Gait modification for improving walking stability of exoskeleton assisted paraplegic patient
Gait modification for improving walking stability of exoskeleton assisted paraplegic patient
复制标题
DOI：
10.1186/s40648-020-00169-y
复制
发表时间：
2020-04-30
期刊：
影响因子：
1.4
通讯作者：
Hasegawa, Yasuhisa
中科院分区：
文献类型：
--
作者：
Li, Mengze;Aoyama, Tadayoshi;Hasegawa, Yasuhisa
用于辅助截瘫患者行走的当前可用的外骨骼通常适应涉及患者跟随外骨骼引线的预编程步态。该系统允许患者握住一对手杖以保持平衡，并且在没有患者动作的情况下无助于保持平衡。提出了一种基于零力矩点（ZMP）的截瘫患者扶拐外骨骼步行步态修正算法。拟议的ZMP将使截瘫患者在行走时保持平衡，并减轻维持平衡的负担。首先，一对手杖被用作接口来控制用户的行走，然后，腿和手杖之间的协同作用被用于在外骨骼运动期间同步用户的行走意图。步行协同提取健全的主体步行与一对手杖，并使用主成分分析（PCA）进行分析。为提高步行稳定性，基于ZMP算法对步行过程中站立腿髋关节角度进行修正。此外，一个非线性倒立摆（NIP）模型，以产生一个完全伸展的膝关节角度，这是类似于人类步态的步态。所提出的方法进行了验证，通过凉亭模拟使用步行机器人来模拟病人穿着外骨骼。实验结果表明，步态修正后的步行稳定性得到了很大的提高。
The currently available exoskeleton for assisting the paraplegic patient in walking usually adapts a pre-programmed gait that involves the patient following an exoskeleton lead. The system allows the patient to hold a pair of canes in order to keep balance, and does not contribute to keeping balance without the patient's action. This paper proposes an algorithm based on the zero moment point (ZMP) to modify the gait generated through human walking synergy for paraplegic patients who make use of the exoskeleton system and hold their canes. The proposed ZMP will enable the paraplegic patient to keep balance during walking and also reduce the burden in maintaining balance. First, a pair of cane is used as an interface to control the user's walking and then, the synergy between legs and canes is used to synchronize the user's walking intention during the exoskeleton movement. The walking synergy is extracted from the able-bodied subject walking with a pair of canes and analyzed using principal component analysis (PCA). In order to improve the walking stability, the hip joint angle on stance leg during walking was modified based on ZMP. Furthermore, a nonlinear inverted pendulum (NIP) model was utilized in order to generate a gait with a fully stretched knee joint angle that is similar to human gait. The proposed method was verified via the Gazebo simulation using a walking robot to simulate a patient wearing an exoskeleton. The experiment results show that the walking stability was highly improved after gait modification.