From: Geometric conditions of a two-link-and-six muscle structure based on internal force stability

Symbol | Meaning |
---|---|

\(\tilde{i} = 5,6\) | The number of the biarticular muscle |

\({\varvec{l}}_{\tilde{i}}\), \({\varvec{r}}_{\tilde{i}}\) | The vectors from the rotational center of each joint to the muscular fixed points |

\(l_{\tilde{i}}\), \(r_{\tilde{i}}\) | The lengths of the vector \({\varvec{l}}_{\tilde{i}}\) and \({\varvec{r}}_{\tilde{i}}\) |

\(\phi _{\tilde{i}}\) | The angle between the base and the vector \({\varvec{l}}_{\tilde{i}}\) |

\(\psi _{\tilde{i}}\) | The angle between the base and the vector \({\varvec{r}}_{\tilde{i}}\) |

\(\theta _{\phi \tilde{i}}\) | The angle between \({\varvec{l}}_{\tilde{i}}\) and the 1st link |

\(\theta _{\psi \tilde{i}}\) | The angle between \({\varvec{r}}_{\tilde{i}}\) and the 1st link |