Concentrated Masses

Use the Masses tool to create a concentrated mass either on a part or at a point in space.

This is useful when you need to account for the mass of a part when running an optimization using frequency constraints or when analyzing for normal modes.

When gravity is applied during optimization or analysis, the mass will impart a load on the structure.


In most cases you will want to create a concentrated mass part at a distance. You can do this either by creating the mass at a point on your model and then moving it away, or by creating a point in space and then applying the mass to that point.

Create a Mass on a Part

  1. Click the Masses icon on the Structure ribbon.


  2. Click a point on your model.
    The mass is shown as a sphere, and a microdialog appears.


  3. Enter the mass of the concentrated mass part in the text field of the microdialog, and press Enter.
    • To place the concentrated mass at a distance, click the icon on the microdialog. The Move tool appears, allowing you to move the concentrated mass part away from the model. When finished, right-click to exit the Move tool.
    • To place the concentrated mass at a precise location, click the button on the microdialog and enter coordinates for x, y, and z.
    • To connect the concentrated mass part to your model, click the icon on the microdialog. Hover over a point, edge, or face and click to create the connector. Repeat to create additional connectors. Right-click or press Esc when finished.
  4. Right-click and mouse through the check mark to exit, or double-right-click.

Create a Mass at a Point in Space

  1. Select the Points sketching tool on the Geometry tab.


  2. If no sketch plane is active, click on the face of a part to activate one.
  3. Click the Create New Part icon on the microdialog.
  4. Click in the modeling views to create the point.
  5. Right-click twice to exit sketch mode.
  6. Click the Structure tab and select the Masses tool.


  7. Click on the point you just created.
    The mass is shown as a sphere, and a microdialog appears.


  8. Enter the mass of the concentrated mass part in the text field of the microdialog and press Enter.
  9. Click the icon on the microdialog. Hover over a point, edge, or face and click to create the connector. Repeat to create additional connectors. Right-click or press Esc when finished.
  10. Right-click and mouse through the check mark to exit, or double-right-click.

Convert Part to a Mass

Convert a part or parts to a point mass to simplify the simulation and make it run faster.

Right-click on the parts and select Convert to Mass in the context menu. The mass will still need to be attached to the rest of the structure.


Applying Connectors

When you create a concentrated mass part, you will generally want to connect it to geometry features on your model using connectors, which are shown as red lines.



  1. Click the connector icon located on the microdialog for the Masses tool.
  2. Double-click on a concentrated mass part to access the microdialog.


  3. Click on a connector in the modeling views to select it. Selected connectors turn orange. All of the connector lines from a particular concentrated mass are considered a single connector.


  4. Double-click on a connector to enter editing mode.
    When in editing mode, you can add connections to additional geometry features. You can also click to select only those lines that connect the concentrated mass to a particular geometry feature.
  5. Right-click and mouse through the check mark to exit, or double-right-click.