FreeCAD and Code-Aster/Salome-Meca

[hpon]

Hi,

I'm sure the following idea has been considered before. However, would it be possible and desirable to integrate FreeCAD and Code-Aster/Salome-Meca (and other) into one engineering platform? Are there any steps being taken towards realizing such a pursuit?

/hpon

[jmpoure]

+1

People from French Electrolab club are pointing us this project.
Code-aster is a simulation and resistance testing software.

Here is a short documentation / leaflet:
http://www.code-aster.org/V2/UPLOAD/DOC ... ter_fr.pdf

Code Aster is available from here:
http://www.code-aster.org/

It is released under LGPL by EDF-GDF,
French main energy company.

Code aster is available under Debian SID repositories:

Code: Select all

$apt-get instann code-aster-run code-aster-gui

it is probably the most powerful solution today.

Kind regards,
Jean-Michel

[jmpoure]

Ping!

Code-Aster contains more than 1.500.000 lines of code written in Python and Fortran.
It was used to stress-test French atomic facilities, please have a look or keep an eye to include some bridge in FreeCAD.

You are not going to rewrite 1.500.000 millions lines of code, are you?

[ickby]

check out the fem topics created recently, it is worked on. currently jriegel writes code for pre and post processing in freecad. And thats all that will be in FreeCAD, solvers are introduced by an api which allows the use of diffrent solvers as plugins. So code-aster can be introduced later on.

[jmpoure]

Great!

[sivmah]

Salome-Meca/Code-Aster uses the OpenCASCADE libraries (6.5.4 in the case of Salome-Meca and 6.5.0 in the case of FreeCAD 0.13), so would be possible to export a model to OpenCASCADE BRep format, and then import it into Salome-Meca using OpenCASCADE BRep file import for analysis. I think Salome-Meca supports the same version of python as a scripting engine (2.7), so it should be possible to manage the whole export process including any extra properties supported by FreeCAD via a single python script. At the moment the PythonOCC module (0.5) that goes with OpenCASCADE supports only OpenCASCADE version 6.3.0 which isn't compatible with the current versions used by Salome-Meca or FreeCAD. Salome-Meca/Code-Aster also imports/exports in IGES and STEP formats. PythonOCC v 6.0 is alpha and uses version 6.5.x of OpenCASCADE though so it should hopefully become aligned sometime soon.

I don't think therefore think that there is a need for integration of FreeCAD and Salome-Meca other than keeping the FreeCAD and Salome-Meca versions aligned in the sense that they are compatible import/export wise.

[jriegel]

On Linux distros you have anyway the same versions. Exchanging data between dedicated programs should be no problem. Also I don't thing the BRep format of OCC do not change.

But...

Integration of a FEM system in a CAD modeler is nowadays a MUST! If you do a simulation, look at the stresses and change a radius or an other parameter, you want a automatic recalculation of the fem-mesh and the loads. For 80% of the mechanical cases a CAD integrated FEM is good enough. Gearing up special cases (like car crash) you will have always specialized programs.

For FEM (or CAM or Robotik) the 80/20 rule applies:
For 80% of the cases you need only 20% of the functionality.

[sivmah]

The thing is that you don't need to settle for 80% and you don't need to reinvent the wheel - you can have 100% for free by installing Salome-Meca as a companion program, and controlling it including regeneration of meshing and loads from FreeCAD using Python. The main app could (and probably should) therefore reside in FreeCAD which would generate drawings, idealsation etc, and possibly reports for standard analysis cases that are supported. Although Salome-Meca runs only on Linux, Windows users can also access Code-Aster (analysis engine in Salome-Meca) running on a server http://www.alneos.com/en/download/codea ... -the-cloud, and there are some Salome Windows binaries http://www.salome-platform.org/download ... nt-version .

For example, you could create a bridge deck design application for prestressed concrete bridge decks with insitu reinforced concrete deck slab, where you create a schematic arrangement of setting out of the prestressed beams, and support abutment bearings, with the standard precast beam etc. designation entered, and choose to have your app generate either a grillage or a FEM model and loadings, and create an analysis model in Salome-Meca. You would then refine the analysis and complete it in Salome-Meca, use a third party commercial prestressed concrete design package, and once the section sizes selected have been proven, have FreeCAD generate drawings including sections and details some of which are automatically generated, and some of which are manually added.

The reason for using Salome-Meca as a companion package to which FreeCAD is a front end rather than trying to do too much in FreeCAD itself is for maintainability reasons. Salome-Meca is an extremely powerful, comprehensive and professionally maintained FEM, stress visualisation, reporting and analysis engine. It has meshing tools, supports various import/export formats, has various visualisation and reporting tools, and even an equivalent of make (YACS) for managing changes and dependencies in input files. In real life, it is also necessary to use other commercial design and analysis packages for specialist applications. There are a lot of very good FEM, analysis and design packages out there (the majority of which are commercial) and Salome-Meca is one of them. If you try to do too much in FreeCAD by re-inventing what is already out there, then you will end up with something second rate, with limited functionality, and something which will be unmaintainable because there is insufficient resourcing for maintenance.

The big potential I see in FreeCAD for FEM and analysis is format compatibility and cross application python scripting with Salome-Meca and other packages, and the fact that it can be used to automatically generate both drawings, and analysis models/data, and also other output like bills of materials, weights etc. While the market is crowded with very good modelling, analysis and design packages, what is lacking currently in the process is the automation of drawing production, and production of bills of materials and their integration with the design process. It is really strange and nonsensical that while we have sophisticated 3D analysis and simulation and a high degree of automation, we still produce drawings by manually drawing out lines using a line drawing CAD package like AutoCAD, and manually add up and measure quantities for bills of materials that go into contract documents, when these things are the things that are the most tedious and repetitive operations and should be automated first. This is the real bottleneck in the design process nowadays, rather than analysis or design, particularly in the civil, structural and architectural fields where the structures, drawings representing them, and contract documents created to construct them are very complex and voluminous.

I see the big potential for FreeCAD in CAD drawing and BoM automation, and as a container for specific integrated design applications which leverage this automation by leveraging where necessary other packages like AutoCAD or DraftSight for finishing drawings, Salome-Meca for analysis and exporting into other analysis formats, and custom python scripted output for import into other commercial packages. The problem with CAD and design in open source development is that it requires a high degree of specialisation in a particular field, which means the time and resources that contributors can devote to development is very limited. In this context, it is important to leverage existing applications (open source, and commercial) where necessary, and to focus effort where it is really necessary.

[jriegel]

I'm afraid, I have to disagree.

You always free to use Salome as FEM package with FreeCAD models. Thats a pretty normal way to do it.
Remote control something like Salome is practically nonsense! Nothing fit together. Not the data model, not the user interaction, not the platform. So you will end up programing around the differences in both packages and no one is satisfied. So simply just use Salome for FEM if its fits your needs.

I also have to disagree with Drawing automation. IMO its pointless to spend man years of programming to automate putting 3D designs onto paper, obeying standards made for paper and pencil. I think the world (at least mine) moved past that point a long time already. I know the civil engineering is still very 2D focused, but that will also end not far away.