Usability of finite elements based on the absolute nodal coordinate formulation for deformation analysis of the Achilles tendon

This work explores the modelling of soft tissues, particularly the Achilles tendon, using the absolute nodal coordinate formulation (ANCF).The anisotropic Gasser–Ogden–Holzapfel (GOH) potential energy function provided the necessary anisotropic elastic feature descriptions. A generalized one-dimensional Maxwell model described the viscoelastic effects. Finally, a parameter-based damage model characterized the effects of repetitive loading. We used an objectivity test to establish multibody system dynamics usability. The test ascertains whether or not the developed elements can adequately describe rigid body motion and therefore be applied to describe large deformation in whole bodies. Comparing our results against high-fidelity ANSYS 3D FEA solutions served as verification. To further ensure the validity of the obtained solutions, our results were also compared against test results. For modelling material behaviour, the developed ANCF elements demonstrated substantial fidelity, and simulation results agreed well with test results and results found in the literature.