Pin Attach Constraint RBD object

[RomanoWina]

Hi,

I am looking for a way to make the top of cup/Bucket interact/collide with a fluid mesh so that the fluid will lift the lid of the cup when it comes out without sending it in the air, it will remain attached on the x axis.
i was thinking of using a RBD Pin Constraint  (but it doesn't work) or using a bone on a static object using the deforming geo so the top will rotate only on the Z axis. What would be best?

Thanks for your advices,

 

Romano

Bucket.hipnc

[nuki]

I would use a hard constraint with type set to ''position'' for the hinge.
For simple one-way collision with the fluid I'd mesh the fluid, convert that to vdb and get a collider for bullet with vdbtospheres.

eg. like in the attached file

it would probably be a good idea to match the flip solver substeps to the bullet substeps.

constd.hipnc

Edited February 25, 2020 by nuki

[Noobini]

wooo Effin' hoo...took me aaaaages to get this going with RBDsolver SOP (obviously not actual liquid)

 

[nuki]

hm, if i use my exact same setup, just with bullet sops, the whole thing gets unstable af. Raising constraint substeps helps a lot, but I cant get completely rid of the jittering.

constd2.hiplc

Edited February 27, 2020 by nuki

[nuki]

ah, its the constraint force mixing - which is enabled by default for hard constraints on the solver.

[RomanoWina]

Thanks a lot for your tips 
Cheers