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Hello @hugo,
I tried to use TriangularTensorMassForceField to model a deformable vessel and use RestShapeSpringsForceField to fix both ends.
However, when I used instrument to drag the vessel, the parts closed to both fixed ends would expand distrotedly, which was not like the normal behavior of the relastic one.
You can get the .scn file by this link:
https://www.dropbox.com/s/5vncrc7vdf9o6lo/TriangularTensorMassForceField.zip?dl=0
Is the configuration is wrong or any other triangle force field can be used to model deformable vessel?
Wong
Hello @rainvector
I do not think only BeamFEMForcefield is sufficient. Because using rigid dofs with BeamFEMForceField can only make surface mesh deform globally but not locally.
You can try to construct your example scn and test if it is true.
Wong
Hello @hugo
I have ever thought about rigid dofs mapped from vec dofs with TetrahedralCorotationalFEMForceField. But I do not think the tetrahedral elements are suitable for a tubular model. The size of the element would be small and the number of the elements would be very large so it would lead to high overhead and low frame rate.
So I think a new force field component is needed to solve this issue.
Is that right? Or you can give your own example to implement it?Wong
Hello @nickhockings,
Although I built it successfully but actually I want to report that there were some compile errors which occured in VS2015.
like in load_surface_meshes.cpp line 35
YAML::Node config = YAML::LoadFile(it->c_str());
should be change into
YAML::Node config = YAML::LoadFile(it->string());And there are some other places using c_str() too.
More, movable_sphere2.scad cannot be found in directory test_mesh_generator.
Wong
Hello @hugo,
luckily, I tried to buid it and I succeeded! Only CGAL and Yaml-CPP should be built threre, other dependencies can be directly downloaded and used.
I would continue to test it if there are bugs there. But I think it is hard for me to read the code about CGAL and there is very few information and tutorials on the Internet about how to code with cgal. So it would be better if some instructions about CGAL programming are provided.
Wong
Hello
I think you can take a look at this link to see if it is suitable for you.
Hello @hugo,
Can you tell me how to use MeshMatrixMass because there is no existing example.
I use RestShapeSpringsForceField because I do not want to make the fixed part so hard sometimes.
Wong
Hello @hugo,
Just want to drag or block the artery/vessels and clip the aneurysm. So the level of accuracy should be fairly high.
Wong
Hello @hugo,
Just deform flexibly like the real one, from all directions and keep the performance in persisting contact. Because the vessels are located in the gap of the soft tissues.
Wong
Hello @yordan-kyosev
I think the situation is more complicated than you think. What I want to model is something like vessels. So you have to think on the case that the rope has branches.
As far as I can see, representation of beam is still nothing more than a strings of rigid bodies. It may cause low performance having masses of rigid frames and it can never deform radially when it is being clipped.
And I cannot buy your book in my country as well.
But I am still interested in your work and I still want you to provide more information if it is still possible to help.Thanks,
WongHello @epernod
By the way, now how are your TopologicalModifiers coming along in volumetric cutting? I think the topological change for tetra mesh at runtime could help deal with this problem.
Wong
Hello @epernod
Well, I have to say that I have ever tried to use SubsetTopology.
But the first problem is that using SubsetTopology would make the scene more complicated and inefficient. Secondly, the spring connecting the Hex and Tet mesh would result in abnormal behavior when the haptic feedback involves. And the constraint solving process would be time-consuming. Or you can provide an example to prove that this way is viable?I also have looked for relevant information about CGAL to solve the problem. But coding for CGAL is very complicated and there are too little examples. Can you tell me how to put seeds using CGAL?
Wong
Hello @hugo
Do you mean you will talk about this case in the session?
After all I will be not be able to attend this session and I do not know if you will find a solution at last.
So I think I will try another method to solve this issue, such as remeshing techniques and will also at the same time wait your news after the session.Wong
Hello @hugo
I did not couple the needle and the brain though. You saw such scene at the beginning just because the Geomagic plugin was not at work.
Well, what I want to achieve is to make the local deformation closer to reality as you can see in the picture of the realistic surgery in the attachment.
Did you see the two pictures in that attachment?
Wong
Hello @hugo
ROIBarycentricMapping does inherit from BarycentricMapping.
You can see the m_mapper there.
Wong
Hello @Hugo,
I use Sofa v19.06 and there is no any compile error.
And can you tell me how to make it an external plugin?Wong
