Table 5 Geometric conditional angles \(\beta _i\) and \(\gamma _i\) for each muscular arrangement
From: Geometric conditions of a two-link-and-six muscle structure based on internal force stability
| Â | Simple-joint muscles | Biarticular muscles |
|---|---|---|
A | ||
   Conditions [deg] | \(\beta _{1...4}>90\) or \(\gamma _{1...4}>90\) | \(\beta _{5, 6}>90\) and \(\gamma _{5, 6}>90\) |
   \(\beta _{1...6}\) [deg] | 95.1, 95.1, 95.1, 95.1 | 120.0, 120.0 |
   \(\gamma _{1...6}\) [deg] | 29.9, 29.9, 29.9, 29.9 | 120.0, 120.0 |
B | ||
   Conditions [deg] | \(\beta _{1...4}>90\) or \(\gamma _{1...4}>90\) | \(\beta _{5, 6}>90\) and \(\gamma _{5, 6}>90\) |
   \(\beta _{1...6}\) [deg] | 67.5, 67.5, 67.5, 67.5 | 90.0, 90.0 |
   \(\gamma _{1...6}\) [deg] | 27.5, 27.5, 27.5, 27.5 | 90.0, 90.0 |
C | ||
   Conditions [deg] | \(\beta _{1...4}>90\) or \(\gamma _{1...4}>90\) | \(\beta _{5, 6}>90\) and \(\gamma _{5, 6}>90\) |
   \(\beta _{1...6}\) [deg] | 95.1, 95.1, 95.1, 95.1 | 90.0, 90.0 |
   \(\gamma _{1...6}\) [deg] | 29.9, 29.9, 29.9, 29.9 | 90.0, 90.0 |
D | ||
   Conditions [deg] | \(\beta _{1...4}>90\) or \(\gamma _{1...4}>90\) | \(\beta _{5, 6}>90\) and \(\gamma _{5, 6}>90\) |
   \(\beta _{1...6}\) [deg] | 67.5, 67.5, 67.5, 67.5 | 120.0, 120.0 |
   \(\gamma _{1...6}\) [deg] | 27.5, 27.5, 27.5, 27.5 | 120.0, 120.0 |