Spectral Analysis Method for Nonlinear Dynamic Systems

Abstract

This paper introduces a FFT-based spectral analysis method (SAM) for the nonlinear dynamic systems whose dynamic behaviors can be represented by the ordinary nonlinear differential equations. To verify the proposed SDM, a damped Duffing's equation is considered as an example nonlinear problem, and the phase diagrams obtained by the present SAM are compared with those obtained by other solution methods such as the method of multiple scales and the Runge-Kutta method.