Modeling, analysis, and simulation of X-shape quasi-zero-stiffness-roller vibration isolators

Abstract

Existing quasi-zero stiffness (QZS) isolators are reviewed. In terms of their advantages, a novel X-shape QZS isolator combined with the cam-roller-spring mechanism (CRSM) is proposed. Different from the existing X-shape isolators, oblique springs are used to enhance the negative stiffness of the system. Meanwhile, the CRSM is used to eliminate the gravity of the loading mass, while the X-shape structure leaves its static position. The existing QZS isolators are demonstrated and classified according to their nonlinearity mechanisms and classical shapes. It is shown that the oblique spring can realize negative stiffness based on the simplest mechanism. The X-shape has a strong capacity of loading mass, while the CRSM can achieve a designed restoring force at any position. The proposed isolator combines all these advantages together. Based on the harmonic balance method (HBM) and the simulation, the displacement transmissibilities of the proposed isolator, the X-shape isolators just with oblique springs, and the X-shape isolators in the traditional form are studied. The results show that the proposed isolator has the lowest beginning isolation frequency and the smallest maximum displacement transmissibility. However, it still has some disadvantages similar to the existing QZS isolators. This means that its parameters should be designed carefully so as to avoid becoming a bistable system, in which there are two potential wells in the potential energy curve and thus the isolation performance will be worsened.

Research on a Novel CRSM for a Type of QZS Vibration Isolator

“…Since CRSM is capable of yielding a specified restoring force irrespective of the displacement and the X-shape structure has strong load support ability, a novel QZS vibration isolator combining an X-shape configuration and CRSM structure is proposed [11]. A new parabolic cam-roller is designed and used in QZS isolator, and some important theoretical equations are given and the conditions for QZS characteristics are obtained [12].…”

Vibration isolation performance analysis of a bilateral supported bio-inspired anti-vibration control system

“…Yan et al [21] developed a nonlinear compensation method for realizing various QZS, and verified it with a rhombus structure. Mao et al [22] designed a novel X-shape QZS isolator combined with the cam-roller-spring mechanism, which had the lowest beginning isolation frequency and the smallest maximum displacement transmissibility.…”