Cylindrical
Cylindrical joint (2 degrees-of-freedom, 4 potential states)
Library
Modelica/Mechanics/MultiBody/Joints
Description
Joint where frame_b rotates around and translates along axis n which is fixed in frame_a. The two frames coincide when "phi=revolute.phi=0" and "s=prismatic.s=0". This joint has the following potential states;
- The relative angle phi [rad] around axis n,
- the relative distance s [m] along axis n,
- the relative angular velocity w [rad/s] (= der(phi)) and
- the relative velocity v [m/s] (= der(s)).
They are used as candidates for automatic selection of states from the tool. This may be enforced by setting "stateSelect=StateSelect.always" in the Advanced menu. The states are usually selected automatically. In certain situations, especially when closed kinematic loops are present, it might be slightly more efficient, when using the "StateSelect.always" setting.
In the following figure the animation of a cylindrical joint is shown. The light blue coordinate system is frame_a and the dark blue coordinate system is frame_b of the joint. The black arrow is parameter vector "n" defining the cylinder axis (here: n = {0,0,1}).
Parameters
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_animation | animation | = true, if animation shall be enabled (show cylinder) | Scalar | true |
mo_n | n | Cylinder axis resolved in frame_a (= same as in frame_b) | Vector of size 3 |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_cylinderDiameter | cylinderDiameter | Diameter of cylinder | Scalar | |
mo_cylinderColor | cylinderColor | Color of cylinder | Vector of size 3 | |
mo_specularCoefficient | specularCoefficient | Reflection of ambient light (= 0: light is completely absorbed) | Scalar |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_stateSelect | stateSelect | Priority to use joint coordinates (phi, s, w, v) as states | Structure | |
mo_stateSelect/choice1 | StateSelect.never | Number | 0 | |
mo_stateSelect/choice2 | StateSelect.avoid | Number | 0 | |
mo_stateSelect/choice3 | StateSelect.default | Number | 0 | |
mo_stateSelect/choice4 | StateSelect.prefer | Number | 0 | |
mo_stateSelect/choice5 | StateSelect.always | Number | 0 |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_prismatic | prismatic | prismatic | Structure | |
mo_prismatic/fixed | fixed | Cell of scalars | ||
mo_revolute | revolute | revolute | Structure | |
mo_revolute/fixed | fixed | Cell of scalars | ||
mo_s | s | s | Structure | |
mo_s/fixed | fixed | Cell of scalars | true | |
mo_s/start | start | Cell of scalars | ||
mo_phi | phi | phi | Structure | |
mo_phi/fixed | fixed | Cell of scalars | true | |
mo_phi/start | start | Cell of scalars | ||
mo_v | v | v | Structure | |
mo_v/fixed | fixed | Cell of scalars | true | |
mo_v/start | start | Cell of scalars | ||
mo_w | w | w | Structure | |
mo_w/fixed | fixed | Cell of scalars | true | |
mo_w/start | start | Cell of scalars | ||
mo_a | a | a | Structure | |
mo_a/fixed | fixed | Cell of scalars | true | |
mo_a/start | start | Cell of scalars | ||
mo_wd | wd | wd | Structure | |
mo_wd/fixed | fixed | Cell of scalars | true | |
mo_wd/start | start | Cell of scalars |
Ports
| Name | Type | Description | IO Type | Number |
|---|---|---|---|---|
frame_a | implicit | Coordinate system a fixed to the component with one cut-force and cut-torque | input | 1 |
frame_b | implicit | Coordinate system b fixed to the component with one cut-force and cut-torque | output | 1 |