Article
Acoustics
Hongfei Zhu, Timothy F. Walsh, Bradley H. Jared, Fabio Semperlotti
Summary: This study discusses the design and application of a nonlocal elastic metasurface for achieving broadband passive vibration isolation in a complex structural assembly. The experimental results confirm the significant vibration isolation capabilities of the nonlocal metasurface, even under non-ideal incidence conditions, extending the validity of the results. Additionally, the study demonstrates that a planar metasurface can be morphed into a curved interface while maintaining full wave control capabilities.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Engineering, Mechanical
Feng Liu, Pengtao Shi, Yanlong Xu, Liyun Cao, Yizhou Shen, Zhichun Yang
Summary: The study focuses on the design of a single-phase circular meta-slab with subunits of different thicknesses to achieve total reflection of flexural waves and its application in vibration isolation. The theoretical analysis and numerical demonstrations confirm the effectiveness of the design in omnidirectional vibration isolation for practical engineering applications.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Chemistry, Physical
Jing Zeng, Wen Fan, Kangyu Jia, Shuhua Tu, Limin Wu
Summary: A novel retroreflective structural color film (RSCF) based on interference and total internal reflection (TIR) was reported. The film consists of a microscale polymer hemisphere array, displaying different colors under coaxial and noncoaxial illumination and observation. Additionally, an elastic polyurethane-based RSCF can exhibit dynamically changing colors during uniaxial tensile/compressive deformation.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Physics, Applied
Fei-Yu Liu, Na-Li Zhang, Hao-Wen Dong, Fa-Jie Wang, Sheng-Dong Zhao
Summary: A kind of broadband elastic wave coding metasurfaces is proposed in this paper. The metastructure unit designed by topology optimization is used as logical unit 1, and the pure plate is set as logical unit 0. The phase difference of the transmitted longitudinal wave between two units is introduced as the objective function in optimization. By coding the logical units, the designed metasurface can control the elastic wave between frequencies of 20.4 and 23.6 kHz, and wave performances such as beam focusing and splitting are achieved. The experimental results of the designed metasurface are in good agreement with numerical simulations. Therefore, our design has potential applications in the fields of engineering such as nondestructive testing.
APPLIED PHYSICS LETTERS
(2023)
Article
Acoustics
M. Utku Demir, Cetin Yilmaz
Summary: This study introduces a modular vibration isolator design that allows the adjustment of horizontal stiffness in three axes by changing compressive forces on leg modules. The system utilizes a multi-string tensioning mechanism to change the axial compressive forces on all elastic stepped columns simultaneously. Experimental and modeling results show that the proposed isolator has a wide isolation bandwidth.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Chemistry, Multidisciplinary
Xiangsen Kong, Hao Li, Xubin Zhou, Xiujuan Xiang, Xing Shen
Summary: This study focuses on the passive vibration isolation design of satellite flywheels. By introducing the concept of an elastic boundary and optimizing the elastic boundary condition of the structural plate, the vibration isolation effect of the flywheel can be effectively enhanced.
APPLIED SCIENCES-BASEL
(2023)
Article
Multidisciplinary Sciences
Ruichao Zhu, Tianshuo Qiu, Jiafu Wang, Sai Sui, Chenglong Hao, Tonghao Liu, Yongfeng Li, Mingde Feng, Anxue Zhang, Cheng-Wei Qiu, Shaobo Qu
Summary: This paper introduces a fast and accurate method for designing functional metasurfaces based on transfer learning, which can generate metasurface patterns monolithically for specific functions with high design accuracy. The proposed inverse design paradigm provides a efficient way for functional metasurface design and can be applied to establish a meta-atom library with full phase span.
NATURE COMMUNICATIONS
(2021)
Article
Optics
Jiahui Fu, Yuping Zhang, Zhongxin Dou, Zhihu Yang, Meng Liu, Huiyun Zhang
Summary: This paper proposes a deep-learning-assisted design method for 2-bit coding metasurfaces. It improves the accuracy limit of the basic model and increases the convergence ability of the model by nearly 10 times. The forward prediction accuracy of the deep-learning-assisted model is 98%, and the accuracy of inverse design results is 97%. It offers the advantages of an automatic design process, high efficiency, and low computational cost.
Article
Computer Science, Information Systems
Mustafa K. Taher Al-Nuaimi, William G. Whittow
Summary: This article presents the design of 1-bit metasurfaces for radar cross section (RCS) reduction over a wide frequency band. The metasurfaces are designed using a 2D QR code generator in MATLAB, allowing for efficient optimization of the phase distribution. The study shows that QR coded metasurfaces are effective in achieving more than 10-dB RCS reduction with low-level diffusive scattering patterns. Simulation and measurement results demonstrate that the proposed metasurfaces reduce backscattered energies and RCS by more than 10 dB for different polarizations over a frequency range of 60 GHz to 120 GHz.
