Inner resonance of a coupled hyperbolic tangent nonlinear oscillator arising in a packaging system

In this paper, a dynamic model of a coupled hyperbolic tangent nonlinear oscillator arising in a packaging system is proposed. Conditions for resonance are obtained by applying the variational iteration method-II (VIM-II), which should be avoided in the cushioning packaging design. Moreover, the comparison between the VIM-II and numerical solutions indicates an excellent agreement.