This information is part of the Modelica Standard Library maintained by the Modelica Association.

# UniversalSpherical

Universal - spherical joint aggregation (1 constraint, no potential states)

CONNECTORS

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Name | Type | Description | |
---|---|---|---|

frame_a | Frame_a | Coordinate system fixed to the component with one cut-force and cut-torque | |

frame_b | Frame_b | Coordinate system fixed to the component with one cut-force and cut-torque | |

frame_ia | Frame_a | Coordinate system at the origin of frame_a, fixed at the rod connecting the universal with the spherical joint |

PARAMETERS

Name | Type | Default Value | Description |
---|---|---|---|

animation | Boolean | true | = true, if animation shall be enabled |

showUniversalAxes | Boolean | true | = true, if universal joint shall be visualized with two cylinders, otherwise with a sphere (provided animation=true) |

computeRodLength | Boolean | false | = true, if distance between frame_a and frame_b shall be computed during initialization (see info) |

n1_a | Axis | {0,0,1} | Axis 1 of universal joint resolved in frame_a (axis 2 is orthogonal to axis 1 and to rod) |

rRod_ia | Position[3] | {1,0,0} | Vector from origin of frame_a to origin of frame_b, resolved in frame_ia (if computeRodLength=true, rRod_ia is only an axis vector along the connecting rod) |

sphereDiameter | Diameter | world.defaultJointLength | Diameter of spheres representing the universal and the spherical joint |

rodShapeType | ShapeType | "cylinder" | Shape type of rod connecting the universal and the spherical joint |

rodWidth | Distance | sphereDiameter/Types.Defaults.JointRodDiameterFraction | Width of rod shape in direction of axis 2 of universal joint. |

rodHeight | Distance | rodWidth | Height of rod shape in direction that is orthogonal to rod and to axis 2 |

rodExtra | ShapeExtra | 0.0 | Additional parameter depending on rodShapeType |

cylinderLength | Distance | world.defaultJointLength | Length of cylinders representing the two universal joint axes |

cylinderDiameter | Distance | world.defaultJointWidth | Diameter of cylinders representing the two universal joint axes |

kinematicConstraint | Boolean | true | = false, if no constraint shall be defined, due to analytically solving a kinematic loop |

checkTotalPower | Boolean | false | = true, if total power flowing into this component shall be determined (must be zero) |

rodLength | Distance | Modelica.Math.Vectors.length(rRod_ia) | Length of rod (distance between origin of frame_a and origin of frame_b) |

eRod_ia | Real[3] | Modelica.Math.Vectors.normalize(rRod_ia) | Unit vector from origin of frame_a to origin of frame_b, resolved in frame_ia |

e2_ia | Real[3] | Modelica.Math.Vectors.normalize(cross(n1_a, eRod_ia)) | Unit vector in direction of axis 2 of universal joint, resolved in frame_ia (orthogonal to n1_a and eRod_ia; note: frame_ia is parallel to frame_a when the universal joint angles are zero) |

e3_ia | Real[3] | cross(eRod_ia, e2_ia) | Unit vector perpendicular to eRod_ia and e2_ia, resolved in frame_ia |

USED IN EXAMPLES

Modelica.Mechanics.MultiBody.Examples.Loops.Fourbar2 One kinematic loop with four bars (with UniversalSpherical joint; 1 non-linear equation) |

USED IN COMPONENTS

Modelica.Mechanics.MultiBody.Joints.Assemblies.JointUSR Universal - spherical - revolute joint aggregation (no constraints, no potential states) | |

Modelica.Mechanics.MultiBody.Joints.Assemblies.JointUSP Universal - spherical - prismatic joint aggregation (no constraints, no potential states) |