1999 Volume 45 Issue 5 Pages 69-76
For the columnar apparatus assuming a knob, handle and cap, the state of rotary control was studied using the columnar apparatus for 23 men and 9 women, their age were 19-20 years old. The method of experiment was as follows. Wooden 45 columned objects with different diameter (height 5Omm) were prepared. Diameter of these objects were 7-130mm, randomly chosen. The objects were set in the holder on the table, and then were turned to clockwise with the right hand. The condition of operating was recorded by a video camera from the bottom, and the relationships of contacting position between objects and each fingers were obtained from video recording. As a result, we could understand the boundaries of the number of fingers which were relatively shown, used at the time of starting of rotary control. And expanding the diameter of column, the touching points of fingers were approximated by the quadratic curves and clarified how they change. This result is available for designing the shape of the columnar apparatus for rotary control.