Journal Article

An innovative design of parabolic cam-roller quasi-zero-stiffness isolators for ultralow frequency vibration isolation

Zhang, Yongshan, Luo, Quantian, Zuo, Song, Wang, Dayang

2024

Overview

Quasi-zero-stiffness (QZS) isolator with high-static-low-dynamic stiffness can withstand heavy loads and effectively isolate vibration with low frequency. However, the ultralow frequency vibration isolation is still a challenge for the existing QZS isolators. This paper proposes an innovative design of parabolic cam-roller QZS isolators by use of nonlinear subsidiary systems to achieve ultralow dynamic stiffness and ultralow frequency vibration isolation. The theoretical formulations of the proposed QZS isolators are derived. The effects of structural parameters on stiffness characteristics are analyzed and then an optimal design are presented. The vibration isolation of the proposed QZS isolators under harmonic excitation is investigated using the averaging method, and dynamic response under impact load is studied using the Runge–Kutta algorithm. The bifurcation analysis for the designed QZS isolator is briefly presented. In comparison with the previous parabolic cam-roller QZS isolator with the linear subsidiary system and the existing QZS isolators with the nonlinear subsidiary systems, the present QZS isolators have lower stiffness in a wider displacement region, which makes them be able to isolate harmonic excitations with larger amplitude and have better isolation performance for harmonic excitations and impact loading. A prototype of the proposed QZS isolator is designed, fabricated and tested. Experimental results show that the measured force–displacement curves are in good agreement with those predicted by theory, and isolation performance of the proposed QZS isolators for vibration with ultralow frequency significantly outperforms the existing QZS isolator. Graphical abstract

• Publisher: Springer Netherlands,Springer Nature B.V
• Subject: Algorithms / Automotive Engineering / Bifurcations / Classical Mechanics / Control / Design / Design analysis / Dynamic response / Dynamical Systems / Engineering / Extremely low frequencies / Harmonic excitation / Impact analysis / Impact loads / Isolators / Mechanical Engineering / Nonlinear systems / Runge-Kutta method / Stiffness / Systems analysis / Vibration / Vibration analysis / Vibration measurement