Lightweight Powered Prosthesis for above-knee amputees

项目总结 在接受膝盖以上截肢手术的40万美国人中，大多数人不能以不同的速度行走，而且 用他们指定的假体安全地穿越环境障碍[4]。这种有限的功能移动性 严重影响他们的独立性，并导致继发性健康问题，如背痛、骨关节炎、 和抑郁[5]。有动力的假体有可能通过提供能量为 在坡道或楼梯上攀登或从坐着的位置站起来，并通过改善行走稳定性和脚部 通行证。然而，可用的供电设备旨在满足年轻、强壮的人的需求 由于创伤而失去肢体的人，他们已经可以实现完全的社区行走 有可用的被动假体。 该提案的目标是确定提高活动水平所需的关键假体技术。 膝盖以上截肢者的比例从受限(K2)到社区(K3)救护车。我们的中心假设是 轻量级动力假体可以促进向变速行走的过渡和谈判 环境障碍(K3级)适用于目前在K2上端功能的截肢者 水平。我们之前的工作已经制造出第一个动力膝关节和脚踝假体[11]-[15]来结合 无源设备的轻量级(约5.5磅)，发电能力相当于电动假肢(约400瓦) [16]-[18]。此外，我们还开发了一种创新的控制框架，可以自动同步 在调节能量的同时，随着残肢的移动，动力假体关节的移动 基于行走速度的注射[19]。这些新的轻量级假体技术已经初步问世 与身体健全的受试者和年轻的创伤性膝上截肢者(K3-K4级)水平行走进行验证 [20]并以可变速度倾斜地面，以及上下楼梯[12]。而且，我们初步的 通过对三个K2以上受试者的实验，验证了该方法的可行性。 这项拟议研究的基本原理是，了解轻量级机器人技术如何做出贡献 功能移动性将使假体的创新设计和处方能够满足特定需求 改善血管障碍和老年截肢者的生活质量，从而改善医疗保健、行动能力和生活质量。 这一贡献是显著的，因为轻质动力假体有可能延长寿命。 并极大地提高多达100万名下肢截肢者的生活质量-预计这一群体 到2050年翻一番。我们的方法是创新的，因为它利用了一种新的假肢技术，与 在不牺牲功率和扭矩产生能力的情况下，现有被动假体的轻量化 首次满足血管功能障碍患者的具体需求。总体而言，这项工作有望提供 全面了解导致骨折的工程、生物力学和临床因素 截肢患者功能性步态能力从受限到社区步行能力的提高。

Project summary Most of the 400,000 Americans living with an above-knee amputation [3] cannot walk at variable speeds and safely negotiate environmental barriers with their prescribed prostheses [4]. This limited functional mobility severely affects their independence and results in secondary health problems, such as back pain, osteoarthritis, and depression [5]. Powered prostheses have the potential to address these problems by providing energy for climbing on ramps or stairs or standing up from a seated position, and by improving walking stability and foot clearance. However, available powered devices are designed to accommodate the needs of young, strong people, who overwhelmingly lose their limb due to trauma and can already achieve full community ambulation with available passive prostheses. The objective of this proposal is to identify key prosthesis technologies required to improve the mobility level of above-knee amputees form limited (K2) to community (K3) ambulators. Our central hypothesis is that a lightweight powered prosthesis can facilitate a transition into variable-speed ambulation and the negotiation of environmental barriers (K3 level) for those amputee patients who currently function at the upper end of the K2 level. Our previous work has produced the first powered knee and ankle prosthesis [11]–[15] to combine the lightness of a passive device (~5.5 lbs) with the power generation capability of a powered prosthesis (~400 W) [16]–[18]. In addition, we have developed an innovative control framework that automatically synchronizes the movement of the powered prosthesis joints with the movement of the residual leg, while modulating energy injection based on walking speed [19]. These novel lightweight prosthesis technologies have been preliminary validated with able-bodied subjects and young traumatic above-knee amputees (K3-K4 level) walking on level [20] and inclined ground at variable speeds, and climbing up and down stairs [12]. Moreover, our preliminary experiments with three K2 above-knee subjects demonstrate the feasibility of the proposed approach. The rationale for the proposed research is that understanding how lightweight robotic technologies contribute to functional mobility will enable innovative design and prescription of prostheses that address the specific needs of dysvascular and geriatric amputees, resulting in better healthcare, mobility, and quality of life. This contribution is significant because lightweight powered prostheses have the potential to extend longevity and to dramatically improve quality of life for up to a million lower-limb amputees—a population expected to double by 2050. Our approach is innovative because It leverages on a novel prosthesis technology that matches the lightness of available passive prostheses without sacrificing power and torque generation capability to address the specific needs of dysvascular patients for the first time. Cumulatively, this work is expected to provide a comprehensive understanding of the engineering, biomechanical, and clinical factors that contribute to the improvement of functional gait ability of amputee patients from limited to community ambulators.