Measuring 2D Inertia

This task explains how to measure the inertia properties of plane 2D surfaces. 

You can measure the area, center of gravity, principal moments, inertia matrix as well as the principal axes.

You can measure the inertia properties of plane surfaces including DMU sections. The area of the surface is also calculated.

Notes: You cannot measure inertia properties of either wireframe or infinite elements.

Step-by-Step Scenario
 

No sample document provided.

  1. Click Measure Inertia . In DMU, you can also select Analyze > Measure Inertia from the menu bar. The Measure Inertia dialog box appears.

  2. Click Measure 2D Inertia  .

    Dialog box options

    • Keep Measure option in the dialog box lets you keep current and subsequent measures as features. Some measures kept as features are associative and can be used as parameters.
      Note: This option is not available in the Drafting workbench.

    • Measure only shown elements: when selected, lets you measure only the elements from the show space.
       
      • Swapping the elements between show and hide spaces does not modify the existing measurements.
      • An update (automatic or manual) of the existing measurements is necessary to modify them after the swap.
      • Select this check box before selecting any elements.

    • An Export option lets you write results to a text file.

    • A Customize... option lets you define what will be computed and displayed in the dialog box.

  3. Click to select a plane 2D surface in the geometry area or the specification tree. The Dialog Box expands to display the results for the selected item. 

  4. Click OK in the Measure Inertia dialog box. If you checked the Keep Measure option in the Measure Inertia dialog box, your measures are kept as features.

 

Customizing Your Measure

You can, at any time, define what will be computed and displayed in the tabs of the Measure Inertia dialog box.

When measuring 2D plane surfaces, in addition to the properties computed by default, you can compute and display the principal axes.
 

  1. Click Customize... in the Measure Inertia dialog box. The Measure Inertia Customization dialog box opens.

    Note: The inertia properties checked here are also the properties exported to a text file. 

  2. Click the appropriate options:

  3. Click Apply or OK in the Measure Inertia Customization dialog box when done.