A nonlinear quasi-zero-stiffness vibration isolation system with additional X-shaped structure: Theory and experiment

• Published in: Mechanical systems and signal processing Vol. 177; p. 109208
• Main Authors: Xiong, Yuanhao, Li, Fengming, Wang, Yu
• Format: Journal Article
• Language: English
• Published: Berlin Elsevier Ltd 01.09.2022; Elsevier BV
• Subjects: Amplitude-frequency response; Bearing strength; Harmonic balance method; Isolation systems; Load carrying capacity; Mathematical models; Quasi-zero-stiffness vibration isolator with additional X-shaped structure; Stiffness; Vibration analysis; Vibration experiments; Wide quasi-zero-stiffness interval; Amplitude-frequency response; Harmonic balance method; Vibration experiments; Quasi-zero-stiffness vibration isolator with additional X-shaped structure; Wide quasi-zero-stiffness interval
• ISSN: 0888-3270; 1096-1216
• DOI: 10.1016/j.ymssp.2022.109208

•A nonlinear quasi-zero-stiffness vibration isolation system is proposed and designed.•The vibration isolation system has ultra-low starting frequency for vibration isolation.•The vibration isolation system has wide quasi-zero-stiffness range.•Experiments are conducted to validate the theoretical and numerical results. A novel nonlinear quasi-zero-stiffness (QZS) vibration isolation system with high load carrying capacity is proposed. By connecting X-shaped structure with a platform, the quasi-zero-stiffness vibration isolation system with additional X-shaped structure (X-QZS) is designed. The relationships of system restoring force and stiffness related to displacement are obtained by static modelling, and the influences of the parameters on the system stiffness are analyzed. In the dynamic analysis, the amplitude-frequency characteristics and transmissibility curves are calculated by the harmonic balance method. The correctness of the calculation results is verified by numerical simulation and vibration experiments. From the investigations, it is observed that the designed X-QZS system has a wide QZS interval, a small unstable interval, a low jump-down frequency, and a high load carrying capacity. These results can provide a useful reference for improving the performance of QZS vibration isolation systems.