Analysis and Experiment of Vibration Isolation Performance of a Magnetic Levitation Vibration Isolator with Rectangular Permanent Magnets

Abstract A novel passive asymmetric quasi-zero stiffness vibration isolator (AQZS-VI) comprising two linear springs acting in parallel with one negative stiffness element (NSE) is proposed, of which the NSE is mainly constructed by the combination of cantilever plate spring and L-shaped lever (CPS-LSL). The static model of the isolator is deduced considering the geometrical nonlinearity of the NSE and the bending deformation of plate spring. The nonlinear stiffness properties of the CPS-LSL and the AQZS-VI, as well as the nonlinear damping properties of the AQZS-VI are discussed. The absolute displacement transmissibility of the AQZS-VI under base displacement excitation is obtained using Harmonic Balance Method, and the effects of different excitation amplitudes and damping factors on the vibration isolation performance are analyzed. Better than other quasi-zero stiffness vibration isolators (QZS-VI) whose NSEs do not provide supporting force at zero stiffness point, the NSE of the AQZS-VI provides more supporting force than the parallel connected linear springs, which is very beneficial for improving the bearing capacity of the isolator. Compared with a typical symmetric QZS-VI with same damping property, the AQZS-VI has longer stroke with low stiffness and lower peak value of displacement transmissibility. The prototype experiments indicate that the AQZS-VI outperforms the linear counterpart with much smaller starting frequency of vibration isolation and lower displacement transmissibility. The proposed AQZS-VI has great potential for applying in various engineering practices with superior vibration isolation performance.

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Research on Influence of Vibration Isolator Arrangement on Vibration Isolation Performance

Open Journal of Acoustics and Vibration ◽

10.12677/ojav.2019.73013 ◽

2019 ◽

Vol 07 (03) ◽

pp. 120-127

Author(s):

伟黄

Keyword(s):

Vibration Isolation ◽

Vibration Isolator ◽

Vibration Isolation Performance ◽

Isolation Performance

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A study of the vibration isolation performance of a limited phononic crystal vibration isolator based on local resonance theory

Journal of Applied Physics ◽

10.1063/5.0013617 ◽

2020 ◽

Vol 128 (13) ◽

pp. 134903

Author(s):

Caiyou Zhao ◽

Xin Gao ◽

Liuchong Wang ◽

Qiang Yi ◽

Ping Wang

Keyword(s):

Vibration Isolation ◽

Phononic Crystal ◽

Vibration Isolator ◽

Resonance Theory ◽

Local Resonance ◽

Vibration Isolation Performance ◽

Isolation Performance

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Experimental study on on-orbit and launch environment vibration isolation performance of a vibration isolator using bellows and viscous fluid

Aerospace Science and Technology ◽

10.1016/j.ast.2015.04.012 ◽

2015 ◽

Vol 45 ◽

pp. 1-9 ◽

Cited By ~ 26

Author(s):

Dae-Oen Lee ◽

Geeyong Park ◽

Jae-Hung Han

Keyword(s):

Experimental Study ◽

Viscous Fluid ◽

Vibration Isolation ◽

Vibration Isolator ◽

Vibration Isolation Performance ◽

Isolation Performance

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On-orbit Micro-vibration Isolation Performance Verification for Spaceborne Cryocooler Passive Vibration Isolator Using SMA Mesh Washer

Transactions of the Korean Society for Noise and Vibration Engineering ◽

10.5050/ksnve.2015.25.1.024 ◽

2015 ◽

Vol 25 (1) ◽

pp. 24-32

Author(s):

Seong-Cheol Kwon ◽

Su-Hyeon Jeon ◽

Hyun-Ung Oh

Keyword(s):

Vibration Isolation ◽

Vibration Isolator ◽

Performance Verification ◽

Micro Vibration ◽

Vibration Isolation Performance ◽

Isolation Performance

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Design and Research of Semiactive Quasi-Zero Stiffness Vibration Isolation System for Vehicles

Shock and Vibration ◽

10.1155/2021/5529509 ◽

2021 ◽

Vol 2021 ◽

pp. 1-22

Author(s):

Shaohua Li ◽

Guizhen Feng ◽

Quan Zhao

Keyword(s):

