Performance testing for an active/passive vibration isolation and steering system

1996 ◽  
Author(s):  
Jeanne Sullivan ◽  
James Gooding ◽  
Michelle Idle ◽  
Alok Das ◽  
Terance Hoffman ◽  
...  
Keyword(s):  
Vibration Isolation ◽  
Performance Testing ◽  
Steering System ◽  
Passive Vibration Isolation

scholarly journals Tilt Active Vibration Isolation Using Vertical Pendulum and Piezoelectric Transducer with Parallel Controller

2021 ◽  
Vol 11 (10) ◽  
pp. 4526
Author(s):  
Lihua Wu ◽  
Yu Huang ◽  
Dequan Li
Keyword(s):  
Piezoelectric Transducer ◽  
Vibration Isolation ◽  
Vertical Vibration ◽  
Open Loop ◽  
Negative Effects ◽  
Voltage Controller ◽  
Hysteresis Nonlinearity ◽  
Passive Vibration Isolation ◽  
Active Vibration ◽  
Active Vibration Isolation

Tilt vibrations inevitably have negative effects on some precise engineering even after applying horizontal and vertical vibration isolations. It is difficult to adopt a traditional passive vibration isolation (PVI) scheme to realize tilt vibration isolation. In this paper, we present and develop a tilt active vibration isolation (AVI) device using a vertical pendulum (VP) tiltmeter and a piezoelectric transducer (PZT). The potential resolution of the VP is dependent on the mechanical thermal noise in the frequency bandwidth of about 0.0265 nrad, which need not be considered because it is far below the ground tilt of the laboratory. The tilt sensitivity of the device in an open-loop mode, investigated experimentally using a voltage controller, is found to be (1.63±0.11)×105 V/rad. To compensate for the hysteresis nonlinearity of the PZT, we experimentally established the multi-loop mathematical model of hysteresis, and designed a parallel controller consisting of both a hysteresis inverse model predictor and a digital proportional–integral–differential (PID) adjuster. Finally, the response of the device working in close-loop mode to the tilt vibration was tested experimentally, and the tilt AVI device showed a good vibration isolation performance, which can remarkably reduce the tilt vibration, for example, from 6.0131 μrad to below 0.0103 μrad.

scholarly journals Effects and Prospects of the Vibration Isolation Methods for an Atomic Interference Gravimeter

Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 583
Author(s):  
Wenbin Gong ◽  
An Li ◽  
Chunfu Huang ◽  
Hao Che ◽  
Chengxu Feng ◽  
...  
Keyword(s):  
Vibration Isolation ◽  
Prospective Development ◽  
Passive Vibration Isolation ◽  
Isolation Methods ◽  
Challenging Environment ◽  
Research Findings ◽  
Active Vibration ◽  
Vibration Compensation ◽  
Atomic Interference ◽  
Vibration Noise

An atomic interference gravimeter (AIG) is of great value in underwater aided navigation, but one of the constraints on its accuracy is vibration noise. For this reason, technology must be developed for its vibration isolation. Up to now, three methods have mainly been employed to suppress the vibration noise of an AIG, including passive vibration isolation, active vibration isolation and vibration compensation. This paper presents a study on how vibration noise affects the measurement of an AIG, a review of the research findings regarding the reduction of its vibration, and the prospective development of vibration isolation technology for an AIG. Along with the development of small and movable AIGs, vibration isolation technology will be better adapted to the challenging environment and be strongly resistant to disturbance in the future.

Modal Analysis of Magnetic Resonance Imaging (MRI) Scanner Support Structure

2018 ◽  
Author(s):  
Geneviève Rodrigue ◽  
Chris K. Mechefske
Keyword(s):  
Modal Analysis ◽  
Vibration Isolation ◽  
Natural Frequencies ◽  
Design Tool ◽  
Mode Shapes ◽  
Resonance Imaging ◽  
Support Structure ◽  
Analysis And Design ◽  
Passive Vibration Isolation ◽  
Magnetic Resonance Imaging Mri

Experimental and computational modal analysis has been completed as part of a larger project with the ultimate goal of understanding MRI vibration and implementing passive vibration isolation in the MRI machine support structure. The specific purpose of the modal analysis is to extract natural frequencies (eigenvalues) and mode shapes (eigenvectors) of the MRI support structure in order to validate the computational model of the base against the experimental results so that the former may be used as an analysis and design tool. From the model, the resonance points of the MRI support structure are determined within the expected frequency ranges of excitation.

scholarly journals Implementation of the KDamper concept using disc springs

2018 ◽  
Vol 38 (1) ◽  
pp. 168-186
Author(s):  
Ioannis E Sapountzakis ◽  
Pavlos G Tranakidis ◽  
Ioannis A Antoniadis
Keyword(s):  
Structural Design ◽  
Vibration Isolation ◽  
Short Review ◽  
Optimal Combination ◽  
Negative Stiffness ◽  
External Excitation ◽  
Main Concept ◽  
Initial Displacement ◽  
Passive Vibration Isolation ◽  
Selection Of

The KDamper is a novel passive vibration isolation and damping concept, based essentially on the optimal combination of appropriate stiffness elements, which include a negative stiffness element. In this paper, after a short review of the optimal design and the selection of the parameters of the KDamper, the main concept focuses on the implementation of the negative stiffness elements with a set of Belleville (disc) springs. The major benefits of the proposed structure are the size and the robustness of the structure. The theory and the design process of the disc springs are presented thoroughly, as well as of the spiral springs with ground ends, along with an initial structural design. Simulation results from three different case scenarios are demonstrated; for an initial displacement, an initial velocity and an external excitation. The results obtained from the simulations show very satisfactory behavior.

