Session: 02-03-01: Studies in Aerospace Structural Dynamics

Paper Number: 105883

105883 - Tunable Ultra-Low Frequency Isolator With Quasi-Zero Stiffness Metamaterials 

Vibration isolation is crucial for the scientific instruments with the stringent requirement of precision and high sensitivity of disturbance, especially, for the experiments in this microgravity environment, such as the ultracold atom interferometry and electrostatic space accelerometers, etc. To reduce the micro-oscillations at low frequencies, the isolators with the quasi-zero stiffness (QZS) and nonlinear characteristics have been drawn a great attention. Especially, the structures with the potential of elastic buckling, such as a curved beam or thin-walled dome, provide the promising solutions to realize a QZS isolator, rather than the traditional mechanism of combining the positive and negative stiffness with a large occupied volume. Mechanical metamaterials with tunable microstructure and programmable properties show an ingenious way to exhibit the QZS characteristics.

By patterning the QZS units with curved beams, a novel mechanical metamaterial is proposed in this paper. Firstly, the QZS unit on the basis of Euler beam with a cosine configuration is modeled. The analytical force-displacement relationship is investigated based on the assumption of buckling at the controlled low-order mode. The dynamics response of one QZS unit is explored analytically based on the Multi-Harmonic Balance Method. Then, the periodic metastructure with both horizonal and vertical patterns are constructed. The geometric parameters and overall response of QZS metamaterials are investigated. Furthermore, the effect of the structural damping, excitation amplitude and prescribed displacement on the transmission characteristics are examined. At last, the analytical results are verified by the finite element method. This work provides a novel way to design a QZS vibration isolator with elastic buckling structures for the ultra-low frequency isolation.

Presenting Author: Keyan Huo University of Chinese Academy of Sciences

Presenting Author Biography: Keyan Huo is a Phd candiate majoring in aerospace engineering and his research interests are in the field of structural dynamics and mechanical metastructures.

Authors:

Keyan Huo University of Chinese Academy of Sciences
Zihao Yuan University of Chinese Academy of Sciences
Ruinan Mu University of Chinese Academy of Sciences
Ke Wang University of Chinese Academy of Sciences
Haifeng Zhao University of Chinese Academy of Sciences