APPROXIMATE METHODS FOR CALCULATION OF NONLINEAR INSTANTANEOUS MODE SHAPES

摘要

Mode-like behavior is frequently observed in nonlinear system vibration. It is an important task to understand and evaluate nonlinear modal properties. In this paper, basic concepts of nonlinear modes are briefly reviewed and an approximate method for calculation of instantaneous mode shapes is presented. The method is applied to a 3DOF nonlinear system and the result is compared with numerically simulated mode shape.