Hand tool handle size and shape determination based on hand measurements using a contour gauge

The purpose of this study is to provide a novel approach to tool handle design and development based on measurements of hand shape using a contour gauge. In general, traditional design techniques, designing based on anthropometric data, and derived mathematical models do not incorporate enough subject data to design a customized product. First, anthropometric measurements on the right hand of 60 participants were collected with a contour gauge to manufacture matching handles. A curved handle fitting the human hand was constructed with common computer‐aided design software, and cylindrical handles and elliptical handles were added for comparison. All of the handles were used to record the participants' grip force to evaluate the operating efficiency of the handles. Finally, the participants completed a comfort‐rating questionnaire. The results show that contours based on the hand provided the highest operating performance and the best overall comfort‐rating compared to cylindrical handles and elliptical cylindrical handles. The newly developed handles in the grip force tasks have the highest push performance and the best comfort ratings compared to traditional cylindrical and elliptical handles. The developed handles could provide the hand tool industry information on developing and manufacturing many other similar handle designs (such as those for saws and electric screwdrivers).