[pierre]

Hi Hugo

Thanks, it works. I load a hexahedron gmsh mesh and specify the rest position coordinates in the scn file, then I use either a HexahedronFEMForceField or a TetrahedronFEMForceField.
Unfortunately I cannot figure out how to properly define a collision model for this deformable object. Whatever I tried has caused crashes so far. Is there a good example scene where the collision model is derived/mapped from a parent with hexahedral elements, maybe with some topological mapping in between ?
Best,
Pierre

[pierre]

Hi Hugo,

not exactly, sorry it was not clear. I am now considering a problem in one step only.
I would like to load the deformed shape only (volumetric mesh), and define a MeshSpringForceField which would be aware of all the rest edge lengths (those of the beam in its – straight – rest position). Initial forces would be derived from these initial displacements.
So I would not have to load this straight beam (whose connectivity is the same) but just its edge lengths.
I hope it is clearer now.

Pierre

[pierre]

Hi Hugo,

I’ve thought about an alternative process but I cannot find the appropriate method:
I would like to load the deformed beam as a mesh (obj), and define a MeshSpringForceField (or something similar) whose initial parameters represent the pre-stress. I guess this could be fully determined by the contraction/elongation values of each edge, which I know. What do you think ?

Pierre

[pierre]

Hi Hugo,
thanks
The deformation is actually such that none of these methods is actually a solution. I need to reconsider the whole problem I guess.

Pierre

[pierre]

Hi Hugo,

Thanks, that’s interesting. I think this could work, but unfortunately the QPL license of the plugin may become a problem at some point.
I am surprised there is no simple way to specify a constraint as a series of target positions for a subset of the input vertices. I find no example with FixedTranslationConstraint.

Best regards
Pierre

[pierre]

I guess the solution is in the use of FixedTranslationConstraint. I will try to follow this way.
Best,
Pierre

[pierre]

I like this two-step approach. I think it is suitable in my case, I just ignored one could specify a target deformation state defined by vertex-wise positions. Could you please provide a link to an example scn?
Best,
Pierre

[pierre]

Hi Hugo,

Thanks for your quick answer.
Yes you understood correctly: this is a pre-loaded beam. In my case the end configuration is actually not stress-free, but this beam will have to find its position into a rigid object (collisions included). But the real rest geometry of the beam is actually known, its is just straight, fully defined by some input obj mesh.
Best regards
Pierre

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