Hi, I have a few vellum objects setup as balloons inside a room. I have them swirling around and moving kind of how I want, but when they hit the walls, they kind of just get pushed into them while the pop forces still move them around. I really want them to BOUNCE off the walls, floor and ceiling. I feel like I've tried everything, but just can't them to bounce off the walls. How do I do that.

The object is an .obj and the vellum solver is inside a dopnet.

any help would be appreciated.

I suggest turning off Friction with external collision objects (Vellum Solver DOP - Friction - External Enable) and disabling wind behavior for popaxis force (popaxisforce DOP - Behavior - Treat as Wind). They slow down objects by friction and wind resistance accordingly. Also, you can increase bend stiffness and decrease stretch stiffness to make your objects bouncier (ball like) but don't forget to increase the number of substeps in vellum solver to calculate the constraints properly. Another thing you can try to do is to tweak pop axis force to disable itself when an object is inside or outside a region (close to walls for example) or maybe to tie it with velocity somehow.

Faitel
I suggest turning off Friction with external collision objects (Vellum Solver DOP - Friction - External Enable) and disabling wind behavior for popaxis force (popaxisforce DOP - Behavior - Treat as Wind). They slow down objects by friction and wind resistance accordingly. Also, you can increase bend stiffness and decrease stretch stiffness to make your objects bouncier (ball like) but don't forget to increase the number of substeps in vellum solver to calculate the constraints properly. Another thing you can try to do is to tweak pop axis force to disable itself when an object is inside or outside a region (close to walls for example) or maybe to tie it with velocity somehow.

Nice! Thanks so much for those tips.