Passive vibration isolation of flexure jointed hexapod: A geometry design method

2020 ◽  
pp. 095440622095448
Author(s):  
Zongyu Zuo ◽  
Jiahao Wang ◽  
Heng Wang ◽  
Qiang Wang
Keyword(s):  
Vibration Isolation ◽  
Design Method ◽  
Sufficient Conditions ◽  
Disturbance Attenuation ◽  
Specific Kind ◽  
Design Algorithm ◽  
Geometry Design ◽  
Passive Vibration Isolation ◽  
The Relationship ◽  
Function Matrix

This paper presents the passive vibration isolation problem for a specific kind of Stewart Platform called flexure jointed hexapod (FJH). For purpose of analyzing the relationship between passive vibration isolation and parameters of the FJH, an existing dynamic model of the hexapod is re-cast appropriately to obtain the transfer function matrix from disturbance to generalized coordinates of the payload. Then, the system natural frequencies and the corresponding damping ratios are derived analytically. To guarantee the effective disturbance attenuation and isolation, a lower bound of the disturbance frequency with respect to the geometric parameters of the FJH is identified. Based on the identified sufficient conditions for disturbance isolation, a new design algorithm for geometry structure of the FJH and coefficients of the parallel spring-damping mechanism in struts is proposed. Finally, numerical simulation results are provided to demonstrate effectiveness of the proposed design algorithm.

scholarly journals A passive vibration isolation stack for LIGO: Design, modeling, and testing

1996 ◽  
Vol 67 (1) ◽  
pp. 208-214 ◽  
Author(s):  
Joseph Giaime ◽  
Partha Saha ◽  
David Shoemaker ◽  
Lisa Sievers
Keyword(s):  
Vibration Isolation ◽  
Passive Vibration Isolation

Experimental Study on the Performance of the Laminated Steel Isolators

2013 ◽  
Vol 423-426 ◽  
pp. 1603-1607
Author(s):  
Yao Guo Xie ◽  
Ping He ◽  
Xian Qiang Qu ◽  
Hong Bin Cui
Keyword(s):  
Experimental Study ◽  
Vibration Isolation ◽  
Dynamic Stiffness ◽  
Damping Ratio ◽  
Dynamic Performance ◽  
Performance Testing ◽  
Stiffness Ratio ◽  
Static Stiffness ◽  
Comparison Of The Results

Through the analysis and comparison of the results of static and dynamic performance testing of a series of laminated steel pieces isolators used in the vibration isolation of warships, in the number and thickness of laminated steel pieces of the same circumstances, laminated steel arc and preload of test samples had a certain impact on the values ​​of static stiffness, dynamic stiffness, damping ratio as well as dynamic and static stiffness ratio.

scholarly journals Experimental Validation of Fly-Wheel Passive Launch and On-Orbit Vibration Isolation System by Using a Superelastic SMA Mesh Washer Isolator

2017 ◽  
Vol 2017 ◽  
pp. 1-16 ◽  
Author(s):  
Seong-Cheol Kwon ◽  
Mun-Shin Jo ◽  
Hyun-Ung Oh
Keyword(s):  
Vibration Isolation ◽  
Application Form ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Static Tests ◽  
Resolution Observation ◽  
Passive Vibration Isolation ◽  
Basic Characteristics ◽  
Vibration Isolation Performance ◽  
Isolation Performance

On-board appendages with mechanical moving parts for satellites produce undesirable micro-jitters during their on-orbit operation. These micro-jitters may seriously affect the image quality from high-resolution observation satellites. A new application form of a passive vibration isolation system was proposed and investigated using a pseudoelastic SMA mesh washer. This system guarantees vibration isolation performance in a launch environment while effectively isolating the micro-disturbances from the on-orbit operation of jitter source. The main feature of the isolator proposed in this study is the use of a ring-type mesh washer as the main axis to support the micro-jitter source. This feature contrasts with conventional applications of the mesh washers where vibration damping is effective only in the thickness direction of the mesh washer. In this study, the basic characteristics of the SMA mesh washer isolator in each axis were measured in static tests. The effectiveness of the design for the new application form of the SMA mesh washer proposed in this study was demonstrated through both launch environment vibration test at qualification level and micro-jitter measurement test which corresponds to on-orbit condition.

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