國內研究顯示，造成輕微頭部外傷的兩大主因是車禍及跌落，若將調查的對象針對0至14歲的兒童可以發現，車禍中以機車為大宗；跌落則是以低處跌落為多。為了探討人體跌落的行為模式，使用汽車安全中常用的碰撞人偶作為研究基礎，碰撞人偶已發展30年以上，符合許多人體的生物真實性，如頭部、頸部、胸部等位置在撞擊後動態特性，因此可以代替人體進行測試。

本研究即是利用碰撞人偶的特性，使用實驗及電腦模擬的方式，對人體跌落的行為做一番探討。因為人體在跌落時的動作及條件不易確定，將人體簡化為三大區塊，頭、頸及軀幹，再根據兒童人偶尺寸、重量及台灣人體計測資料庫分別建立實驗用的人偶及電腦模型，研究中分別將人偶吊起並且以不同的高度及角度做跌落測試，表示在人體跌落時不同的高度及姿勢，之後整理頭部傷害指數對實驗及模擬做比較。

本論文對人體跌落行為進行初步的分析及討論，從實驗及模擬的結果來看，都可以發現到當有軀幹的加入後得到的頭部傷害較小，其原因是頸部的壓縮及變形吸收了跌落時的能量，加上軀幹的延遲落下使頭部反彈受到限制。 在模擬中得到的頭部加速度及傷害均比實驗結果來的大，但兩者之間差異性都在一定範圍中，因此可對模擬結果修正來預測實驗。 同時在電腦模擬中改變了頸部的強度及撞擊橡膠墊的厚度，發現到當頸部較硬或是橡膠墊愈厚時得到的頭部傷害較小。

According to the studies, two major causes for mild head injury in Taiwan were falls and traffic accidents. Especially for falling within short distance and motorcycle accidents, children usually are main victims. Therefore, there is of interest to analyze child biomechanical behavior due to falling, which might develop head injury. By studying the falling behavior, the protection strategy could be resulted. Crash dummies with good biofidelity were used over 30 years to improve the safety of vehicle. In this study, the child crash dummy was chosen as an experimental device to analyze the kinetics of falling tests. In addition, simulations based on the tested were conducted as well.

The current dummy, Hybrid III, is based on 50th percentile male and the child dummy normally is based on the scaled data since lack of biomechanical data from children. The main focus in this study is child; therefore, the scaled method was discussed as well. Furthermore, due to the complication and uncertainty by using full dummy, the test device in this study was redesigned into 3 major segments. They are head, neck, and one rigid body, which major injuries usually occur during falling impact. Both experiments and simulations were based on this simplified dummy. Tests were conducted by hanging the dummy and dropping from different height and angle, then impacting to different environments, metal and rubber plane.

Compared the results of experiment and simulation, simulation got more severity head injury than experiment. That showed there were some different between experiment and simulation but the ratio between them was consistent. When the rigid body and neck was involved in the experiment or simulation, the head injury criterion (HIC) was smaller than the test only by dummy head according to the results. The main reason probably is because part of impacting energies was absorbed by the compression and deformation of neck. Rubber plane was useful to protect head. As the thickness of rubber was larger, the HIC was smaller according to our studies. However, it wasn’t linear. Finally, the design strategy for improving the safety of child from falling was suggested.

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