Static analysis of a passive vibration isolator with quasi-zero-stiffness characteristic

2007 ◽  
Vol 301 (3-5) ◽  
pp. 678-689 ◽  
Author(s):  
A. Carrella ◽  
M.J. Brennan ◽  
T.P. Waters
Keyword(s):  
Static Analysis ◽  
Vibration Isolator ◽  
Stiffness Characteristic

Design and Experimental Analysis of Origami-Inspired Vibration Isolator With Quasi-Zero-Stiffness Characteristic

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Sachiko Ishida ◽  
Kohki Suzuki ◽  
Haruo Shimosaka
Keyword(s):  
Pacific Ocean ◽  
Experimental Analysis ◽  
Frequency Region ◽  
Vibration Isolator ◽  
Spring Stiffness ◽  
Torsional Buckling ◽  
Harmonic Oscillations ◽  
Stiffness Characteristic ◽  
Current Specification ◽  
Isolation Performance

We present a prototype vibration isolator whose design is inspired by origami-based foldable cylinders with torsional buckling patterns. The vibration isolator works as a nonlinear spring that has quasi-zero spring stiffness in a given frequency region, where it does not transmit vibration in theory. We evaluate the performance of the prototype vibration isolator through excitation experiments via the use of harmonic oscillations and seismic-wave simulations of the Tohoku-Pacific Ocean and Kobe earthquakes. The results indicate that the isolator with the current specification is able to suppress the transmission of vibrations with frequencies of over 6 Hz. The functionality and constraints of the isolator are also clarified. It has been known that origami-based foldable cylinders with torsional buckling patterns provide bistable folding motions under given conditions. In a previous study, we proposed a vibration isolator utilizing the bistability characteristics and numerically confirmed the device's validity as a vibration isolator. Here, we attempt prototyping the isolator with the use of versatile metallic components and experimentally evaluate the isolation performance.

The design of negative stiffness spring for precision vibration isolation using axially magnetized permanent magnet rings

2019 ◽  
Vol 25 (19-20) ◽  
pp. 2667-2677 ◽  
Author(s):  
Zhenhua Zhou ◽  
Shuhan Chen ◽  
Dun Xia ◽  
Jianjun He ◽  
Peng Zhang
Keyword(s):  
Vibration Isolation ◽  
Dynamic Stiffness ◽  
Low Frequency ◽  
Design Procedure ◽  
Air Gap ◽  
Negative Stiffness ◽  
Linear Component ◽  
Vibration Isolator ◽  
Stiffness Characteristic ◽  
Isolation Performance

A negative stiffness element is always employed to generate high-static–low-dynamic stiffness characteristic of the vibration isolator, reduce the resonance frequency of the isolator, and improve the vibration isolation performance under low and ultra-low frequency excitation. In this paper, a new compact negative stiffness permanent magnetic spring (NSPMS) that is composed of two axial-magnetized permanent magnetic rings is proposed. An analytical expression of magnetic negative stiffness of the NSPMS is deduced by using the Coulombian model. After analyzing the effect of air-gap width, air-gap position, height difference between the inner ring and outer ring on the negative stiffness characteristic, a design procedure is proposed to realize the negative stiffness characteristic with a global minimum linear component and uniformity stiffness near the equilibrium position. Finally, an experimental prototype is developed to validate the effectiveness of the NSPMS. The experimental results show that combining a vibration isolator with the NSPMS in parallel can lower the natural frequency and improve the isolation performance of the isolator.

Design and Experimental Analysis of Origami-Inspired Vibration Isolators With Quasi-Zero-Stiffness Characteristic

2016 ◽  
Author(s):  
Sachiko Ishida ◽  
Kohki Suzuki ◽  
Haruo Shimosaka
Keyword(s):  
Experimental Analysis ◽  
Frequency Region ◽  
Vibration Isolator ◽  
Spring Stiffness ◽  
Torsional Buckling ◽  
Harmonic Oscillations ◽  
Vibration Isolators ◽  
Stiffness Characteristic ◽  
Current Specification ◽  
Isolation Performance

We present a prototype vibration isolator whose design is inspired by origami-based foldable cylinders with torsional buckling patterns. The vibration isolator works as a nonlinear spring that has quasi-zero spring stiffness in a given frequency region, where it does not transmit vibration in theory. We evaluate the performance of the prototype vibration isolator through excitation experiments via the use of harmonic oscillations and seismic-wave simulations of the Tohoku-Pacific Ocean and Kobe earthquakes. The results indicate that the isolator with the current specification is able to suppress the transmission of vibrations with frequencies of over 6 Hz. The functionality and constraints of the isolator are also clarified. It has been known that origami-based foldable cylinders with torsional buckling patterns provide bistable folding motions under given conditions. In a previous study, we proposed a vibration isolator utilizing the bistability characteristics and numerically confirmed the device’s validity as a vibration isolator. Here, we attempt prototyping the isolator with the use of versatile metallic components and experimentally evaluate the isolation performance.

A study of a nonlinear vibration isolator with a quasi-zero stiffness characteristic

2008 ◽  
Vol 315 (3) ◽  
pp. 700-711 ◽  
Author(s):  
Ivana Kovacic ◽  
Michael J. Brennan ◽  
Timothy P. Waters
Keyword(s):  
Nonlinear Vibration ◽  
Vibration Isolator ◽  
Stiffness Characteristic

Design and experimental validation of a vibration isolator with high-static low-dynamic stiffness and operating point variable property

2021 ◽  
pp. 107754632199052
Author(s):  
Zhenhua Zhou ◽  
Minrui Zhou ◽  
Zhihui Dai ◽  
Xin Liu ◽  
Zhanhui Li
Keyword(s):  
Experimental Validation ◽  
Dynamic Stiffness ◽  
Negative Stiffness ◽  
Vibration Isolator ◽  
Coil Spring ◽  
Variable Property ◽  
Leaf Springs ◽  
Stiffness Characteristic ◽  
Vibration Transmissibility ◽  
And Performance

Vibration isolator with high-static low-dynamic stiffness property has been researched extensively, but the isolator’s stability and performance will be deteriorated with the operation point variation. In this article, a vibration isolator that operation point can be variable was proposed, and it was constructed by combining a coil spring and flexible leaf springs with a negative stiffness magnet spring in parallel. Unlike previous studies, this article focuses on the realization of the high-static low-dynamic stiffness characteristic of the isolator, and the operation point of the vibration isolator can be varied in a certain range. The effects of configuration parameters on the negative stiffness are investigated in detail. Furthermore, the designing procedure to realize the linear negative stiffness with the expected magnitude and range was also developed. A prototype was installed and the vibration transmissibility of the system at different operation points was measured, the experimental results indicated that the isolator can be kept stable in different operation points, and the performance does not deteriorate with the variation of the operation point. The effectiveness of the designing procedure of the realization of linear negative stiffness with the expected magnitude and range and the variable of the operation point of the isolator was validated.

Sign in / Sign up

Export Citation Format

Share Document