Issue with Softbody Simulation for Vascular Modeling

[W_chack]

Hi,

Using particles to simulate a mesh like this one is not a good idea at all. The reason is that ellipsoids are a terrible at approximating thin, long shapes, which this mesh is almost exclusively made of. For modeling vascular systems, cosserat rods are a much better approach, and tetrahedral meshes can do a good job too.

If you really want to use a particle-based engine for this, I'd suggest:

- Drop voxel sampling entirely. You'd require extremely small voxels to pick up such thin features.

- Subdivide your mesh such that edge loops (and hence, vertices) are evenly distributed throughout its surface, then use vertex sampling instead (that is, set "Surface sampling" mode to "Vertices" instead of "Voxels")



The reason why adding longer vessels seemingly reduces the amount of particles used is because the bounding box becomes larger, and since your voxel resolution (which determines the amount of voxels used for the longest axis of the bounding box) is kept fixed, the amount of voxels used to sample the mesh is the same which means larger voxels must be used. Note you can enable "Voxels" in the Render modes tab at the bottom of the blueprint editor to visualize voxelization.

All these issues can be worked around by using vertex sampling instead of voxel sampling, as mentioned above. Still, ellipsoidal particles can only do so much when faced with such thin and long structures.

kind regards,

Thanks for your prompt and detailed response. I will try based on your suggestions.
With appreciation!