modelLineForceWithMass
Extends from Interfaces.LineForceBase (Base model for line force elements).
Information
This component is used to exert a line force between the origin of frame_a and the origin of frame_b by attaching components of the 1-dimensional translational mechanical library of Modelica (Modelica.Mechanics.Translational) between the two flange connectors flange_a and flange_b. Optionally, there is a point mass on the line connecting the origin of frame_a and the origin of frame_b. This point mass approximates the mass of the force element. The distance of the point mass from frame_a as a fraction of the distance between frame_a and frame_b is defined via parameter lengthFraction (default is 0.5, i.e., the point mass is in the middle of the line).
In the translational library there is the implicit assumption that forces of components that have only one flange connector act with opposite sign on the bearings of the component. This assumption is also used in the LineForceWithMass component: If a connection is present to only one of the flange connectors, then the force in this flange connector acts implicitly with opposite sign also in the other flange connector.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | animateLine | true | = true, if a line shape between frame_a and frame_b shall be visualized |
| Boolean | animateMass | true | = true, if point mass shall be visualized as sphere provided m > 0 |
| SI.Mass | m | 0 | Mass of point mass on the connection line between the origin of frame_a and the origin of frame_b |
| Real | lengthFraction | 0.5 | Location of point mass with respect to frame_a as a fraction of the distance from frame_a to frame_b |
| Advanced | |||
| SI.Distance | s_small (from LineForceBase) | 1e-10 | Prevent zero-division if distance between frame_a and frame_b is zero |
| Advanced › If enabled, can give wrong results, see MultiBody.UsersGuide.Tutorial.ConnectionOfLineForces | |||
| Boolean | fixedRotationAtFrame_a (from LineForceBase) | false | = true, if rotation frame_a.R is fixed (to directly connect line forces) |
| Boolean | fixedRotationAtFrame_b (from LineForceBase) | false | = true, if rotation frame_b.R is fixed (to directly connect line forces) |
| Animation › if animateLine = true | |||
| Types.ShapeType | lineShapeType | "cylinder" | Type of shape visualizing the line from frame_a to frame_b |
| Types.ShapeExtra | lineShapeExtra | 0.0 | Extra parameter for shape |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Interfaces.Frame_a | frame_a (from PartialTwoFrames) | Coordinate system a fixed to the component with one cut-force and cut-torque | |
| Interfaces.Frame_b | frame_b (from PartialTwoFrames) | Coordinate system b fixed to the component with one cut-force and cut-torque | |
| Modelica.Mechanics.Translational.Interfaces.Flange_a | flange_b | 1-dim. translational flange (connect force of Translational library between flange_a and flange_b) | |
| Modelica.Mechanics.Translational.Interfaces.Flange_b | flange_a | 1-dim. translational flange (connect force of Translational library between flange_a and flange_b) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Distance | length (from LineForceBase) | Distance between the origin of frame_a and the origin of frame_b | |
| SI.Position | s (from LineForceBase) | (Guarded) distance between the origin of frame_a and the origin of frame_b (>= s_small)) | |
| SI.Position[3] | r_rel_0 (from LineForceBase) | Position vector from frame_a to frame_b resolved in world frame | |
| Real[3] | e_rel_0 (from LineForceBase) | Unit vector in direction from frame_a to frame_b, resolved in world frame | |
| Types.SpecularCoefficient | specularCoefficient | world.defaultSpecularCoefficient | Reflection of ambient light (= 0: light is completely absorbed) |
| SI.Length | lineShapeWidth | world.defaultArrowDiameter | Width of shape |
| SI.Length | lineShapeHeight | lineShapeWidth | Height of shape |
| Types.Color | lineShapeColor | Modelica.Mechanics.MultiBody.Types.Defaults.SensorColor | Color of line shape |
| Real | massDiameter | world.defaultBodyDiameter | Diameter of point mass sphere |
| Types.Color | massColor | Modelica.Mechanics.MultiBody.Types.Defaults.BodyColor | Color of point mass |