Article
Materials Science, Multidisciplinary
Seung Yoon On, Hyemi Moon, Seong Yeon Park, Tae Woong Ohm, Wonvin Kim, Hyunsoo Hong, Seong Su Kim
Summary: In this study, a Roman-bridge-inspired metamaterial for vibration isolation is proposed that combines a geometrical nonlinear structure and band gap effect by arranging periodic materials in a semicircular arched structure. Finite element analysis and band diagram analysis are conducted to verify the effectiveness of the periodic arch-structured metamaterial. The geometrical parameters of the metamaterial are optimized using a machine learning model, and the optimized structure is validated through numerical analysis and frequency response testing.
MATERIALS & DESIGN
(2022)
Article
Physics, Applied
Chun Min Li, Shengyuan Zhang, Haibo Chen, Wenjing Ye
Summary: As the most popular mechanism, the generalized Snell's law has been extensively used for designing metasurfaces that manipulate waves. However, it has been observed that the performance of these metasurfaces is not always determined solely by the generalized Snell's law, and sometimes the wave fields exhibit contradictory behavior. This study systematically investigates the generalized Snell's law for elastic waves through numerical simulations. The inherent assumptions of the law are examined, and the effects of various implementation issues on the metasurface performance are studied. The study also identifies and theoretically justifies the fundamental mechanism responsible for producing wave components that do not obey the generalized Snell's law, and provides design guidelines for improved metasurface performance.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Do-Hoon Kwon
Summary: A design technique for single-layer metasurfaces of planar and conformal profiles utilizing nonperiodic, irregular grids for meta-atom placement is presented. Meta-atoms are placed at the node positions in planar and conformal surface grids created by an unstructured mesher. They are represented by point dipoles using the discrete dipole approximation (DDA), and mutual coupling effects from neighboring resonators are accurately evaluated. Each meta-atom is individualized for representing a desired average current density over the corresponding cell area. Examples of fully reflecting metasurfaces using DDA-based individualized meta-atoms exhibit closer-to-ideal performance than identical meta-atoms on the same grid.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Guoqiang Li, Hongyu Shi, Jianjia Yi, Bolin Li, Anxue Zhang, Zhuo Xu
Summary: A transmission-reflection-integrated element and metasurface (MS) is proposed to manipulate the amplitudes, phases, and polarization states of electromagnetic waves in a full space. By introducing an amplitude-phase regulation structure to each element, the reflection and transmission can be controlled simultaneously under the same incident wave. The experimental results demonstrate that the proposed integrated element can generate deflective vortex beams with different values of topological charge in both the reflection and transmission modes.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Acoustics
Deshui Xu, Jun Lu, Kun Zhang, Pengzhou Li, Lei Sun
Summary: This manuscript presents an exact solution for the longitudinal vibrating characteristics of generally restrained nanorod structures with multiple internal elastic supports. By introducing artificial springs and setting restrained stiffness accordingly, the general boundary restraints are formulated. The study provides an effective method for predicting the longitudinal vibration characteristics of nanorods with complex boundary and coupling conditions.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Acoustics
Goran Pavic
Summary: This article provides an extended analysis of the fundamental relationship between the global stationary vibration of a structure and the supplied complex mechanical power. It suggests that the apparent loss factor can be substituted by the averaged physical loss factor and introduces an isolation strategy based on mobility approach for selecting vibration isolators. A case study is used to test the proposed strategy and three indicators are used for isolator selection, including the global kinetic energy estimate, the frequency-weighted net input power, and the RMS force transmitted to the isolated structure.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Materials Science, Multidisciplinary
Hongfei Zhu, Fabio Semperlotti
Article
Physics, Multidisciplinary
Hongfei Zhu, Fabio Semperlotti
PHYSICAL REVIEW LETTERS
(2016)
Article
Physics, Applied
Hongfei Zhu, Fabio Semperlotti
JOURNAL OF APPLIED PHYSICS
(2017)
Article
Physics, Applied
Hongfei Zhu, Fabio Semperlotti
PHYSICAL REVIEW APPLIED
(2017)
Article
Physics, Applied
H. Zhu, F. Semperlotti
JOURNAL OF APPLIED PHYSICS
(2014)
Article
Physics, Applied
F. Semperlotti, H. Zhu
JOURNAL OF APPLIED PHYSICS
(2014)
Article
Nanoscience & Nanotechnology
Hongfei Zhu, Fabio Semperlotti
Article
Acoustics
Hongfei Zhu, Timothy F. Walsh, Fabio Semperlotti
JOURNAL OF SOUND AND VIBRATION
(2019)
Article
Multidisciplinary Sciences
Hongfei Zhu, Sansit Patnaik, Timothy F. Walsh, Bradley H. Jared, Fabio Semperlotti
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Materials Science, Multidisciplinary
H. Zhu, F. Semperlotti
INTERNATIONAL JOURNAL OF SMART AND NANO MATERIALS
(2015)
Article
Materials Science, Multidisciplinary
Hongfei Zhu, Ting-Wei Liu, Fabio Semperlotti