NRI-Small: Chemo-Fludic Sleeve Muscle-Actuated Robotic Below-Knee Prostheses

描述（由申请人提供）：拟议的项目旨在开发一种紧凑且重量轻的机器人假体，目的是显著提高40万经胫骨（即，膝下，BK）截肢者在美国。在人类运动中，踝关节扮演着重要的能量角色，并且比膝盖和臀部提供更多的正能量。然而，在大多数现有的BK假体中，假体踝关节是能量被动的，仅在使用中存储和耗散能量。不能产生电力显著地损害了假肢为截肢者用户恢复运动功能的能力。临床研究表明：与健康受试者相比，佩戴被动BK假肢的截肢者表现出不对称的步态运动学，消耗的能量明显更多。为了解决这个问题，研究人员将探索一种创新的化学流体套筒肌肉驱动系统来为BK假体提供动力。两个关键要素构成了这一新系统的基础：（1）套筒肌肉致动器，一种创新的肌肉致动器，具有非常高的功率密度（至少比直流电机高十倍）;（2）高能量密度气动供应，能够在高度紧凑的包装内存储大量能量。通过这种高性能驱动系统，假肢预计将满足人类运动所带来的苛刻功率要求，同时最大限度地减少假肢重量和高度，以扩大可以从新型动力BK假肢中受益的截肢者群体。驱动技术的突破将与一种新的意图识别和运动控制算法相辅相成，预计该算法将以高度交互的方式提供用户所需的运动。该控制系统基于用户的推断的运动意图来识别期望的运动模式，并且通过基于阻抗的运动控制器来生成期望的关节扭矩命令，该基于阻抗的运动控制器使得能够在用户和假体之间进行物理交互。将进一步测试机器人假体和相应的控制系统，以表征其相对于最先进的被动BK假体的生物力学受益。

DESCRIPTION (provided by applicant): The proposed project aims to develop a compact and light-weight robotic prosthesis, with the objective of significantly enhancing the health and life quality of the 400,000 transtibial (i.e., below-knee, BK) amputees in the United States. In human locomotion, the ankle plays an important energetic role, and supplies substantially more positive power than the knee and hip. However, in the majority of existing BK prostheses, the prosthetic ankle joints are energetic passive, only storing and dissipating energy in use. The inability to generate power significantly impairs the prosthesis' capability of restoring the locomotive functions for the amputee user. Clinical studies indicate:that amputees wearing passive BK prostheses exhibit asymmetric gait kinematics and expend significantly more energy in comparison with healthy subjects. To address this issue, the investigators will explore an innovative chemo-fluidic sleeve muscle actuation system to power the BK prostheses. Two key elements form the basis of this new system: (1) Sleeve muscle actuator, an innovative muscle actuator with very high power density (at least ten times higher than DC motor); (2) Highenergy- density pneumatic supply, which is able to store a large amount of energy within a highly compact package. With this high-performance actuation system, the prosthesis is anticipated to meet the demanding power requirements imposed by the human locomotion, while minimizing the prosthesis weight and height to enlarge the amputee population that can benefit from the new powered BK prosthesis. The breakthrough in actuation technology will be complemented with a novel intent recognition and motion control algorithm, which is anticipated to provide the user's desired motion in a highly interactive manner. This control system identifies the desired locomotive pattern based on the user's inferred motion intent, and generates the desired joint torque command though ah impedance-based motion controller that enables physical interaction between the user and the prosthesis. The robotic prosthesis and the corresponding control system will be further tested to characterize its biomechanical benefits relative to state-of-the-art passive BK prostheses.