Embedded System ◽

Vibration Isolation ◽

Test System ◽

Isolation Effect ◽

Vertical Acceleration ◽

Vibration Isolator ◽

Isolation System ◽

Labview Software ◽

Vibration Isolation Performance ◽

Isolation Performance

The vehicle-mounted equipment is easy to be disturbed by external vibration excitations during transportation, which is harmful to the measurement accuracy and performance of the equipment. Aiming at the vibration isolation of the vehicle-mounted equipment, a semiactively controlled quasi-zero stiffness (QZS) vibration isolator with positive and negative stiffness is proposed. The vertical spring is paralleled with a magnetorheological (MR) damper, and the semiactive on-off control scheme is adopted to control the vibration. The analytical expression of the isolator’s displacement transmissibility is derived via the averaging method. Then, the vibration isolation performance under different road excitations and different driving speeds is simulated and compared with the uncontrolled passive QZS vibration isolator. In addition, the mechanical structure of the semiactive QZS isolator is designed and manufactured, and the test system is built by LabVIEW software and PXI embedded system. The isolation effect of the semiactive QZS isolator is verified through test data. It is found that the proposed semiactive QZS isolator shows excellent vibration isolation performance under various road excitations, while the passive QZS isolator is effective only under harmonic excitations. The vertical acceleration of vehicle-mounted device can be decreased over 70% after isolation, and the vibration isolation effect is remarkable. The design idea and research results of the semiactive QZS isolator may provide theoretical guidance and engineering reference for vibration isolation.

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A Vibration Isolation System Using the Negative Stiffness Corrector Formed by Cam-Roller Mechanisms with Quadratic Polynomial Trajectory

Applied Sciences ◽

10.3390/app10103573 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3573 ◽

Cited By ~ 1

Author(s):

Mengnan Sun ◽

Zhixu Dong ◽

Guiqiu Song ◽

Xingwei Sun ◽

Weijun Liu

Keyword(s):

Vibration Isolation ◽

Quadratic Polynomial ◽

Negative Stiffness ◽

Calculation Error ◽

Vibration Isolator ◽

Isolation System ◽

Frequency Wave ◽

Vibration Isolation System ◽

Vibration Isolation Performance ◽

Isolation Performance

The vibration isolator equipped with a negative stiffness corrector (NSC) excels at vibration isolation, but its stiffness often presents complex nonlinearity which needs to be approximated in calculation. To avoid the harmful effects of approximate stiffness, the NSC formed by the cam-roller mechanism with a quadratic polynomial trajectory (QCRM) is proposed to construct the vibration isolation system. From the inherent geometrical relationship in the structure, the generation mechanism of high-static-low-dynamic stiffness is analyzed, and the quasi-zero stiffness (QZS) condition of the system is derived. Based on the dynamic model of the QZS vibration isolator, the functions of response characteristics are solved by the harmonic balance method. Then, the absolute displacement transmissibility with different parameter values, and the vibration isolation performance under sinusoidal, multi-frequency wave, and random excitations are discussed. The simulated results show that the stiffness expression of the proposed QZS vibration isolator is directly a quadratic function, which removes the calculation error caused by approximate stiffness at large displacement and broadens the available isolation displacement range. Introducing the QCRM-NSC can significantly suppress the low-frequency vibration and resonance response without changing the load-bearing capacity of the vibration isolator. Under various excitations, the vibration isolation performance of the QZS vibration isolator all outperforms the linear counterpart.

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Vibration control of an unbalanced system using a quasi-zero stiffness vibration isolator with fluidic actuators and composite material: An experimental study

Journal of Vibration and Control ◽

10.1177/10775463211051458 ◽

2022 ◽

pp. 107754632110514

Author(s):

Sivakumar Solaiachari ◽

Jayakumar Lakshmipathy

Keyword(s):

Composite Material ◽

Nonlinear Vibration ◽

Vibration Isolation ◽

Basalt Fiber ◽

Experimental Investigations ◽

Vibration Isolator ◽

Coil Spring ◽

Linear Type ◽

Fluidic Actuators ◽

Isolation Performance

In this study, a new type of vibration isolator based on fluidic actuators and a composite slab was tested experimentally with an unbalanced disturbance. Quasi-zero stiffness vibration isolation techniques are advanced and provide effective isolation performance for non-nominal loads. The isolation performance of the proposed isolator was compared to that of a nonlinear vibration isolator equipped with fluidic actuators and a mechanical coil spring (NLVIFA). The NLVIFA system is better suited to non-nominal loads; however, the mechanical spring axial deflection leads to limited amplitude reduction in the system. To address this issue, a cross buckled slab was developed to replace a mechanical coil spring for absorbing vertical deflection by transverse bending, which is made of a specially developed composite material of Basalt fiber reinforced with epoxy resin and enhanced with graphene nano pellets. This current study was concerned with the theoretical analysis and experimental investigations of the proposed nonlinear vibration isolator with fluidic actuators and composite material (NLVIFA-CM), which performs under quasi-zero stiffness characteristics. Because of its reduced axial deflection, the theoretical and experimental results show that the NLVIFA-CM system outperforms the NLVIFA system and other linear type vibration isolators in terms of isolation performance. Furthermore, the proposed vibration isolator makes a significant contribution to low-frequency vibration.

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