Abstract
The purpose of this thesis is to study the relationship between static hand dimensions and functional hand dimensions in grasping by means of the methods of anthropometry and to compare the variations of these two dimensions to make prediction models of hand dimensions. This study consists of two experiments. The first part is preliminary tests. In the first experiment there are 4 male and 4 female subjects, representing different hand length groups. Using the direct-measure method, subjective comfortability scale and 6 different handle diameters (25, 30, 35, 40, 45 and 50 mm) to find out the relationship among handle diameters, hand dimensions and subjective comfortability of subjects. There are 15 male and 15 female subjects in the second experiment and each subject is asked to paste with marks on the defined points on the hand. Each hand dimension is measured by means of the direct-measure method and 3D-scan method. According to the results of the first experiment, each subject is given a fit handle covered with 10 mm clay to grasp. After grasping, the handles will be scanned by the 3D scanner. After the experiments, these conclusions are made.1. By the results, the 17 points defined in this study can be the key points between static hand dimensions and functional hand dimensions.2. When grasping the handles with comfort and without force, there are 12 constant ratios of variations between static hand dimensions and functional hand dimensions in grasping. For example, the constant ratio for index finger is 0.3623; for middle finger is 0.4016; for ring finger is 0.3632; for little finger is 0.3253. 3. Although one’s hand dimensions are different from another, the ratios between static hand dimensions and functional hand dimensions in grasping with comfort and without force are constant. Excluding the other factors such as force or angles of joints, this thesis only includes with factors, subjective comfortability, handle diameters and hand dimensions. This is the limitation of this thesis.