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Alright, thanks for the feedback.
As soon as you have some info, let us know if we can further help.Best,
Hugo
Dear Alison,
Again, that’s a nice project.
I replied partially on the topic: https://www.sofa-framework.org/support/forum/topic/how-to-break-the-spring-between-mesh/I did not thought about it, but there is a very basic example of cutting in examples/Demos/TriangleSurfaceCutting.scn. Is that close to what you want to do?
About the tearing, @chrijopa could maybe help ?
Cheers,
Hugo
Dear Michel @michelodu and Cece,
Remi confirmed me that he sent you the scene.
Did it help you or do you need any further support on this topic?Cheers,
Hugo
Hi Francesca (again),
I think we answered the question about how to import vtk files in SOFA.
If you have any further questions, do not hesitate to create a new topic!Cheers,
Hugo
Dear Nithin,
Sorry for the delay on your topic.
However, there is already a topic about this: https://www.sofa-framework.org/support/forum/topic/how-to-construct-a-grasper-scenewith-force-feedback/Let us know if it doesn’t fit what your need.
Cheers,
Hugo
Hi Alison,
This is a very challenging project that you have here! Simulating deformable object is ok, with dynamic breaking of springs ok, but then do dynamic remeshing from the computation of the stress. It starts growing in term of complexity!
About how to break individual springs, you would need to create a component inheriting from meshSpringFF where you implement a function “removeSpring” doing the opposite than addSpring function (line 50 in meshSpringForceField.inl). You could then call this function when a specific event occurs.
We are currently working on dynamic remeshing based on VM stress as well. But this is really a on-going work. But I am no expert on the remeshing subject. @hpbui may be able to help ?
Cheers,
Hugo
Hi Wong,
First, detecting wheter a model is colliding with another one can be implemented in any component (you can write your own) in the handleEvent function. All you need to do is to detect the CollisionEndEvent, and when the event is detected you check the output of the collision detection (e.g. using collision::NarrowPhaseDetection::DetectionOutputMap). You can find an example of this in modules/SofaValidation/EvalSurfaceDistance.inl. I never did it myself, but I guess from this vector of DetectionOutputMap, it should be possible to detect what models are colliding each other.
To fix any model, you can use the FixedConstraint. This component ensures that the nodal positions do not change. If you fix a rigid node, and that you map a collision model on this node, this will work.
Hope this helps (sorry I am no collision expert).
Best,Hugo
Hi Francesca,
I’m afraid there is some bugs in the Modeler itself.
We are working on it.
When you work on a scene in the Modeler, you can still export it (.scn) and use it in runSofa directly.
Sorry for the inconvenience.Hugo
Dear Francesca,
If you want to have a deformable 3D object (like the tongue), you need to have a 3D deformation model. Therefore, you will need a 3D representation of your object: a triangle mesh only represents the surface (2 dimensions) of the object.
You need to convert your 2D organ into a 3D one, i.e. use tetrehedra instead of triangles. To do so:
- either you can use the component MeshTetraStuffing in SofaMisc (example here: examples/Components/misc/MeshTetraStuffing.scn)
- or you can use the CGAL plugin. The MeshGenerationFromPolyhedron allows to generate a tetrahedral mesh from a triangulated surface.
Hope this helps.
Hugo
Dear @Michel, dear @ceceyang,
I don’t have the same issue by compiling the v15.12.
I compiled it with Qt5 without any problem.
Let me know if the Qt drivers are the problem.Cheers,
Hugo
Alright, we’ll try to reproduce the error by compiling SOFA without image, Python and metis. We’ll let you know about the compilation outcome asap.
Cheers,
Hugo
Hi Cece,
As written in the output:
- metis isn’t compulsory, but it is needed if you want to compile the SparseLDLSolver,
- the image plugin is used inside the MeshGenerationFromImage component,
- and if you have no use of python scripting, then the plugin SofaPython isn’t needed neither.
However, the missing toolbar is strange.
Are you indeed using the v15.12 of SOFA (as specified) ?Cheers,
Hugo
Hi Zahra,
No problem for the delay, I just wanted to make sure you get the answer you need.
For what you are looking for, there is two ways:
- Link in the scene the “PointsDataFields” to the “force” data in the MechanicalObject of your object. The “force” data stores ALL accumulated forces applied on the body.
- Otherwise, create a specific data storing the forces in your own Forcefield. This data will thus be available in the scene and you will be able to link it in the scene with the “PointsDataFields”.
Let me know if you succeed in your simulation.
Best regards,Hugo
Dear Ash,
the RC1 version is now pretty old.
I would advise you to use the latest source version (and compile SOFA with Sensable) or the binaries of SOFA (and compile the plugin separately), which both are available on the download page. The plugin then should compile properly.Best regards,
Hugo
Dear Francesco,
Thank you for your interest in SOFA.
Let me answer to your questions about our framework.The models for deformable object available in SOFA are:
- mass-Spring Model,
- Finite Elements,
- linear finite elements,
- co-rotational finite elements,
- non-linar finite elements are also implemented but in private plugins. The access to these codes is therefore restricted but depending on your need, we can establish some partnerships,
In addition, you can find a wide range of boundary conditions, constraints in SOFA.
The main applications are :
- the medical applications (simulation of a specific organ, or a specific procedure)
- and the multi-physics applications (mechanics, thermodynamics, electrics..)
Finally, regarding the graphics library, we are using mainly OpenGL. However, I am no expert in this part of SOFA.
Do not hesitate to ask more, or read more on our website.
In the future, the community will be here to assist you with SOFA for your developments.
Could you tell us more about your own purpose using SOFA?
Hope this helps.Best regards,
Hugo
Hi Ash,
That was my next advice : using the binaries.
Good that you already did.
We are going to write some documentation about how to build a plugin when you’re using the binaries. Did you face any trouble on this step?Thank you for sharing and do not hesitate to ask any further questions.
Cheers,
Hugo
