John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA.
Sci Robot. 2017 Jan 18;2(2). doi: 10.1126/scirobotics.aah4416.
When defining requirements for any wearable robot for walking assistance, it is important to maximize the user's metabolic benefit resulting from the exosuit assistance while limiting the metabolic penalty of carrying the system's mass. Thus, the aim of this study was to isolate and characterize the relationship between assistance magnitude and the metabolic cost of walking while also examining changes to the wearer's underlying gait mechanics. The study was performed with a tethered multiarticular soft exosuit during normal walking, where assistance was directly applied at the ankle joint and indirectly at the hip due to a textile architecture. The exosuit controller was designed such that the delivered torque profile at the ankle joint approximated that of the biological torque during normal walking. Seven participants walked on a treadmill at 1.5 meters per second under one unpowered and four powered conditions, where the peak moment applied at the ankle joint was varied from about 10 to 38% of biological ankle moment (equivalent to an applied force of 18.7 to 75.0% of body weight). Results showed that, with increasing exosuit assistance, net metabolic rate continually decreased within the tested range. When maximum assistance was applied, the metabolic rate of walking was reduced by 22.83 ± 3.17% relative to the powered-off condition (mean ± SEM).
在为任何用于步行辅助的可穿戴机器人定义需求时，重要的是要在最大限度地提高用户因外骨骼辅助而获得的代谢益处的同时，将携带系统质量的代谢负担限制在最低水平。因此，本研究的目的是分离并描述辅助幅度与穿着者行走代谢成本之间的关系，同时还研究了穿着者潜在步态力学的变化。该研究在正常行走过程中使用 tethered 多关节软外骨骼进行，由于纺织结构，辅助力直接作用于踝关节，间接作用于髋关节。外骨骼控制器的设计使得在踝关节处施加的扭矩曲线与正常行走时的生物扭矩近似。七名参与者在跑步机上以每秒 1.5 米的速度行走，在一种无动力和四种动力条件下，踝关节处施加的峰值力矩从大约 10%到 38%的生物踝关节力矩变化（相当于施加的力从体重的 18.7%到 75.0%）。结果表明，随着外骨骼辅助的增加，在测试范围内，净代谢率持续下降。当施加最大辅助力时，与关闭电源状态相比，行走的代谢率降低了 22.83 ± 3.17%（平均值 ± SEM）。
