Table 1.
Element type, mesh count, and material property of the model components.
| Model component | Element type | Material property | Density | Poisson's ratio | Mesh count |
|---|---|---|---|---|---|
| Skin | Linear triangular shell (S3R) | Hyper-elastic (first-order Ogden model, μ = 0.122 MPa, α = 18) Thickness: 2.0 mm |
950 kg/m3 | N/A | 3062 |
| Bulk soft tissue | SPH particle (PC3D) | Linearly elastic (Young's modulus: 0.83 MPa for the plantar heel, 0.70 MPa for the plantar forefoot/toe, 0.67 MPa for the plantar midfoot, and 0.20 MPa for the rest) | 950 kg/m3 | 0.4 | 124778 |
| Periosteum | Linear triangular shell (S3R) | Linearly elastic (Young's modulus: 0.9 MPa) Thickness: 1.5 mm |
1000 kg/m3 | 0.4 | 19979 |
| Bone | Linear tetrahedral solid (C3D4) | Linearly elastic (Young's modulus: 17000 MPa) | 1990 kg/m3 | 0.3 | 18965 |
| Extrinsic foot muscles | Slip ring connector | Linearly elastic (stiffness: 157.4 N/mm) | 1000 kg/m3 | N/A | N/A |
| Intrinsic foot muscles | Two-node truss (T3D2) | Linearly elastic (Young's modulus: 264.8 MPa) Cross-section area: 10 mm2 |
1000 kg/m3 | 0.4 | 24 |
| Rearfoot ligaments | Two-node truss (T3D2) | Linearly elastic (Young's modulus: 100–320 MPa) Cross-section area: 7.1–256 mm2 |
1000 kg/m3 | 0.4 | 20 |
| Other ligaments | Two-node truss (T3D2) | Linearly elastic (Young's modulus: 264.8 MPa) Cross-section area: 10 mm2 |
1000 kg/m3 | 0.4 | 67 |
| Ground plate | Linear tetrahedral solid (C3D4) | Linearly elastic (Young's modulus: 17000 MPa) | 1000 kg/m3 | 0.3 | 2850 |
| Plantar fascia | Slip ring connector | Linearly elastic (stiffness: 182.4–232.5 N/mm) | 1000 kg/m3 | N/A | N/A |
| TAA metal components | Linear quadrilateral shell (S4R) | Linearly elastic (cobalt chromnium: 210000 MPa) | 10000 kg/m3 | 0.29 | 18239 |
| TAA bearing component | Linear quadrilateral shell (S4R) | Linearly elastic (polyethylene: 475 MPa) | 900 kg/m3 | 0.38 | 5982 |
| TTR talus prosthesis | Linear tetrahedral solid (C3D4) | Linearly elastic (cobalt chromnium: stiffness: 210000 MPa) | 10000 kg/m3 | 0.29 | 8453 |