Abstract
Modal differential sub-structure method which can quickly predict effects of structural modifications has been proposed by the authors. This method is a kind of component modal synthesis and utilizes dynamic current characteristics of modification structure. The method is convenient because it does not require the user to determine the structure modification segmentation beforehand and the user can choose it after checking dynamic characteristics of current structure. This paper elucidates the difference of formulation between the proposed method and conventional methods. As with other component modal synthesis methods, however, the predictions of effects of structural modifications with this method involve errors. In this paper, a technique to reduce those errors is proposed and the method is compared with conventional methods in terms of error reduction effect and computational efficiency.
