PolyBeams

A PolyBeam is a series of beams that is defined through a series of points. PolyBeams can be used to represent slender beams, cables, and hoses.

Create PolyBeams Using the PolyBeams Tool

  1. From the Model Browser, select the system to which the PolyBeam entity is to be added.
  2. Right-click on a system in the Model Browser and select Add > Force Entity > PolyBeam from the context menu.
    OR
    Right-click on a PolyBeam folder in the Model Browser and select Add PolyBeam from the context menu.
    OR
    From the Model ribbon, Beams tool set, click the PolyBeams icon.
    The PolyBeam guide bar is displayed.
  3. In the Points collector, select two or more points.
    • Select points in the modeling window.

      OR

    • On the guide bar, click the Advanced Selector and make your selection in the Model Tree.
  4. Optional: To deselect an already selected point, use Shift + Left click.
  5. Optional: Click on Add a deformable curve to create a deformable curve associated with the polybeam.
    Note: A deformable curve can be used in contacts.
  6. Once the selections are made, create the PolyBeam using one of the following methods:
    1. Click on the guide bar OR click the button that appears at the mouse location in the modeling window.

      A Polybeam will be created and a microdialog with properties appears in the modeling window.

      OR

    2. Click to create the entity and start adding another entity.
  7. Optional: Click to reset the entity selections and select new entities.
    Once a PolyBeam has been added to the model, it will automatically be displayed in the browser area and its Entity Editor will be displayed in the Entity Editor area.

Edit Polybeams

A polybeam has circular cross sections throughout its length. The mass of the polybeam is distributed across dummy bodies that are located at each point in the polybeam. A polybeam is defined by specifying the cross-sectional properties of the beam and the locations of the points in the beam. MotionView automatically generates the actual beam elements and dummy bodies.

  1. Edit the connectivity using the PolyBeam tool:
    The connecting points of a PolyBeam can be edited using the PolyBeam tool.
    1. Select the PolyBeam to be edited either through the modeling window or the Model Browser.
    2. Click on the PolyBeam tool icon in the Model ribbon.
      A guide bar for the PolyBeam appears along with a microdialog with properties (OD, ID, E and rho) in the modeling window.
    3. Activate the Points collector in the guide bar that needs editing.
    4. Pick more points either from the microdialog or the Advanced Selector .
    5. To deselect a selected point, use Shift + Left click.
  2. Using the Entity Editor
    1. Select the PolyBeam to be edited either through the modeling window or the Model Browser. The Entity Editor is automatically displayed.
    The Entity Editor displays the properties that can be edited (see the table below). All properties of the PolyBeam can be edited from the Entity Editor.
    Tip: Delete points by opening the View Entities dialog and clearing their respective check boxes.
    Note: PolyBeam only has circular cross sections.
    Table 1. Force Properties
    Property Description
    General
    Label Descriptive label for the entity.
    Varname Variable name of the entity.
    ID Integer identifier.
    Active Active state of the entity. True or False. Entity is deactivated if False.
    Properties
    Points Connecting points defining the polybeam. Activate the collector to pick additional points, deselect (Shift + Left click). Use the hamburger menu on the left to see the list of points and deselect.
    Type Read only. Currently only the Circular cross section type is supported.
    Density (rho) Mass density of the polybeam.
    Modulus of Elasticity (E) Youngs Modulus.
    Modulus of Rigidity (G) Modulus of Rigidity or Shear modulus.
    Outer Diameter (OD) Outer diameter of the circular cross section.
    Inner Diameter (ID) Inner diameter of the circular cross section.
    AS Correction factor for shear deflection.
    CRatio Damping to Stiffness matrix ratio. The damping matrix for the polybeam is computed by multiplying the stiffness matrix by the CRatio.
    Appearance
    Visible Control the visibility of the entity icon.
    Color Set the color of associated graphics (Tube) of the polybeam.
    Mesh Set the mesh option for the associated graphics.
    Shade Set the shading option for the associated graphics.
    Note & Tags
    Note Optional descriptive note.
    Attachment Candidates Add tags for the entity as possible candidate for attachments to Systems/Assemblies/Analyses.