Hair particles on a moving and deforming mesh sequence

Support Particles and Physics Simulations
1

I have a .ply sequence of 10 frames (from a fluid simulation) imported with Stop-motion-OBJ which looks like this:
out_flow

The mesh is constantly having a change in the number of vertices/faces as it is deforming.

Now, I want the hair particles to behave as strands attached to these moving faces and follow the motion of the mesh. Something like this:
DNUjw

I did try a basic hair particle system and before that I did the following as well:

  1. Cleaned the imported mesh( removed doubles/recalculate normals)
  2. Created a particle system on frame 1
  3. Checked Use Modifier Stack
    I also turned the stiffness down to a super low value.
    Physics set to Newtonian and the rest pretty much the default.

This results in:
out_hair

I notice two problems immediately. First, the hair particles are still rigid and stiff and two, beyond frame #10, nothing happens except that they continue to remain stiff.

I am not sure what I am doing wrong or how to go about doing this as I am new to modeling particle systems in blender. Any pointers are appreciated.

2

Not sure what’s going on with the stiff hairs. You might ask this question on https://blender.stackexchange.com/

As for the second problem, how long is the .ply sequence you imported? Also, what Frame Mode did you select for the mesh sequence? If it’s set to Extend, then freezing the sequence on its last frame is expected behavior. Or were you referring to the hairs freezing?

3

I think that the particle system treats the mesh as a different objects in each layer rather than a single object that is deforming. I am not sure though. Yes, I was referring to the hairs freezing at the end of 10 frames as one would expect the hairs to fall down freely due to gravity as the mesh comes to rest and becomes stationary. I will post it on stackexchange.

4

I’m not sure I understand the full situation but if I do the problem might be your collision object. Some of my animations were running but my hair wasn’t moving. I finally went to my collision object & lowered the outer under soft body & cloth and got results. What nobody seems to tell us is the measurement units under the scene tab affects the numereric values in all the physics tabs. Make sure they’re set to real world settings. Gravity; z; -9.81 m/s & using imperial measurements the scale unit should be. 305 instead of 1. Hope this helps.