本研究透過力學分析，設計一款具有緩衝與儲能特性之鞋底彈性結構，可減緩穿戴者下肢活動時的不適感，並提供足夠的回彈能量協助下肢推蹬，減輕下肢肌力之負擔。
本研究所設計之鞋底彈性結構，具有非線性剛性的特質，在結構受壓的前期，較小的剛性可以消除衝擊力；而受壓中期的線性剛性，使彈性結構可儲存更多的能量做為回彈助力；受壓後期非線性增加的剛性，則可以消除原有普通鞋觸底時的不適感。
本研究引入步態分析與人體數學模型後，以此訂立彈性結構之性能目標。研究中以電腦輔助設計與有限元素法驗證理論結果，再將波型彈簧的各項幾何參數與彈簧性能的關係列出，並說明其設計方法。最後以合乎實例之條件設計波型彈簧，得到具備緩衝能力(初始剛性114.4 N/mm)，與可儲存約81 %之步行落差位能(現有之波型彈簧鞋Spira僅約7.4 %)，與54 %之跑步落差位能之設計。

Base on mechanical analysis, this study designs an elastic structure with cushioning and energy storage ability, which can relieve the discomfort during lower limb activities, and provide rebounding energy to assist the user at the same time.
The elastic structure of the footwear designed in this research has the characteristics of Nonlinear rigidity. In the early stage of the compression of the structure, the smaller rigidity can eliminate the impact force; the linear rigidity in the middle stage of compression enables to store more energy; the Non-linear rigidity in the later stage of compression can eliminate the discomfort when the sole is fully compressed.
This study uses gait analysis and a mathematical model of the human body to define the geometric and performance goals of elastic structures. The performance differences of the coil spring and the wave spring are theoretically discussed, and supported by computer-aided design and the finite element method results. Also, the relationship between the geometric of the wave spring and the performance is listed. Finally, an example is designed by a realistic conditions with cushioning ability (initial rigidity is about 114 N/mm), which can store about 81% of the walking potential energy (the wave spring shoe Spira is only about 7.4%) and 54% of the running potential energy.

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