A Novel Nonlinear Approach to Suppress Resonant Vibrations

A novel approach to suppress resonant vibration is presented by employing a single degree of freedom transmissibility system which utilises a nonlinear damping element. Studies ahve shown that the nonlinear damping element can reduce the output energy at the driving frequency and at the same time spread the output signal energy over a wider range of harmonics. It will also be shown that that the reduction becomes larger as the nonlinear damping characteristic gets stronger, and in most cases the power at the harmonics in the output spectrum will be much less if the nonlinear damping characteristic is an odd function. Hence, an odd polynomial nonlinear damping element can be introduced between the incoming signal and the structure of interest to suppress resonant vibration. An expression is derived to express the transmitted force spectrum in terms of the nonlinear generalised frequency response functions, to clearly show how the energy, at the excitation frequency, is modified by the nonlinearity.