Plot FBD Results

The FBD plot portion of the tab allows you to plot results (Free Body or Resultant Forces/Moments) after the sections have been defined.
  1. From the FBD plot portion of the FBD tab, select the extraction results that you would like to review and display.
    Option Description
    Free body forces/moments Displays the freebody forces/moments on the sections. Depending on the Load component selected, the free body forces represent the forces acting on each of the nodes in the section. Free body forces/moments plots are used to understand the loads acting on a portion of a model (the section), as exerted by the rest of the structure.

    Free body diagrams are used to understand the load transfer points. The extracted free body forces are also used for sub-modeling a portion of the model with a more detailed analysis.

    Resultant forces/moments Calculates resultant forces/moments on the section. For the entire section in equilibrium, the resultant will be summed to zero. Assign a node set to sum up forces only for specific nodes.

    This option can also be used to generate input data for shear and moment (VMT) diagrams and/or to perform load-case screening with Potato plots in HyperView. Two utilities available within HyperGraph also interact with data generated from the Resultant Force and Moment utility.

  2. If Free body forces/moments is selected, activate the Ignore node set check box to ignore all nodes sets in the section when calculating the free body forces.
    A section can be used for the dual purpose of obtaining free body forces or a resultant. For a section that is in equilibrium, the resultant forces of all the nodes in that section is zero. A node set is typically defined for obtaining the resultant on one side of a section. The FBD plot can show free body forces on the entire section, or only on the selected nodes of the node set.
  3. If Resultant forces/moments is selected, use the drop-down menu to determine the grid point force and moment data to extract and utilize for FBD calculations for each node in the selected element.
    Option Description
    Total Extracts and utilizes all element contribution, applied, SPC, and supported MPC grid point data for FBD calculations on the nodes in the selected element set.
    Applied Extracts and utilizes only the applied loads grid point data for FBD calculations on the nodes in the selected element set
    Reaction Extracts and utilizes only SPC and supported MPC grid point data for FBD calculations on nodes in the selected set.

    MPC force and moment data are properly extracted for the following MPC constraint types: RBE2, RBE3, Rigidlink, RJOINT, RROD, and RBAR.

  4. Use the Tolerance entry field to define the cut-off point below which a result quantity is considered zero.
    All calculations are performed with floating point precision and the zero tolerance value is only used to control the output of results to the various formats. This option helps to prevent relatively small values from being output to the result formats.
    Note: To maintain floating-point precision the default is set to 1E-005; modify the value as desired.
  5. Click Apply.
    The specified grid point data is extracted and displayed for visualization in the modeling window.
    Note: Click the Close button (located at the bottom of the tab) to close/exit the dialog.

    All current plots will remain displayed in the modeling window (until they are cleared using the Clear button).