Parameter design of a multi-delayed isolator with asymmetrical nonlinearity

In this study, based on the analysis of multiple nonlinear vibration properties, the criterions of parameter design for different types of excitations and structural nonlinearities are proposed for vibration isolation. For a nonlinear vibration isolation system with Quasi-Zero-Stiffness property, the assembly process and stiffness property with different masses of isolation object are taken into account. In order to improve the isolation effectiveness in a wide frequency band, the relation between vibration performances and parameters is established. The effect of adjustable parameters on the vibration features and the effect mechanisms of multiple time delays are discussed in details based on the method of multiple scales. Because the study takes full consideration of the effect of structural nonlinearity and transition mechanism of vibration performances, the proposed criterions for parameter design could solve the conflict between the improvement of isolation effectiveness and complexity or bifurcation brought by nonlinearity. The results in this paper show that without changing the High-Static-Low-Frequency advantage brought by the nonlinear isolation structure, the isolation effectiveness could be improved in a wide frequency band. (C) 2018 Elsevier Ltd. All rights reserved.