Figure 5.

Normal force in a quadrant observed during torque exertion on elliptic cylinder handles significantly varied for the interaction between handle size and quadrant (a) and for the interaction between torque direction and quadrant (b). Normal force in each quadrant was, on average, 12% greater for the aluminum- than rubber-finished elliptic cylinders (c). The quadrant forces on elliptic cylinder handles were, in general, higher than the average quadrant force on circular cylinder handles (total normal force divided by 4) denoted by the segmented line in b. Only elliptic cylinder handle data are shown. For each figure, all other conditions not specified were pooled.