Designing soft engines and active solids

柔软的材料围绕着我们，组成我们。在现代经济中，从食品科学和化妆品中使用的凝胶到对运输至关重要的橡胶，软固体支撑着几个行业。最近在研究实验室中开发的一种奇特的软材料被称为活性物质，它是由能够自行移动的成分制成的。大多数对活性物质的研究都集中在活性流体上，以及最小尺度的运动如何引起大尺度的流动。在这个建议中，我专注于活性固体及其弹性，以设计新型的活性软材料。这项研究旨在回答的广泛问题是：“什么材料的性质是不允许在平衡，但可以使用活性物质创建？”合成软机器的设计在材料科学和机器人技术的交叉点上提出了一系列挑战。一个挑战是将传感器和致动器与变形、移动和执行有用功的弹性部件集成在一起。为了创造出高效的软机器，有必要了解这些活性材料的基本规律。这个令人兴奋的基础科学领域最近通过结合材料科学和非平衡物理学的工具取得了很多进展。该提案旨在解决在设计软机器的过程中遇到的挑战：如何使活性材料做有用的事情？为了应对这一挑战，该提案旨在制定关于如何从具有活性成分的材料中提取有用功的基本物理定律。一旦这些法律已经制定，他们可以用来构建一套设计原则的功能，有效的软机器。活性材料本质上是模块化的，因为它们由许多可互换的移动部件组成。从广义上讲，该提案研究领域的长期目标是改进目前的软设备设计，如人造器官和肢体以及可穿戴电子产品，例如通过创建更有效，更耐损伤或自我修复的有源组件。

Soft materials surround us and compose us. In the modern economy, soft solids underpin several industries from gels used in food science and cosmetics to rubber crucial to transportation. One exotic type of soft material recently developed in research labs is called active matter and is created from constituents that move themselves. Most of the research in active matter focuses on active fluids and how movement on the smallest scales can induce large-scale flow. In this proposal, I focus on active solids and their elasticity in order to design new types of active soft materials.The broad question that this research aims to answer is: ``What materials properties are disallowed in equilibrium, but can be created using active matter?'' The design of synthetic soft machines presents a set of challenges at the intersection of materials science and robotics. One challenge is to integrate sensors and actuators with elastic components that deform, move, and perform useful work. In order to create soft machines that are efficient, it is necessary to understand the fundamental laws governing such active materials. This exciting area of fundamental science has seen a lot of recent progress by combining the tools of materials science and non-equilibrium physics. This proposal aims to address a challenge encountered on the way to designing soft machines: how can one make an active material do something useful? In order to address this challenge, the proposal aims to formulate the fundamental physical laws about how useful work can be extracted from a material with active components. Once these laws have been formulated, they can be used to construct a set of design principles for functional, efficient soft machines. Active materials are inherently modular, because they are composed of many interchangeable moving parts. Broadly speaking, the long-term aim of the proposal's research area is to improve on the current design of soft devices such as artificial organs and limbs as well as wearable electronics, for example by creating active components that are more efficient, more damage resistant, or self-healing.