CAD Parameter Update

Updating CATIA and NX parameters to generate modified CAD designs.

It is often required to make CAD design changes as part of an optimization or design study. Making such changes to the original CAD files often requires scripting and customization. CATIA/NX parameters can now be easily modified directly in HyperMesh. The changes made to the CAD file in CATIA/NX are saved and automatically reloaded. A valid CATIA/NX installation and license are required.

An environment variable CATIA_INSTALLATION_DIR pointing to the CATIA installation is required for importing CATIA parameters in HyperWorks.

Example: CATIA installation located at C:/Program Files/Dassault Systemes/B30

CATIA_INSTALLATION_DIR: C:/Program Files/Dassault Systemes/B30

Or, at the HyperWorks command window level, it can be set as below:

set ::env(CATIA_INSTALLATION_DIR) "C:/Program Files/Dassault Systemes/B30"

Limitations and Restrictions

This process involves the following considerations:
  1. CATIA/NX files must be imported using the Parts option.
  2. Imported CATIA/NX parameters must be enabled with the proper name prefix.
  3. To enable parameter importing in NX, the <ALTAIRHOME>/io/afc_translators/bin/<platform>/ug_reader.ini file must be updated. Also, make sure all other options are set to their relevant states or values.
    Note: This is important because this file is used during the reload operation. If not defined properly, the reimported model may not be as expected.
  4. To enable parameter importing in CATIA, the <ALTAIRHOME>/hwdesktop/io/afc_translators/bin/<platform>/ct_reader.ini file must be updated. Also, make sure all other options are set to their relevant states or values.
    Note: This is important because this file is used during the reload operation. If not defined properly, the reimported model may not be as expected.
  5. Performing this operation clears the undo/redo history.
  6. All information stored in the part(s) associated with a modified parameter is purged.
  7. There is no support for automatic remeshing, or the application of loads/BCs.

Associated Tasks

You can specify whether to perform automatic updating when making parameter changes, or to delay updating using the CAD update tool. You can set this option in HyperMesh or HyperWorks by selecting Preferences > CAD Options from the menu bar, then placing a check in the Show Updates Immediately checkbox.

If you are using HyperWorks, select File > Preferences > Geometry > CAD Section.

Live Parameter Update

If you set the preference to allow immediate updates, changing any relevant parameter values (from within EE, via a script, and so forth) will immediately execute the update operation. If the CATIA/NX update operation is successful, the original CATIA/NX file is overwritten and parts associated with the modified parameter are purged and reloaded.

Delayed Parameter Update

If you set the preference to not allow immediate updates, changing any relevant parameter values (from within EE, via a script, and so forth) will not execute the update operation. Instead, you can use the CAD update tool to update parameters when necessary.

Results

After performing the update operation, the modified CATIA/NX CAD file is reloaded into HyperMesh. Also, a cad_updated.msg file is created in the HyperMesh start directory, which contains details about the update operation.


Figure 1.

Version History

2019.1 – Added NX CAD parameter support.

2021 – Added CATIA CAD parameter support (CATIA V5 format).