Figure 2
From: Evidence to support the mechanical advantage hypothesis of grasping at low force levels

Schematic diagram of the experimental setup. The figure shows the experimental setup with a participant holding the experimental handle in front of the computer monitor. The monitor displayed a solid horizontal line that corresponded to the target normal force to be produced by the thumb. During high force level grasp condition, the solid horizontal line shown on the monitor corresponded to 14 N of normal force to be produced by the thumb. Whereas during low force level grasp condition, the solid horizontal line shown on the monitor corresponded to 7 N of normal force to be produced by the thumb. The two dashed lines above and below the solid line signify an error margin of ± 0.5 N.