Fig. 1. Schematic of the force balance for the drag measurements. The crab was supported at a distance l₁ below the pivot point. A weight (W) on the horizontal lever arm, at a distance l₂ from the pivot point, provided a moment in the opposite sense to that of the drag force (F_D). F_shaft represents the drag force on the submerged section of the support shaft, which is at a distance l_shaft below the pivot point.