after drinking up, is an idea anyone could easily think of. However, this idea has not been put in practical use yet. Recently, Tachi-Miura polyhedron (TMP) is gaining attention as a 3-dimensional version of Miura-Ori. Meanwhile, Nojima Polyhedron ...
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Study of Solar Water Heater Temperature Detection Method
Wenliang Zhu,
Tianyi Huang
Issue:
Volume 10, Issue 6, December 2022
Pages:
160-165
Received:
8 November 2022
Accepted:
23 November 2022
Published:
30 November 2022
DOI:
10.11648/j.ijmea.20221006.14
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Abstract: Based on mass production, cost saving and other commercial ideas, the temperature detection module in solar water heaters usually use inexpensive temperature sensors with low sensitivity and accuracy, the design in the hardware conditions are not ideal conditions, in order to make the temperature detection error to meet the design requirements, the design needs temperature detection range of -10 to 100, the temperature detection error range required to control ± 1, now the Multiple temperature detection methods are compared and studied to come up with a temperature detection method with high stability and low error to meet the design requirements. In this paper, the three methods of fitting, interpolation and table look-up method are compared and analyzed under the condition that the hardware accuracy is not high, and MATLAB software is used to conduct simulation experiments to verify whether the error meets the design requirements, and data are collected in reality to verify whether the accuracy meets the error requirements. The experimental results show that the look-up table method is based on the schematic diagram to get the relationship between the ADC sampling value and the temperature value, with the advantage that environmental errors can be ignored, etc., can better meet the requirements of the accuracy of the solar water heater temperature measurement error, and the performance is more stable and reliable.
Abstract: Based on mass production, cost saving and other commercial ideas, the temperature detection module in solar water heaters usually use inexpensive temperature sensors with low sensitivity and accuracy, the design in the hardware conditions are not ideal conditions, in order to make the temperature detection error to meet the design requirements, the...
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