Stochastic resonance in a nonlinear mechanical vibration isolation system

•A nonlinear mechanical isolation system for stochastic resonance is modeled.•Component of force transmitted though isolator is masked by adding very low noise.•Stochastic anti-resonance of transmitted force occurs before stochastic resonance.•Noise intensity for stochastic resonance is increased as frequency increasing.•Stochastic resonance in mechanical system is validated by experiment work.

This paper concerns the effect that a stochastic resonance can have on a vibration isolation system. Rather than reducing the transmitted force, it is shown that it is possible to significantly mask the component of the force transmitted though the isolator, when the system is excited harmonically. This can be achieved by adding a very low intensity of random noise to the harmonic excitation force. The nonlinear mechanical vibration isolation system used in the study consists of a vertical linear spring in parallel with two horizontal springs, which are configured so that the potential energy of the system has a double-well. Prior to the analytical and numerical study, an experiment to demonstrate stochastic resonance in a mechanical system is described.