Contact-Free Actuation Enabled by Acoustic Metasurfaces

这笔赠款将用于利用声波远程非接触激励物体的基础研究。物体的运动控制和操纵是科学和工程中的普遍挑战。传统的驱动机构通常需要物理系绳或板载能源，这在机器人、材料组装、生物工程和生物医学的实际应用中可能会很麻烦。由声波等波的辐射压力驱动可以是完全非接触的，但目前的技术仅限于较小的亚波长物体。为了克服这些限制，该项目将利用声波与被称为超表面的工程结构之间的相互作用。其主要思想是用表面图案包裹对象，这些表面图案被故意设计来控制激励波的动量变化，即控制激励的方向和强度，从而能够远程移动、操纵和操纵这些对象。科学研究将与教育和推广活动紧密结合在一起，包括旨在扩大参与并让学生接触超材料和机器人交叉点的科学和工程的动手演示。该项目的技术目标是发展对超表面控制的非接触式动力学的基础理解。通过使用变形表面图案，可以高保真和高分辨率地控制沿物体表面的每个位置的辐射压力。这项研究的目标是开发一个双向的、正向和反向的模型，在期望的对象动力学和元表面模式之间进行映射。通过结合波动物理分析和有限元模拟，该项目将确定适合作为非接触式驱动的构建块的新的亚表面拓扑结构。建模工作将通过制作和表征变形表面结构和桌面实验来证明其动态行为。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This grant will fund fundamental research on the remote and contactless actuation of objects with acoustic waves. Motion control and manipulation of objects present universal challenges in science and engineering. Conventional actuation mechanisms often require physical tethers or onboard energy sources, which can be cumbersome in practical applications in robotics, materials assembly, bioengineering, and biomedicine. Actuation by the radiation pressure of waves, such as acoustic waves, can be entirely contactless, but current techniques are limited to small, subwavelength objects. To overcome these limitations, this project will exploit the interaction of acoustic waves with engineered structures known as metasurfaces. The main idea is to envelop objects with surface patterns that are deliberately designed to control the momentum change of the actuating wave, that is, to control the direction and intensity of actuation, enabling to remotely move, steer, and manipulate these objects. The scientific research will be tightly integrated with education and outreach activities including hands-on demonstrations designed to broaden participation and expose students to science and engineering at the intersection of metamaterials and robotics.The technical objective of this project is to develop a foundational understanding of metasurface-controlled contactless dynamics. By utilizing metasurface patterns, it is possible to control the radiation pressure with high fidelity and high resolution at each location along the object’s surface. The objective of this research is to develop a bidirectional, forward and inverse, models that map between the desired object dynamics and metasurface patterns. By combining wave-physics analysis and finite-element simulations, this project will identify new metasurface topologies that are suitable as building blocks for contactless actuation. Modeling efforts will be supported by the fabrication and characterization of metasurface structures and tabletop experiments to demonstrate their dynamical behavior.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.