In Simcenter Testlab Geometry (formerly LMS Test.Lab Geometry), it is possible to import a CAD file to the geometry instead of creating a geometry from scratch. Most CAD packages are able to export CAD geometry which the user can save locally.
File formats that are importable include:
Stereolithography files (both ascii and binary)
Universal files
Nastran files
Virtual.Lab files (.VL2TL)
To import a CAD geometry into Simcenter Testlab, open the Geometry workbook.
Go to Tools -> Add-ins and turn on “Geometry”.
Figure 1: The Geometry add-in uses 16 tokens.
Browse to the geometry file in the file tree on the left of the screen.
Figure 2: Expand the geometry file directory to get to the component level.
Click on the component(s) to import. Then select “Import Geometry”. This will overwrite any existing geometry in the project.
Figure 3: Import the geometry.
The CAD geometry file will import. The geometry that is imported can be used like any other geometry, from channel setup to animating mode shapes, etc.
Figure 4: Top: The .stl file is imported. Bottom: The .stl file can be used in channel setup to map nodes to channels.
Often, the imported CAD geometry file contains many more nodes than locations that will actually be physically measured. If a node does not have associated measured data, it does not automatically animate.
For example, the .stl file of the F16 aircraft that was imported in the example above has 1172 nodes. It is rare that 1172 measurement points would be taken so that every node in the geometry can be animated.
It can be confusing to only see the measured nodes moving and not the other nodes in the geometry – therefore animation extensions like “Automatic Topological” and “Automatic Geometrical” can be used. These extensions slave nodes together in the geometry so that more nodes animate than just the ones that have measured data associated with them:
Automatic Topological will look for nodes that are connected to other nodes. A connected node means that a line was drawn between the nodes in the Geometry workbook. The software algorithm animates any nodes that are connected to nodes with measured data associated with them.
Automatic Geometrical will look at nodes that are near one another in space. The software algorithm then slaves the nodes together and animates the nodes.
To use these animation extensions, right click in a geometry window, go to “Animation Settings” and select either “Automatic Geometrical” or “Automatic Topological”.
Figure 5: Turn on visualization expansions.
Look at the video below to see the difference between no modal expansion, Automatic Geometrical, and Automatic Topological.
Expanding the animation can be a great tool for reporting to make mode shapes and operational deflection shapes look more realistic.
