Geometrically nonlinear inerter for vibration suppression

A two-degree-of-freedom (2DOF) vibration isolation structure with an integrated geometric nonlinear inerter (NI) device is proposed. The device is integrated into an inertial nonlinear energy sink (INES), and its vibration suppression performance is examined by the Runge-Kutta (RK) method and verified by the harmonic balance method (HBM). The new isolator is compared with a traditional vibration isolator. The results show a significant improvement in the vibration suppression performance. To investigate the effects of the excitation amplitude and initial condition on the dynamics of the system, a series of transmissibility-frequency response analyses are performed based on the displacement transmissibility. The energy flow of the system is analyzed, and numerous calculations reveal a series of ideal values for the energy sink in the NI-INES system. This study provides new insights for the design of vibration isolators.