Aiming at the problem of how to store/release gait energy with high efficiency for the conventional unpowered lower extremity exoskeletons, an unpowered lower-limb exoskeleton is proposed. In the current study, the human motion model is established, and the change rule and recovery/utilization mechanism of gait energy are illustrated. The stiffness and metabolic cost of relevant muscles in lower extremity joints are obtained based on OpenSim software. The results show that stiffness of muscle is increased when muscle concentric contraction generates positive work, but it is reverse when muscle eccentric contraction generates negative work. Besides, metabolic cost of the soleus, gastrocnemius, and tibialis anterior decreased about 31.5%, 34.7%, and 40%, respectively. Metabolic cost of the rectus femoris, tensor fascia lata, and sartorius decreased about 36.3%, 7%, and 5%, respectively, and the total metabolic cost of body decreased about 15.5%, under the exoskeleton conditions. The results of this study can provide a theoretical basis for the optimal design of unpowered lower extremity exoskeleton.

中文翻译：

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基于步态能量的无动力下肢外骨骼建模与仿真

针对常规无动力下肢外骨骼如何高效地存储/释放步态能量的问题，提出了一种无动力下肢外骨骼。在本研究中，建立了人体运动模型，并阐明了步态能量的变化规律和恢复/利用机制。下肢关节相关肌肉的刚度和代谢成本基于OpenSim软件获得。结果表明，当肌肉同心收缩产生正功时，肌肉的刚度增加，而当肌肉偏心收缩产生负功时则相反。此外，比目鱼肌，腓肠肌和胫骨前肌的代谢成本分别降低了约31.5％，34.7％和40％。股直肌，张量筋膜的代谢成本 在外骨骼条件下，阿司匹林和赛多利斯的肌肉分别降低了约36.3％，7％和5％，人体的总代谢成本降低了约15.5％。研究结果可为无动力下肢外骨骼的优化设计提供理论依据。