ERI: Exploiting Dynamic Origami for Reconfigurable and Versatile Control of Acoustic Waves

这项工程研究启动（ERI）拨款将资助研究，以提高通过民用基础设施、机械机械和航空航天系统控制声音传播的灵活性，包括声学成像、缺陷检测和噪声控制方面的应用，从而促进科学进步，促进国家繁荣和福利。声学超表面是一种二维薄的人造材料，它对声波的散射具有非凡的控制能力。直到最近，这样的元表面还具有难以实时调优的固定配置，从而限制了它们的潜在使用和性能。最近，可调谐、可重构和可编程声学超表面有望实现高效、智能的声波控制，但现有的解决方案存在复杂的调谐机制、使用有源元件和低效率的问题。该项目将通过展示新的简单机制来克服这些限制，利用折纸原理设计的柔性结构来实现可重构声波控制，其折叠几何形状可以实时调制。虽然折纸原理已广泛应用于机器人，软材料和柔性电子，动态折纸和声波控制之间的关系在很大程度上尚未探索。这项研究产生的知识和工具将使下一代可重构的基于波的设备能够适应不断变化的环境和性能目标。旨在吸引新一代学生参与STEM教育和研究的活动包括面向K-12学生的外展计划，以及广泛计划的本科生参与团队技术研究项目。本研究旨在为实际理解折纸结构在变形过程中形状、周期和尺寸的动态变化及其对声波传播的影响做出基础贡献。通过建立一个理论和计算框架来表征和预测声波与动态折纸结构的相互作用，通过开发设计策略来实现具有目标功能的动态折纸结构的特定应用合成，并通过研究不同的调谐机制来实现这一结果。实验验证和测试将在利用理论分析强调的折纸原理的原型可重构声学超表面上进行。这样的实验实现将用于演示波转向和波聚焦功能典型的传感，通信，成像和能量收集应用。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。

This Engineering Research Initiation (ERI) grant will fund research that enables increased flexibility in the control of sound propagating through civil infrastructure, mechanical machinery, and aerospace systems, including for applications in acoustic imaging, defect detection, and noise control, thereby promoting the progress of science and advancing the national prosperity and welfare. Acoustic metasurfaces are two-dimensional thin artificial materials that are empowered with extraordinary control over the scattering of sound waves. Until recently, such metasurfaces had fixed configurations that were difficult to tune in real time, thereby limiting their potential use and performance. A recent focus on tunable, reconfigurable, and programmable acoustic metasurfaces promises efficient and smart control of sound waves, but existing solutions suffer from sophisticated tuning mechanisms, use of active elements, and poor efficiency. This project will overcome these limitations by demonstrating new and simple mechanisms for reconfigurable acoustic wave control using flexible structures designed by origami principles, whose folded geometry may be modulated in real time. Although origami principles have been widely used in robotics, soft materials, and flexible electronics, the relationship between dynamic origami and acoustic wave control has been largely unexplored. The knowledge and tools generated by this research will enable the next generation of reconfigurable wave-based devices that are adaptive to changing environments and performance objectives. Activities aiming to engage new generations of students in STEM education and research include outreach programs to K-12 students and extensive planned participation of undergraduate students in team-based technical research projects.This research aims to make fundamental contributions to a practical understanding of how the shape, periodicity, and size of origami structures change dynamically as they undergo deformation and the concomitant impact on acoustic wave propagation. It will achieve this outcome by building a theoretical and computational framework for characterizing and predicting acoustic wave interactions with dynamic origami structures, by developing design strategies that enable application-specific synthesis of dynamic origami structures with target functionalities, and by investigating different tuning mechanisms. Experimental validation and testing will be performed on prototype reconfigurable acoustic metasurfaces that leverage principles of origami highlighted by the theoretical analysis. Such experimental realization will be used to demonstrate wave steering and wave focusing functionalities typical of sensing, communication, imaging, and energy harvesting applications.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.