CAREER: Artificial Muscle Based on Dielectric Elastomers for Dexterous and Compliant Prostheses

这个学院早期职业发展（Career）项目的主要目标是实现具有类似天然肌肉的机械和动态特性的人造肌肉。特别是，该项目考虑使用一类称为介电弹性体（DEs）的材料，这种材料具有可与生物肌肉相媲美的顺应性、弹性和单位面积的力。像生物肌肉一样，这些材料可以自我感知，允许精确控制收缩或伸展，而不需要视觉反馈或其他辅助感知方案。该项目的最终目标是使用基于de的人造肌肉实现灵巧、轻便和节能的假肢，与当前一代机械手臂的笨重和低效的电动机形成对比。该项目结合了仿生设计、设备制造、动态建模、传感和控制等方面。该项目的成功将有助于为大约200万因事故、自然灾害、战争、疾病或衰老而失去双手、手臂或腿的退伍军人和平民提供负担得起、可靠和舒适的假肢。该项目还将培训下一代劳动力，掌握基于智能材料和结构的动态建模、控制和设备制造技能。吸引学生进入这一研究领域的活动将提高科学、技术、工程和数学（STEM）学科的入学率。这项研究的长期目标是开发轻量级、柔顺性和自传感的DEs，以模拟机器人辅助应用中生物肌肉的驱动和传感。实现这一目标的第一步是获得仿生设计、建模、自我感知和控制策略，用于假手应用中的DE执行器。本项目将强调以下核心目标：1)构建一种新型的人造肌肉结构，由管状DE人造肌肉附着在碳纤维人造肌腱上；2)推导了一个低阶物理模型，该模型捕获了DE执行器的非线性弹性和应变相关电阻抗；(3)利用执行器对应变相关电阻抗的自感知实现灵敏鲁棒的非线性状态观测器；(4)推导了一种状态边界回避控制策略，以保护DE执行器不受损坏；和(5)建立一个de启用假手，以演示灵巧的操作与高效，兼容的驱动。

This Faculty Early Career Development (CAREER) project has the main goal of realizing artificial muscle with mechanical and dynamic properties similar to natural muscle. In particular, this project considers the use of a class of materials called dielectric elastomers (DEs) that have compliance, resilience, and force per area comparable to biological muscles. Like biological muscles, these materials can be self-sensing, allowing precise control of contraction or extension without needing visual feedback or other auxiliary sensing schemes. The ultimate goal of the project is to achieve dexterous, lightweight, and energy-efficient prostheses using DE-based artificial muscles, in contrast to the heavy and inefficient electric motors of the current generation of robotic arms. The project incorporates aspects of bio-inspired design, device fabrication, and dynamic modeling, sensing, and control. The success of this project will help provide affordable, reliable, and comfortable prostheses to the estimated two million military veterans and civilians who have lost hands, arms, or legs to accidents, natural disasters, wars, diseases, or aging. This project will also train the next-generation workforce with skills in the dynamic modeling, control, and fabrication of devices based on smart materials and structures. Activities to attract students to this area of research will improve enrollment in science, technology, engineering, and mathematics (STEM) disciplines.The long-term goal of this research is to develop lightweight, compliant, and self-sensing DEs to emulate the actuation and sensing of biological muscles for robotic assistive applications. A first step towards this goal is to obtain bio-inspired design, modeling, self-sensing, and control strategies for DE actuators in a prosthetic hand application. This project will emphasize the following core goals: 1) create a novel artificial muscle structure consisting of a tubular DE artificial muscle attached to carbon fiber artificial tendons; 2) derive a low-order physics-based model capturing the nonlinear elasticity and strain-dependent electrical impedance of the DE actuator; (3) implement a sensitive and robust nonlinear state observer using actuator self-sensing of the strain-dependent electrical impedance; (4) derive a state-boundary avoidance control strategy to protect the DE actuator from damage; and (5) build a DE-enabled prosthetic hand to demonstrate dexterous manipulation with efficient, and compliant actuation.