Reconfigurable Metasurfaces for Controlling Elastic Wavefront

用于控制弹性波前的可重构超表面

• 批准号: 1933436
• 负责人: Serife Tol
• 金额: $ 35.64万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1933436&HistoricalAwards=false
• 关键词: Reconfigurable; Metasurfaces; Controlling; Elastic; Wavefront

Elastic metamaterials and phononic crystals are artificially structured composite materials that can manipulate and control elastic waves. While they are proven to be useful in many ultrasonic applications, their wave functionality is limited to the low frequency regime. Since a significant amount of energy is carried by low frequency waves propagating in mechanical or civil systems, it is crucial to develop compact structures enabling broadband control of low frequency elastic waves without the need for further structural modifications. This grant will support research that will answer how to effectively tailor low frequency elastic waves within a small footprint and advance the state-of-art via reconfigurable metasurface concepts. The reconfigurable metasurfaces will enable broadband wave focusing and high-power energy harvesters converting low frequency vibrations into usable electricity, overcoming the energy related limitations of the wireless sensor networks. This award supports fundamental research and advances applications in mechanical, civil, and aerospace systems to achieve next-generation wave devices that are compact and easy to integrate within existing structures. Therefore, results from this research will benefit the U.S. economy and broader society. The integrated education program will also help broaden participation of underrepresented groups in research and features a K-12 outreach module for the Girls in Science and Engineering Camp at the U-M.The research goal of this is to manipulate and control low frequency elastic waves (~hundreds of Hz) via compact reconfigurable metasurfaces which can adapt to environmental conditions to achieve greater dynamic wave functionalities such as steering and focusing in a broadband frequency range. This research will introduce active elastic metasurfaces and nonlinear elastic metasurfaces which will be tuned by external electrical and mechanical loads, respectively. The key idea is to leverage the linear/nonlinear dynamics of the elastic/electro-elastic unit cells and tailor elastic wavefronts over a broad range of frequencies using the existing structure. A theoretical framework will be established to implement the required phase gradient for achieving desired dynamic wavefront shapes. While manipulating the elastic wave propagation by tailoring the refraction properties of the metasurface, wave reflections will be minimized to ensure maximum wave transmission through the active/nonlinear metasurface layer. The research will create next-generation metasurfaces to modulate low frequency wavefronts in high impact applications in mechanical, civil, and aerospace systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

弹性超材料和声子晶体是可以操纵和控制弹性波的人工结构复合材料。虽然它们在许多超声波应用中被证明是有用的，但它们的波功能仅限于低频范围。由于在机械或民用系统中传播的低频波携带了大量的能量，因此开发紧凑的结构是至关重要的，它可以在不需要进一步修改结构的情况下实现低频弹性波的宽带控制。这笔拨款将支持研究如何在小范围内有效地定制低频弹性波，并通过可重构超表面概念推进最新技术。可重构的超表面将使宽带波聚焦和高功率能量收集器能够将低频振动转化为可用的电力，克服无线传感器网络的能量限制。该奖项支持机械、民用和航空航天系统的基础研究和先进应用，以实现紧凑且易于集成到现有结构中的下一代波器件。因此，这项研究的结果将有利于美国经济和更广泛的社会。综合教育项目还将有助于扩大未被充分代表的群体对研究的参与，并为密歇根大学的“科学与工程女孩营”（Girls in Science and Engineering Camp）提供一个K-12拓展模块。这项研究的目标是通过紧凑的可重构超表面来操纵和控制低频弹性波（~数百赫兹），这种超表面可以适应环境条件，以实现更大的动态波功能，例如在宽带频率范围内转向和聚焦。本研究将引入主动弹性超表面和非线性弹性超表面，它们将分别由外部电载荷和机械载荷调谐。关键思想是利用弹性/电弹性单元单元的线性/非线性动力学，并使用现有结构在广泛的频率范围内定制弹性波前。将建立一个理论框架来实现所需的相位梯度，以实现所需的动态波前形状。在通过调整超表面的折射特性来控制弹性波的传播时，波的反射将被最小化，以确保波通过有源/非线性超表面层的最大传输。该研究将创建下一代超表面，以调制机械、民用和航空航天系统中高冲击应用中的低频波前。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Piezoelectric metastructures for simultaneous broadband energy harvesting and vibration suppression of traveling waves

• DOI: 10.1088/1361-665x/ac04c3
• 发表时间: 2021-07-01
• 期刊: SMART MATERIALS AND STRUCTURES
• 影响因子: 4.1
• 作者: Lin, Z.;Al Ba'ba'a, H.;Tol, S.
• 通讯作者: Tol, S.

Elastic Metasurfaces for Full Wavefront Control and Low-Frequency Energy Harvesting

• DOI: 10.1115/1.4050275
• 发表时间: 2021-12
• 期刊: Journal of Vibration and Acoustics
• 作者: Zhen Lin;S. Tol

Anomalous wavefront control via nonlinear acoustic metasurface through second-harmonic tailoring and demultiplexing

• DOI: 10.1063/5.0101076
• 发表时间: 2022-05
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: Zhen Lin;Yuning Zhang;Kon-Well Wang;S. Tol

Nonlinear acoustic metasurface for simultaneous higher-harmonic generation and demultiplexing

• DOI: 10.1117/12.2612932
• 发表时间: 2022-04
• 作者: Zhen Lin;Yuning Zhang;Kon-Well Wang;S. Tol

Electroelastic metasurface with resonant piezoelectric shunts for tunable wavefront control

• DOI: 10.1088/1361-6463/acbd5f
• 发表时间: 2022-12
• 期刊: Journal of Physics D: Applied Physics
• 作者: Z. Lin;S. Tol