Ramanujam Arvind, Momeni Kamyar, Ravi Manikandan, Augustine Jonathan, Garbarini Erica, Barrance Peter, Spungen Ann M, Asselin Pierre, Knezevic Steven, Forrest Gail F
Kessler Foundation, West Orange, NJ, United States.
Koneksa Health, New York, NY, United States.
Front Robot AI. 2020 Dec 9;7:574365. doi: 10.3389/frobt.2020.574365. eCollection 2020.
Gait analysis studies during robot-assisted walking have been predominantly focused on lower limb biomechanics. During robot-assisted walking, the users' interaction with the robot and their adaptations translate into altered gait mechanics. Hence, robust and objective metrics for quantifying walking performance during robot-assisted gait are especially relevant as it relates to dynamic stability. In this study, we assessed bi-planar dynamic stability margins for healthy adults during robot-assisted walking using EksoGT™, ReWalk™, and Indego® compared to independent overground walking at slow, self-selected, and fast speeds. Further, we examined the use of forearm crutches and its influence on dynamic gait stability margins. Kinematic data were collected at 60 Hz under several walking conditions with and without the robotic exoskeleton for six healthy controls. Outcome measures included (i) whole-body center of mass (CoM) and extrapolated CoM (X), (ii) base of support (BoS), (iii) margin of stability (MoS) with respect to both feet and bilateral crutches. Stability outcomes during exoskeleton-assisted walking at self-selected, comfortable walking speeds were significantly ( < 0.05) different compared to overground walking at self-selected speeds. Unlike overground walking, the control mechanisms for stability using these exoskeletons were not related to walking speed. MoSs were lower during the single support phase of gait, especially in the medial-lateral direction for all devices. MoSs relative to feet were significantly ( < 0.05) lower than those relative to crutches. The spatial location of crutches during exoskeleton-assisted walking pushed the whole-body CoM, during single support, beyond the lateral boundary of the lead foot, increasing the risk for falls if crutch slippage were to occur. Careful consideration of crutch placement is critical to ensuring that the margins of stability are always within the limits of the BoS to control stability and decrease fall risk.
机器人辅助行走过程中的步态分析研究主要集中在下肢生物力学方面。在机器人辅助行走期间，用户与机器人的交互及其适应性会转化为改变的步态力学。因此，用于量化机器人辅助步态期间行走性能的稳健且客观的指标与动态稳定性密切相关。在本研究中，我们使用EksoGT™、ReWalk™和Indego®评估了健康成年人在机器人辅助行走期间的双平面动态稳定性裕度，并将其与在慢速、自选速度和快速下的独立地面行走进行比较。此外，我们研究了前臂拐杖的使用及其对动态步态稳定性裕度的影响。在有和没有机器人外骨骼的几种行走条件下，以60Hz的频率为六名健康对照者收集运动学数据。结果测量包括：(i) 全身质心（CoM）和外推质心（X），(ii) 支撑面（BoS），(iii) 相对于双脚和双侧拐杖的稳定性裕度（MoS）。与自选速度下的地面行走相比，外骨骼辅助行走在自选舒适行走速度下的稳定性结果有显著差异（<0.05）。与地面行走不同，使用这些外骨骼进行稳定性控制的机制与行走速度无关。在步态的单支撑阶段，MoS较低，尤其是在所有设备的内外侧方向。相对于双脚的MoS显著低于相对于拐杖的MoS（<0.05）。外骨骼辅助行走期间拐杖的空间位置在单支撑时将全身CoM推到前脚的外侧边界之外，如果拐杖滑倒则会增加跌倒风险。仔细考虑拐杖放置对于确保稳定性裕度始终在支撑面范围内以控制稳定性并降低跌倒风险至关重要。
