Cloth Failures & Errors

[Adam Glazier]

I've set up a cloth sim and am experiencing 'ClothSolver Failures' and 'Self-Collision errors' that I can't fix no matter how much I tweak the 'Force Model' and 'Collisions' settings.

When my model is much more simple, the errors go away, but I need the level of detail that's there in order to accomplish what I need to do.

Are there any special settings to play with or a quick fix for 'ClothSolver Failures' and 'Self-Collision errors'? If not, is there another way to create a cloth like sim that can fold and bend with something other than cloth in Houdini?

Soft Bodies seem act similarly, but when the settings are soft to act more like cloth and I pull a point away from the object, that single point stretches out far without pulling the neighboring points like cloth does.

Any help with this would be great.

Edited December 9, 2007 by Adam Glazier

[Adam Glazier]

I still haven't figured out where all my errors are coming from, so I attached the file I'm working on. Hopefully it can glean some light on the specific errors I am having.

I'm running out of time to get this project done, so any insight into this problem would be greatly appreciated.

Thanks,

lense_tear_added.hipnc

[Adam Glazier]

The file consists of a dome attached to a ring (each made of cloth) both of which sit on top of a large sphere (static rbd) with the same diameter. The sphere is there so the dome and ring keep there general position and shape.

The dome also has a cut from the center to it's edge. The cut and the outer perimeter of the dome are stitched together with constraints that break when enough force is applied.

The ultimate effect is to use a moving constraint to peel away the dome. So it looks like thin tissue ripping from the cut and then the outer perimeter. The problems I am having is just getting it to exist without any of that animation.

In the DOP network you will notice two red DOP constraints. One of them moves and one does not. The one that moves is the test to see the dome being torn away from itself and the perimeter. When either of these are turned on, it causes even more problems.

[Adam Glazier]

After a lot of poking around, I have realized that Houdini's cloth DOPs can not handle complex sims. I am now looking into SyFlex and for the time being just going to hand animate the cloth.

In order to get a cloth like motion while hand animating points, I was advised to use this method.

1. Make keys points

2. Animation the points roughly.

3. Pull the points into CHOPs with the geometry CHOP

4. Add a spring CHOP

5. Use other CHOP filters if needed.

6. Pull points back into SOPs. Using channel SOP.

7. Skin surface.