Analysis Solution

What You Will Learn With These Use Cases

These use cases are intended to help you make your first steps in creating a new Analysis Feature using the Feature Modeler and Analysis Infrastructure frameworks.

The main intent is to explain:

• How to define a new analysis workbench.
• How to define features and how to store their definitions as Start-Up's  in a startup Catalog file.
• How to reuse these Start-Up's to create feature instance by implementing an Analysis transition. The transition will be introduced in order to customize the document for an analysis kind.
• How to Implement the import of an external data inside the Analysis document.
• How to manage the access to the physical data that are associated to this kind of analysis.

These use cases include some knowledge from various V5 Frameworks, such as the Feature Modeler framework, or the Dialog and DialogEngine Frameworks. Their intent is to focus on the use of the Analysis Infrastructure frameworks. A prerequisite knowledge of other Frameworks may be required to fully understand this use case. Some links with other CAA use cases will help you navigate among them.

Before getting to the tutorials, it is important to get an understanding of the use case scenario. This is the goal of the next section. 

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The Use Case Scenario

An external solver computes velocity vectors expressed at the node of a mesh. Two scenarios can be taken into account:

• Use some interactive functionality of CATIA in order to generate a mesh, and define your preprocessing data, then export those data for the external as solver (as explain in the export use case) and integrate on the solution set the access to the computed data.
• Integrate the import of the mesh as defined in the input file of the solver and then give access the result file.

The use case will explain how to integrate these data inside the CATIA application in order to visualize the following picture by focusing on the second scenario.

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The Use Cases

This section will describe the different tasks to perform to achieve the scenario described before.

What Do These Use Cases Do

The final intent of this use cases is to create some analysis features to manage Aero Dynamic Data. This is an end-to-end integration. At the end of this use case "Tour", you should hardly notice any difference between this Feature and an original V5 Analysis feature as defined for the "Structural Analysis" Applications. We will focus on three analysis features for this scenario.

1. The "Links manager" feature that is dedicated to keep all the links to imported documents. (Is this scenario, just the mesh). For this we will  use the "SAMFeatureLinkFile" or "SAMFeatureLink" basic startup. This link management includes:
   • The update integration to know if the file is modified since last consultation of the document (just  for SAMFeatureLinkFile)
   • The data management of the file if the analysis document is moved (Send-To, Edit-Links and Search-Order capabilities) for both startup's. 
2. The "Aero" MeshPart feature dedicated to integrate the imported mesh inside the analysis document. More generally, the MeshPart is used to keep the meshing specification that will produced as result the mesh (Nodes and Finite Elements). 
3. The "AeroDynamic" SolutionSet feature dedicated to keep the link to the result file and the access to its contents for visualisation.

The first feature will be created "as defined" inside the Analysis Infrastructure (by instantiating an existing late type) and the two others will be created by derivation of existing startup (respectively MSHPart and SolutionSet) in order to assume specific implementations.

Consequently, this use case includes tree main modules :

Fisrt, CAAAniWb.m for the user interface required for this scenario. This use case defines a new analysis workbench associated to this scenario.

Then, CAAAniCatalog.m for the feature catalog definition, that create the "Aero" MeshPart and "AeroDynamic" SolutionSet feature StartUp.

Then, CAAAniAeroDTransition.m, that:

• Instantiates the StartUp by implementing a transition
• Imports an external mesh (This step can also be done by creating directly a mesh inside CATIA Applications).
• Implements the required interfaces to integrate the meshing and the solution feature inside CATIA
  • The CATISamExplicitation interface for all analysis features.
  • The CATICharacCollector interface that allow the access to physical data that deals with this Solution Set.

We will also see that some other interactive behavior, such as Analysis Visualization. 

About Import

This chapter will focus on the feature created for managing the import, the MSHPart. For our scenario, we just need a to have a mesh, but a mesh is a result view of the analysis infrastructure (like all the field model objects). These result objects must be created and modified by implementing some specific interface on some analysis feature, this will manage the results object life cycle (including Undo/Redo) and the way to access them. Working directly on result view objects may produce some unpredictable results.

• To create a mesh, implement the CATIMSHMesher interface on a feature created by derivation of MSHPart.
• To define physics on a mesh, implement the CATISamExplicitation interface on a feature created by derivation of MSHPart. By default, when creating a meshpart feature, an explicit set (with physical type MESH SET) is created. The implementation of CATISamExplicitation will create under this set two other sets, one with physical type NODES for nodes definition and one with physical type ELEMENTS for finite elements definition. In this last set, elements will be created according to their element type and some physics can be defined at this level.

1. Create a dedicated interface (CAAIAniAeroImport) which is implemented on the object representing the imported document type.
2. The mesher then calls the first method of the interface to create the mesh. That method stores in the implementation object the list of nodes, elements and physical types. 
3. The TranslateToFieldModel() calls the second method to create the explicit nodes and elements using the stored information.

All these interfaces, are used by Dassault Systemes implementation of CATIBuild (for the Update of any analysis features).

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Keeping a Link to an External File from a Feature Object.

The capability to keep a link to input or output files of external solver can be very useful in the analysis domain. To do this, some special feature attributes exist. They are called tk_external.

To use them, you need to simulate that your file is a CATDocument. Your file type need only to have a defined suffix. For this, implement the CATIPersistent interface on your file type. All the methods have to be implemented with dummy software. In order, to get the CATDocument from your file, use CATDocumentServices::Open method. From the CATDocument, we have to get the CATILinkable Object (implemented by ObjectModelerBase for any kind of CATDocument). 

Then you can use the CATILinkableObject interface in order to valuate or read the tk_external attribute. All required information for valuating attributes can be found at the Reference [1].

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Where Each Object Will Interact With User Interface.

All this module have to be compiled in order to be taken into account for CATIA Interactive applications. This will customize the user interface of Analysis Workbenches by adding an Aero Dynamic line in the "New Analysis Case" window. You can also enter an Analysis Workbench by creating a new Analysis Document, the same window will appear. This section presents each object that correspond to specific interface implementation and its interaction with the user interface according to the final scenario. 

Then, an import item will appear under the contextual menu of the Links manager object.

CATISamAnalysisTransition Customizes an new analysis document with an Analysis Case and a specific Solution Set.
CATISamImportDefine Is NOT implemented on the file suffix. Creates the mesh Part for importing data Creates the link to the external file. Customizes the Import command with a dedicated file selection for the domain. Can customize the import with an user dialog. This import command is a contextual menu on the Links Manager object.
CATIPersistent Is Implemented on the file suffix. Allow you to manage the file as a CATDocument in order to keep the link.
CATIMSHMesher Is implemented on the meshpart to import the mesh inside the meshing container. CATISamExplicitation Is implemented on the meshpart to link the mesh and its Field model physical definition. CATICharacCollector Is implemented on the Solution Set  to import the results and keep it up_to_date according to the Update mechanism. Is used by CATIA Analysis Visualization package.

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Where to Find These Use Cases

Code for these use case is contained in the CAAAniWB.m, CAAAniCatalog.m and CAAAniAeroDtransition.m modules of the CAAAnalysisInterfaces.edu framework.

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In Short

The CAAAnalysisInterfaces.edu sample shows how to add a new Analysis feature inside CATIA Analysis Infrastructure.

You can now successively go to:

• Creating Analysis Startup's in a Catalog file.
• Customize an analysis document (CATISamAnalysisTransition implementation).
• Implement an Import of external format document (CATIPersistent, CATISamImportDefine implementations).
• Implement a physics behavior (CATICharacCollector and CATISamExplicitation implementations).
• Create an image for the velocity

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References

History

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