Abstract:In recent years, nonlinear energy sink (NES) has been widely used in vibration isolation and anti-impact field with its advantages of wide frequency damping and good robustness. In this paper, a dynamic model of two-stage vibration isolation system with nonlinear energy sink is established for the ship vibration isolation device subjected to impact load. The impact spectrum is used to simulate the shock wave to the base and the transient response of the system is calculated by Runge-Kutta method. The effects of nonlinear stiffness, damping coefficient, and additional mass on the impact resistance of the device are discussed by energy analysis. The calculation results show that the nonlinear energy trap performs well and can significantly reduce the impact energy of the equipment and control the residual vibration in the optimal parameter range.