Figure 3.

(a) Deformation of a unit cube when activated in the fiber direction; analytical results along the fiber, sheet, and sheet-normal directions using different values for the distribution parameters κ_f in (b) and κ_s in (c). The fiber, sheet, and sheet-normal responses are shown by solid, dashed, and dotted curves, respectively, and the circles show the finite element results for comparison reasons using either κ_f = 1/6, see (b), or κ_s = 1/6, see (c). Using the limiting case κ_f = 1/3 or κ_s = 1/3, the dash-dotted curves show the stretch responses for all three f, s, and n-directions, see (b), and for the s and n-directions, see (c).