微小分系のマスラインの変更による全系の周波数応答関数の整形

抄録

This paper addresses to clarify the contribution of a mass property of a small subsystem to the frequency responses of a whole structure. Based on both a Frequency Response Function (FRF) based sub-structuring and a kernel compliance analysis, it is expected that the control of a mass line of a subsystem’s FRF may dominates the shape the FRF of a whole structure. Our proposed analysis method decomposes, at first, a whole structure of interest into two different sizes of subsystems. In this decomposition, a small part only is subjected to structural changes. Since the FRFs on interface DOFs of these two subsystems dominate the frequency responses of a whole structure and determine the forces transmitted through the interface DOFs, the FRFs on interface DOFs of the small part (subsystem) have also a critical role for determining the frequency responses. However, in the frequency range of lower modes of a whole structure, the FRFs of the small part is simply dominated by rigid body modes and have no resonance. The FRFs in this frequency range are, therefore, dominated by a mass property of a small subsystem. Finally, this paper shows that it is possible to shape the frequency response function of the whole system by changing the small subsystem through a concrete numerical example.