Resonances of the SD oscillator due to the discontinuous phase

Abstract

Resonance phenomena of a harmonically excited system with mul-tiple potential well play an important role in nonlinear dynamics research.In this paper, we investigate the resonant behaviours of a discontinuous dynamical system with double well potential derived from the SD oscillator to gain better understanding of the transition of resonance mechanism. Firstly,the time dependent Hamiltonian is obtained for a Duffing type discontinuous system modelling snap-through buckling. This system comprises two subsystems connected at x = 0, for which the system is discontinuous. We constructa series of generating functions and canonical transformations to obtain the canonical form of the system to investigate the complex resonant behavioursof the system. Furthermore, we introduce a composed winding number to explore complex resonant phenomena. The formulation for resonant phenomena given in this paper generalizes the formulation of n Omega0 = m Omega used in the regular perturbation theory, where n and m are relative prime integers, Omega 0 and Omega are the natural frequency and external frequencies respectively. Understanding the resonant behaviour of the SD oscillator at the discontinuousphase enables us to further reveal the vibrational energy transfer mechanism between smooth and discontinuous nonlinear dynamical system