Fang Shanpu, Shepard Riley J, Bowersock Collin D, Lerner Zachary F
Department of Mechanical Engineering, Northern Arizona University, Flagstaff, AZ 86001 USA.
Department of Mechanical Engineering, Northern Arizona University, Flagstaff, AZ 86001 USA, and also with the College of Medicine-Phoenix, University of Arizona, Phoenix, AZ 85004 USA.
IEEE Trans Med Robot Bionics. 2025 May;7(2):699-710. doi: 10.1109/tmrb.2025.3550661. Epub 2025 Mar 19.
Motor-powered ankle exoskeletons have been shown to improve walking and rehabilitation outcomes in individuals with and without gait impairments (e.g., cerebral palsy (CP)). To date, ankle exoskeleton designs have either placed the motors on the shanks (direct or quasi-direct drive) or around the waist with Bowden cable transmissions. The former offers better transmission efficiency, while the latter reduces added mass biomechanical penalty. The biomechanical effects of motor placement may be magnified for individuals with CP due to weakened lower limb strength. To date, no study has compared how motor placement alters the biomechanical responses and user perceptions of individuals with or without gait impairment (e.g., CP). In this study involving 7 individuals with CP and 9 unimpaired individuals, we compared their metabolic cost of transport, lower limb muscle activities, and user perceptions when using ankle exoskeletons with either waist-mounted motors (and Bowden cables) or shank-mounted motors that were otherwise identical. Despite changes in lower leg muscle recruitment, results showed no statistical differences in the metabolic cost of transport. Shank-mounted motors were preferred by more participants in both cohorts (e.g., 6/7 in CP). These results help inform the ergonomics and mechanical designs of ankle exoskeletons and how they may be perceived.
已证明电动脚踝外骨骼可改善有或没有步态障碍（如脑瘫（CP））的个体的行走和康复效果。迄今为止，脚踝外骨骼设计要么将电机置于小腿上（直接或准直接驱动），要么通过鲍登电缆传动装置置于腰部周围。前者具有更高的传动效率，而后者则减少了附加质量的生物力学负担。由于下肢力量减弱，电机放置的生物力学效应对于患有脑瘫的个体可能会被放大。迄今为止，尚无研究比较电机放置如何改变有或没有步态障碍（如脑瘫）的个体的生物力学反应和用户感受。在这项涉及7名脑瘫个体和9名无损伤个体的研究中，我们比较了他们在使用腰部安装电机（和鲍登电缆）或小腿安装电机的脚踝外骨骼时的运输代谢成本、下肢肌肉活动和用户感受，两种外骨骼在其他方面相同。尽管小腿肌肉募集情况有所变化，但结果显示运输代谢成本没有统计学差异。在两个队列中，更多参与者更喜欢小腿安装电机（如在脑瘫队列中为6/7）。这些结果有助于为脚踝外骨骼的人体工程学和机械设计以及它们可能被感知的方式提供信息。
