Agrawal Sunil K, Banala Sai K, Fattah Abbas, Sangwan Vivek, Krishnamoorthy Vijaya, Scholz John P, Hsu Wei-Li
Mechanical Systems Laboratory, Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, USA.
IEEE Trans Neural Syst Rehabil Eng. 2007 Sep;15(3):410-20. doi: 10.1109/TNSRE.2007.903930.
The gravity balancing exoskeleton, designed at University of Delaware, Newark, consists of rigid links, joints and springs, which are adjustable to the geometry and inertia of the leg of a human subject wearing it. This passive exoskeleton does not use any motors but is designed to unload the human leg joints from the gravity load over its range-of-motion. The underlying principle of gravity balancing is to make the potential energy of the combined leg-machine system invariant with configuration of the leg. Additionally, parameters of the exoskeleton can be changed to achieve a prescribed level of gravity assistance, from 0% to 100%. The goal of the results reported in this paper is to provide preliminary quantitative assessment of the changes in kinematics and kinetics of the walking gait when a human subject wears such an exoskeleton. The data on kinematics and kinetics were collected on four healthy and three stroke patients who wore this exoskeleton. These data were computed from the joint encoders and interface torque sensors mounted on the exoskeleton. This exoskeleton was also recently used for a six-week training of a chronic stroke patient, where the gravity assistance was progressively reduced from 100% to 0%. The results show a significant improvement in gait of the stroke patient in terms of range-of-motion of the hip and knee, weight bearing on the hemiparetic leg, and speed of walking. Currently, training studies are underway to assess the long-term effects of such a device on gait rehabilitation of hemiparetic stroke patients.
位于纽瓦克的特拉华大学设计的重力平衡外骨骼由刚性连杆、关节和弹簧组成，这些部件可根据佩戴者腿部的几何形状和惯性进行调整。这种被动式外骨骼不使用任何电机，其设计目的是在人体腿部关节的运动范围内减轻重力负荷。重力平衡的基本原理是使腿部 - 机器组合系统的势能不随腿部的构型而变化。此外，可以改变外骨骼的参数，以实现从0%到100%的规定重力辅助水平。本文报道结果的目的是对人体佩戴这种外骨骼时步行步态的运动学和动力学变化进行初步定量评估。运动学和动力学数据是在四名健康人和三名中风患者佩戴这种外骨骼时收集的。这些数据是根据安装在外骨骼上的关节编码器和接口扭矩传感器计算得出的。这种外骨骼最近还用于一名慢性中风患者的为期六周的训练，在此期间重力辅助从100%逐渐降低到0%。结果表明，中风患者的步态在髋关节和膝关节的运动范围、偏瘫侧腿部的负重以及步行速度方面有显著改善。目前，正在进行训练研究，以评估这种设备对偏瘫中风患者步态康复的长期影响。
