An Examination of the Speed of Manipulation of Various Sizes and Shapes of Handles
David J. Cochran, Michael W. Riley · Proceedings of the Human Factors and Ergonomics Society Annual Meeting · 1983
This research examined the effects of handle size and shape on two types of manual manipulation of handles. The first task evaluated was one in which the subject rotated a handle 180° in his/her hand one way, then reversed the rotation for 180° in the opposite direction. On this task smaller handles could be manipulated faster. Also triangular handles were significantly slower to manipulate than all other shapes tested except the square ones. The second task evaluated the speed of flipping a handle in the hand. For this task shape had no significant effect on the time but size did. Once again, the smaller handles could be manipulated quicker than the larger ones.