Figure 7.

Gaussian distributed noise added to the recorded stretch experimental data (discrete markers) in the fiber (a) and cross fiber (b) directions. Three different ratios between fiber stretch λ₁ and cross fiber stretch λ₂ are considered, i.e., 1:1 (λ₁ = λ₂, circular markers ○), 2:1 (λ₁ = 2λ₂, square markers □), and 1:2 (λ₂ = 2λ₁, triangular markers ▽). On each side of the experimentally measured curves in panels (a) and (b), the 97.5% percentile limit corresponding to 10%, 20%, and 30% is reported (shaded regions on each side of the experimental markers). The confidence ellipses corresponding to the three levels of noise (±10%, ±20%, and ±30%) are reported in panel (c). The confidence ellipses are normalized with respect to the material properties α̂₁ and α̂₂ identified without noise.