LineForceWithTwoMassesDemonstrate line force with two point masses using a JointUPS and alternatively a LineForceWithTwoMasses component |
This information is part of the Modelica Standard Library maintained by the Modelica Association.
It is demonstrated how to implement line force components that shall have mass properties. Two alternative implementations are given:
In both cases, a linear 1-dimensional translational damper from the Modelica.Mechanics.Translational library is used as line force between the two attachment points. Simulate this system and plot the differences of the cut forces at both sides of the line force component ("rod_f_diff" and "body_f_diff"). Both vectors should be zero (depending on the chosen relative tolerance of the integration, the difference is in the order of 1e-10 … 1e-15).
Note, that the implementation with the LineForceWithTwoMasses component is simpler and more convenient. An animation of this simulation is shown in the figure below. The system on the left side in the front is the animation with the LineForceWithTwoMasses component whereas the system on the right side in the back is the animation with the JointUPS component.
m |
Value: 1 Type: Mass (kg) Description: Mass of point masses |
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world |
Type: World |
|
---|---|---|
revolute1 |
Type: Revolute |
|
bodyBox1 |
Type: BodyBox |
|
rod1 |
Type: FixedTranslation |
|
jointUPS |
Type: JointUPS |
|
body1 |
Type: Body |
|
body2 |
Type: Body |
|
rod2 |
Type: FixedTranslation |
|
damper1 |
Type: Damper |
|
revolute2 |
Type: Revolute |
|
bodyBox2 |
Type: BodyBox |
|
rod3 |
Type: FixedTranslation |
|
rod4 |
Type: FixedTranslation |
|
damper2 |
Type: Damper |
|
lineForceWithTwoMasses |
Type: LineForceWithTwoMasses |