Hand Surface Area Variation Analyzed by 3D Laser Scan Measurement

• Main Authors: Lin,Po-Tsun, 林柏村
• Other Authors: Lin, Ching-hua
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/99189083834867109100

碩士 === 中華大學 === 工業管理學系碩士班 === 103 === Gloves are designed and used to protect our hands from various impairment and hurt. However, the lack of comfort and the reduction of dexterity of hands often frustrate the use of gloves. Thus, a good design of gloves has to provide both fitness and movability for hands. For fitness, traditionally hand dimensions had been measured by tapes, calipers and Martin-type anthropolometers to develop glove size models. Or nowadays the surface shape of hands had been measured by 3D laser scanning technologies under some standard posture to estimate the shape and area of gloves. Both approaches failed to estimate the variation of hand surface area (HSA) as hands moving from one posture to another. Thus, suggestions for the design of glove movability are scarce, except to use flexible materials on joint area of gloves.This study aimed to analyze HSA variation among different postures using 3D laser scan measurement. The raw 3D surface shape of hands was measured by a laser scan system with resolution of 1mm×1mm×1mm and precision of ± 0.4mm. The consequent data of a digital hand comprised about forty thousand 3D coordinates, which afterwards had been transformed into triangular meshes, and HSA was calculated by the summation of all tiny triangular area of the mesh data. Each hand was measured under six different postures, three standard and three functional, including fingers stretched and palm expanded, fingers stretched and all close, fingers stretched and only thumb open, relaxed, grasped, and fisted. The areas of palm and fingers were calculated separately. The area of palm of fingers stretched and all close was calculated as a base, and the variation of the other five postures from it was analyzed. The area of fingers was calculated in one standard posture and the variation of the three functional postures from it was analyzed. Resulted mean area variation percentage of palm and five fingers of hand were tabulated to propose guidelines for the extent of flexibility of gloves.