Personal tools
You are here: Home Forum Install & build Trouble picking an inside face in GEOM

Trouble picking an inside face in GEOM

Up to Install & build
  • Trouble picking an inside face in GEOM

    Posted by JMB at August 11. 2008
    Hello,

    I have imported a solid CAD model via STEP import.  I want to explode some faces selectively.  One of them is an interior face that I am not able to click on, because exterior faces get in the way.  The best way to describe my situation is with an analogy.

    Suppose I have a solid model that looks like a wine (or crude oil) barrel standing upright.  Assume also that it has thick walls such that it has exterior as well as interior faces.  So this barrel has 6 faces. Two circular faces for each of the 2 ends and 2 cylindrical faces; one inner and one outer.  Now imagine that I want to a select the inside surface of the barrel's top (so I can apply an internal pressure upward).  How do I pick this inner surface because clicking causes the outside cylinder of the barrel (or the barrel bottom's outer face) gets selected ?  Is there any way to cycle through each surface that may be under another and also that lies under the mouse cursor ?

    Any clues would be helpful.  Of course in the worst case I could explode all 6 faces, then pick that one I want when it gets highlighted.  This becomes very tedious when one has a complex model with hundreds of faces!  Thank you.

    Regards,
    JMB
    • Re: Trouble picking an inside face in GEOM

      Posted by JMB at August 11. 2008
      Hello,

      I forgot to mention in my previous message that, I tried the clipping feature such that I cut the barrel in half, but I am still unable to pick that inside top circular face.  Even in the clipped view the mouse pointer does not pick the surface I want.  Is this now seeming like a bug?

      Regards,
      JMB
    • Re: Trouble picking an inside face in GEOM

      Posted by Saint Michael at February 26. 2013

      Hello Aroj

      I doubt that the following is what you need, but in SALOME you can store your mesh in STL format file (only 2D mesh is stored) and then import this file into a shape. The result shape is a shell of triangular faces.

      As about creation of a group of volumes from a group of nodes, there is no such a ready-to-use function in SALOME, but it's possible to create such groups using Python scripting of SALOME. It's rather easy and I can assist you in this if you are interested in.

       

      St.Michael
      • Re: Trouble picking an inside face in GEOM

        Posted by Aroj Bhattarai at February 26. 2013

        Hello St. Michael,

         

        Thank you for your generosity on my problem. For sure I would like to accept your support. Can you please write me how I can do such creation of volume elements using Python script in SALOME?

         

        With regards,

         

        Aroj

         

    • Re: Trouble picking an inside face in GEOM

      Posted by Aroj Bhattarai at February 25. 2013

      Hello St.Michael and Vadim,

      Thank you for your quick response. I guess the procedure you suggested is referring for a model with a geometrical data. However, I am provided a model with a ready-made 2D surface mesh (a complete mesh without geometrical data and without any group of faces and nodes), which I converted into a 3D mesh (Type = Tetrahedron (Netgen) and Number of volumes = 30316). In order to assign the boundary condition I selected the nodes manually (one by one) and created some separate groups. Simulation worked for a single material on the whole 3D mesh.

      Problem: Selection of the inner elements underlying the faces in a 3D mesh.

      I am trying to implement more than one material in the single 3D mesh. For this, I tried to create groups of volume separately on different part of the mesh. Now my problem is that I can select the elements (volume) on the face but the element (volume) underlying the surface are not completely selected. I am not able to select  around 10000 elements in total which are in between the faces of the mesh. How can I select those missing elements?

      Thank you in advance for your time and consideration to my problem.

      With regards,

      Aroj 

    • Re: Trouble picking an inside face in GEOM

      Posted by Saint Michael at February 26. 2013

      Hi Aroj

      Here is the script. It supposes that your mesh with nodal groups is already loaded and Mesh module is activated. Find some more comments within the script.

      St.Michael

      Attachments
      • Re: Trouble picking an inside face in GEOM

        Posted by Aroj Bhattarai at February 27. 2013

        Hello St. Michael,

         

        I am heartily thankful for your support. Implementation of Python in SALOME is a quite new topic for me. Can you please suggest me some helpful documentation?. Wish you have wonderful days ahead...:)

         

        Best regards,

         

        Aroj

         

        • Re: Trouble picking an inside face in GEOM

          Posted by Saint Michael at February 27. 2013

          Hi Aroj

          I see two practical ways to learn Python scripting of SALOME:

          1) To do something in GUI and dump a study to a Python script (menu File/Dump Study).

          2) To analyze sample scripts referred from GUI documentation.

          You can consult as well Python Interface chapter of SMESH GUI doc http://docs.salome-platform.org/salome_6_6_0/gui/SMESH/smeshpy_interface_page.html

           

          St.Michael

           

          Previously Aroj Bhattarai wrote:

          Hello St. Michael,

           

          I am heartily thankful for your support. Implementation of Python in SALOME is a quite new topic for me. Can you please suggest me some helpful documentation?. Wish you have wonderful days ahead...:)

           

          Best regards,

           

          Aroj

           

           

    • Re: Trouble picking an inside face in GEOM

      Posted by Saint Michael at February 22. 2013

      Hello Aroj

      If I were in your place I would create a group containing only the face(s) of interest. "Create Group" dialog allows selecting and hiding faces that are in the way and prevent selecting the face of interest.

      St.Michael

    • Re: Trouble picking an inside face in GEOM

      Posted by Vadim SANDLER at February 22. 2013

      Hello Aroj,

       

      In the "Sub-shape Selection"  (New Entity -> Explode operation) and in the "Create Group" dialog boxes there is indeed such a possibility - there is a button "Hide selected" that allows to hide some selected sub-shapes; this allows to access internal sub-shapes.

       

      Regards,

      Vadim.

    • Re: Trouble picking an inside face in GEOM

      Posted by Aroj Bhattarai at February 22. 2013

      Hello JMB,

       

      As per the problem you posted did you get the appropriate solution? I am working on the similar problem but of the different model. Can you please share me the solution procedure that you followed and help me to overcome the situation?

       

      With regards,

      Aroj

    • Re: Trouble picking an inside face in GEOM

      Posted by Saint Michael at February 25. 2013

      Hello Aroj

      In this case a solution can be as follows.
      (1) You create a GEOM object which includes, even partially, 3D elements of one material only.
      (2) Then you create a mesh "Group on filter" using "Lying on geom" criterion, with Threshold = your GEOM object.

      If you have only two materials, the second group can be created the same way but using negation of the mentioned above criterion.

      St.Michael

      • Re: Trouble picking an inside face in GEOM

        Posted by Aroj Bhattarai at February 26. 2013

        Hello St. Michael,

         

        Thank you very much for your reply. Creation of GEOM object as per the Mesh model could be an alternative procedure. However, Is there any way that we can convert the mesh file into geometry using any user friendly CAD softwares? I tried to do so with the aid of Autodesk Inventor 2013 but could not succeed.

         

        Additionally, is there any possibility to create groups of volume elements in accordance to the groups of nodes in Salome? Because in my 3D mesh I have 3 different sets of nodes and would like to assign three different material properties by creating three different groups of volume as per the groups of nodes.

        Hope to get your convenient reply.

         

        With regards,

         

        Aroj

         

Powered by Ploneboard
Document Actions