著者
篠崎 貴宏 本家 浩一
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.855, pp.17-00176-17-00176, 2017 (Released:2017-11-25)
参考文献数
13
被引用文献数
1

This paper proposes identification method of excitation force of rigid body vibration source by physical model identification. If the reworking occurs after the assembly of the prototype in mechanical product, the cost increases due to the retrofit countermeasures and development period extension. Pre-prediction of vibration at the design stage is important to avoid these problems. Prior prediction of vibration needs to grasp the excitation force of the vibration source. As conventional methods, the mount stiffness method and the matrix inversion method have been proposed. However, mount stiffness method calculates the mount transmission force. Therefore, if the development machine changes the structure, preliminary evaluation does not apply. The matrix inversion method can solve this problem. However, when the frequency response function contains a measurement error, the error spreading propagates in inverse matrix calculation. Therefore, in order to avoid the inverse matrix calculation, we propose identification method of excitation force of rigid body vibration source by physical model identification. In this paper, it was investigated features of the inverse matrix method and the identification method of excitation force by physical model identification using the basic experiment. As a result of study, the method by physical model identification showed that the influence of measurement error is smaller than the matrix inversion method. In addition, it showed that it is possible to identify the excitation force with fewer excitation points than the matrix inversion method.
著者
本家 浩一 増田 京子 次橋 一樹 杉本 明男
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.855, pp.17-00173-17-00173, 2017 (Released:2017-11-25)
参考文献数
9

The Impact damper with granular materials has a high damping effect for wide frequency range and it is used in many fields. Many researches have been made on the prediction of the damping effect of this damper on one degree of freedom spring-mass system. But it is more useful to be able to predict the damping effect when applied to a real complex structure. For this purpose, numerical modeling of damping effect of an impact damper is important for efficient design of structures set with dampers. In this paper, the granular materials are modeled as one mass point of restitution coefficient of zero that undergo displacement vibration excitation, and the motion of this mass point is theoretically analyzed for the case of vertical vibration and one side collision. From these results, we propose a method for obtaining the macroscopic damping effect of the impact damper with granular materials. This is obtained as a nonlinear equivalent mass ratio and nonlinear damping coefficient with amplitude dependence. Further the excitation experiment which identified the damping characteristic of the damper was carried out. Theoretical solution and experimental result show the good coincidence.