Dynamic performance of an HSLDS-SMI isolator with primary mass variation

The high-static-low-dynamic-stiffness (HSLDS) isolator is sensitive to mass deviation, which causes a shift in static equilibrium and results in softening of the dynamic response. This study introduces sliding mass inertia (SMI) to an HSLDS to mitigate the softening and enhance the dynamic performance of the system under mass deviation. The harmonic balance method (HBM) is employed to obtain the dynamic response of the vibrating system with the proposed nonlinear isolator. Key characteristics, such as the backbone curve, amplitude-frequency response, resonance peak, and displacement transmissibility are analyzed in detail through parametric analysis. The results indicate that mass deviation worsens the softening behavior of the HSLDS isolator. A higher mass deviation ratio results in an increase in both the amplitude and the resonance frequency of the system. Fortunately, however, the sliding mass eliminates the softening behavior, reduces the peak response, and improves the overall dynamic performance.