NRI: INT: COLLAB: Anthropomorphic Robotic Ankle Prosthesis with Programmable Materials

目前有200万美国人截肢；这些截肢大多是下肢。截肢是一个重大的改变生活的事件，对生活的许多方面都有压倒性的负面影响，甚至在受伤多年后。截肢手术的费用可能超过每人180万美元。大多数可用的假肢都是为了在平地行走时复制正常脚踝功能的某些方面而设计的。这些假肢使许多膝盖以下截肢的患者能够恢复基本的日常活动。然而，这些设备最适合平地行走，许多用户在其他重要任务中遇到困难，例如在斜坡、楼梯或不同的地形上行走。因此，本项目的总体目标是通过使新的假肢能够适应日常生活中常见的不同环境条件，来解决现有动力踝足假肢设计中的这一空白。所提出的踝足机构通过引入一种新的设计方法，显著提高了下肢动力假肢的可定制性。这个项目将研究在不同的行走场景下，人的脚踝僵硬度是如何变化的。研究小组将利用这些信息设计一种动力踝足假体，其性能更接近人类脚踝。为了做到这一点，将开发一种使用可编程材料的轻量级模块化假体。模块化的机械设计和控制方法产生了类似人类的特征，使更多不同长度截肢的用户能够使用这种假肢。此外，假体的性能将在动态环境中的真实活动中进行评估。这个项目的重点是截肢者的福祉。由此产生的灵活踝足假体将帮助截肢者改善他们的身体功能，工作和娱乐能力，从而帮助个人恢复受伤前的活动和生活质量。该项目的研究成果也可以应用于外骨骼、矫形器和康复机器人的先进功能。除了推进研究，本科生和研究生将参与研究活动，并将接受跨学科教育/创新/拓展经验。外展活动将使项目团队能够吸引不同的初高中学生参与科学和工程，特别是那些来自代表性不足的群体和低收入家庭的学生。该项目计划开发一种新型可定制的灵活踝足假肢，该假肢采用模块化设计，其阻抗调制与扭矩控制分离。这将通过配备一种新型的、最近开发的动力2自由度（DOF）踝足假体来实现，该假体由软可编程材料制成，具有增强机制。该项目的主要成果将是全面了解如何1)减少临床试验中观察到的踝足假体控制的复杂性，以及2)提高假体在现实活动中的性能，例如在不同轮廓，刚度和侧倾角的表面上行走和跑步。计划中的工作旨在解决机器人踝足假肢的可定制性问题，并通过改善截肢者的生活和工作质量来解决社会影响。本研究的主要目标是将脚踝的阻抗控制整合到一个由可编程材料组成的机械模块中，以跟踪人体脚踝的二维阻抗。这项工作将进一步将阻抗调制与脚踝的2自由度扭矩控制相结合，以提供定制性，以便在扭矩控制调谐的同时，根据每个用户的需求定制灵活的假肢。该项目的研究人员假设，实时控制机器人踝足假体中的二维脚踝阻抗可以提高用户在不同轮廓、刚度和倾角的表面上行走时的性能和敏捷性。这些相互关联的研究重点将通过以下途径提供新的解决方案：1)对不同步态场景下的踝关节动力学建模；2)为2- dof机器人踝关节足假体配备可编程材料模块；3)对截肢者进行广泛的评估实验。了解在下肢假肢行走过程中对二维踝关节阻抗的控制和适应的影响，将对辅助机器人领域大有裨益，因为它可以为动力假肢、外骨骼和康复设备的设计和控制提供指导。除了推进研究，本科生和研究生将参与研究活动，并将接受跨学科教育/创新/拓展经验。外展活动将使项目团队能够吸引不同的初高中学生，特别是那些来自代表性不足的群体和低收入家庭的学生。该项目的研究成果将通过出版物、软件共享和技术商业化进行传播。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。

There are currently 2 million Americans living with an amputation; the majority of those amputations are of the lower limbs. Leg amputation is a significant life-altering event that has an overwhelmingly negative effect on many aspects of life, even years after the injury. Leg amputation can cost in excess of $1.8 million per individual. Most available prostheses are designed to replicate some aspects of normal ankle function during level-ground walking. These prostheses allow many individuals with below-knee amputation to return to basic daily activities. However, these devices are best suited for level-ground walking and many users experience difficulties during other important tasks, such as walking on slopes, stairs, or different terrains. Therefore, the general aim of this project is to address this gap in the design of existing powered ankle-foot prostheses by enabling new prosthetics that adapt to different environmental conditions commonly found in daily life. The proposed ankle-foot mechanism significantly enhances the customizability of lower leg-powered prostheses by introducing a new design approach. This project will study how the human ankle stiffness changes during different walking scenarios. The research team will use this information to design a powered ankle-foot prosthesis with properties more similar to the human ankle. In order to do so, a lightweight and modular prosthesis that uses programmable material will be developed. The modular mechanical design and control approach generates human-like characteristics and enables a larger set of users with different lengths of amputated legs to use this prosthesis. Moreover, the prosthesis' performance will be evaluated during real-world activities in dynamic environments. The focus of this project is on amputees' well-being. The resulting agile ankle foot prosthesis will help amputees improve their physical function, ability to work, and recreation, thus helping individuals return to the activities and quality of life they had prior to injury. The research findings from this project can also be applied to advance functions of exoskeletons, orthotics, and rehabilitation robots. In addition to advancing research, undergraduate and graduate students will be involved in research activities and will receive interdisciplinary education/innovation/outreach experiences. Outreach activities will allow the project team to engage diverse middle and high school students in science and engineering, especially those from underrepresented groups and low-income families. This project plans a new class of customizable agile ankle-foot prosthesis that is modular in design and has its impedance modulation decoupled from its torque control. This will be achieved by equipping a novel and recently developed powered 2-degrees of freedom (DOF) ankle-foot prosthesis with an augmented mechanism built from soft programmable material. The primary outcomes of this project will be a comprehensive understanding of how to 1) reduce the complexity of the control of ankle-foot prostheses, as observed in clinical trials, and 2) enhance prosthesis performance in real-world activities, such as walking and running on surfaces with different profiles, stiffness, and lateral inclinations. The planned work aims to address customizability issues of robotic ankle foot prostheses and address societal impact by improving amputees' quality of life and work. The main goal of this study is to consolidate the impedance control of the ankle to a mechanical module comprised of programmable material to follow the 2-D human ankle impedance. The effort will further integrate the impedance modulation with 2-DOF torque control of the ankle to provide the customizability required for tailoring an agile prosthesis to each user's need in parallel to the torque control tuning. The project researchers hypothesize that real-time control of the two-dimensional ankle impedance in a robotic ankle-foot prosthesis can improve the performance and the agility of the user during walking on surfaces with different profiles, stiffness, and inclinations. The interconnected research thrusts will provide the opportunity to offer a new solution through 1) modeling the ankle dynamics in different gait scenarios, 2) equipping a 2-DOF robotic ankle-foot prosthesis with a programmable material module, and 3) performing extensive evaluation experiments with amputees. Understanding the effect of the control and adaptation of the 2-D ankle impedance during walking with a lower extremity prosthesis will be significantly beneficial for the field of assistive robotics because it can provide guidelines for the design and control of powered prostheses, exoskeletons, and rehabilitation devices. In addition to advancing research, undergraduate and graduate students will be involved in research activities and will receive interdisciplinary education/innovation/outreach experiences. Outreach activities will allow the project team to engage diverse middle and high school students, especially those from underrepresented groups and low-income families. The findings from this project will be disseminated through publications, software sharing, and technology commercialization.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.