「抓握」是人類行為中最常見且最普遍的動作，手指與物體的接觸摩擦更是影響抓握效果的要因；抓握動作亦常受到環境中水的影響，而人類無毛的手指及腳趾，泡在水中一段時間後會起皺，起皺原因的推論有表皮層吸水或是神經導致血管收縮等因素。此起皺現象會影響到手指的抓握行為。而手指浸泡在水中會起皺，影響抓握的效果；最常見的範例如：廚房洗菜後需要抓握菜刀柄、鍋鏟等廚房用具，或是在泳池游泳後，起身所需要抓握欄杆等動作。因此，手指泡水起皺如何影響抓握動作的研究對於安全性是充分且必要的。
皮膚磨潤學的研究能有效模擬生活環境中人體皮膚與接觸表面的接觸。在日常生活中常因為環境的因素使手指泡水而起皺。為了研究手指起皺對抓握表現的影響，本研究中透過墨水法以及高速攝影機來量測手指接觸面積、並透過Corneometer®測量手指皮膚含水量、使用專為軟材料開發的多功能軟組織摩擦磨損試驗機(UMT-2)來進行摩擦試驗以及高速攝影機拍攝手指滑動結果來證明排水效果的有無，最後設計抓握實驗來驗證摩擦實驗的結果。實驗結果彼此間互相關聯，藉此定義手指起皺前後對「抓握」效果的影響。

The act of gripping an object is one of the most common actions in our daily lives. Grip performance relies on the contact friction of fingers. It is also affected by water environments; some of the most common examples include: washing vegetables and dishes, handling kitchen utensils while cooking, grasping the railing after swimming in the pool, and so on. The hairless human fingers and toes will become wrinkled after soaking in water for a period of time. There may be two reasons why fingers wrinkle: One is the absorbency of the finger’s epidermis, and the other is that stimulated skin nerves cause vasoconstriction. This wrinkled phenomenon affects the performance of finger grip and has an influence on the safety and convenience of everyday life. So, it is important and necessary to know how water-induced wrinkled finger impacts grip performance.

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