著者

富田 直 西垣 英一 表 竜二

出版者

一般社団法人 日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2019, 2019

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<p>Lightweight structure is required due to ecological considerations. However, the lightweight requirements conflict with noise and vibration (NV) performance. To satisfy both of lightweight solution and NV performance, vibration reduction based on periodic structures is of interest because the periodic structures have wave filtering characteristics which inhibit elastic wave propagation at the frequency ranges referred as band gaps.</p><p>This paper presents a vibration reduction method using the band gaps of periodic shell structures. The frequency of band gaps can be calculated by using reduced FEA model which is applied the Bloch's theory. We can design shapes of unit cells using the calculated band gaps which relate to frequency range with vibration reduction. Frequency response of a finite periodic shell is carried out to demonstrate vibration reduction based on the band gaps. The results of analysis suggested that the band gaps of periodic shell restrain formation of natural vibration.</p>

著者

朝賀 泰男 西垣 英一 青井 一郎 杉浦 豪軌 槇野 浩司

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00088-17-00088, 2017 (Released:2017-09-25)

参考文献数

13

被引用文献数

1

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As manufacturing has begun to move from mass production to mass customization, manufacturing industries are currently constructing the architecture to provide wide variety of products in countries around the world. Modular design and standardization is effective for mass customization. In recent years, modular design techniques have been researched in vehicle development. Then, car manufacturers have been announcing their own architecture about the car design. We have focused on pipe-based components as the standardized member of body structure. Since the pipe is a general-purpose member, we can get them easily. In this study, we have developed new design techniques for body structure consist of the pipe-based standardized components. Firstly, we have designed base frame layout by topology optimization formulated Min-Max approach for multiple load cases. Secondly, we have calculated cross-sectional design parameters by discrete design value table and fully stressed design. Using these techniques based on modular design rules, we can obtain body structure consisting of standardized components which are subjected to stress lower than the yield strength. As a case study, we have applied our unique modular design techniques to the rear body structure model.

著者

西垣 英一 朝賀 泰男

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00065-17-00065, 2017 (Released:2017-09-25)

参考文献数

13

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This paper describes a modularization method based on the creation of a new layout structure by combining topology optimization using beam elements and clustering analysis. By setting candidates for frame members in smaller units than parts and performing topology optimization using beam elements, a frame structure of new layouts as an aggregate of fine frame members can be created. For each fine frame member, connectivity as a structure in the entire frame structure is expressed as Design Structure Matrix (DSM). By performing hierarchical clustering on this DSM, clusters of fine frame members are formed as parts, and modules as these aggregate can be found out. Since this is hierarchically determined as a dendrogram, it is possible to determine the number of module divisions of the product configuration depending on the granularity of the cluster. Furthermore, by advancing each fine cluster towards the trunk above the tree diagram, an assembly process with less rework is obtained. Unlike the method of deriving the optimal solution for the product with existing structure, this research proposes a method to derive concurrently the new frame structure and construction of parts and module decomposition which minimizes rework. By validation analysis using a simple box structure, the effectiveness of this proposed method has been confirmed.

著者

鶴見 康昭 中川 稔章 西垣 英一 西脇 眞二 小島 芳生 菊地 昇

出版者

一般社団法人日本機械学会

雑誌

設計工学・システム部門講演会講演論文集 (ISSN:13480286)

巻号頁・発行日

vol.2001, no.11, pp.279-281, 2001-11-01

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An integrated system with both Computer Aided Design (CAD) and Computer Aided Engineering (CAE) has been developed. Most of these systems mainly focus on the effectiveness of constructing Finite Element (FE) model In these systems, a FE model is automatically constructed and calculation is automatically carried out. But a good design candidate cannot be obtained since some analysis tools for finding out it effectively are not included. In this paper, firstly some problems in current CAE systems are made clear. Secondly, in order to overcome these problems, two new analyses, that are FOA( First Order Analysis) in a concept design phase and a optimization tool based on a reduction technique in detailed design phase, are presented. Finally, in order to perform these analyses in a integrated system, a few concepts of necessary technique are proposed.