HAND TOOL INTERFACE EFFECTS ON HUMAN TORQUE CAPACITY/

Forty student subjects, involving 20 males and 20 females, participate d in this study. Four handle shapes (circular, triangular, square and hexagonal), seven handle sizes, (25.4, 31.8, 38.1, 44.5, 50.8, 57.2 an d 63.5 mm)), and five types of gloves (surgical, single cotton, double cottons, leather and rubber) were rested for their effects on maximum volitional torque exertion (MVTE) for supination. The results indicat ed that all the main effects were significant (p < 0.001). Female MVTE is about 62% of male. Triangular shape was the most favorable, follow ed by square, hexagonal and circular shapes despite of the moment arms being in the ratios of 1.155, 1.414, 1 and 1. The gloved MVTEs are ge nerally found to be superior to without gloves, about 10% to 30% incre ment. A positive correlation between supination MVTE and glove thickne ss is also found. For handle size effect, the larger the handle size i s, the greater the MVTE is. Female has more effective torque exertion than that of male for handle size less than 44.5 mm (1.75 '').