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ParticleSkull

FLIP particles disappearing! one by one...

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I'm a bit new to Houdini so it might be something simple.
 
The scene have only the "cup" (a modified Tube) and the FLIP trying to fall inside the cup.
 
I've unchecked the "Use Volume Based Collision Detection" on the cup, it's a static solver. Despite of that everything is on default settings.
 
Could the Volume Based Collision be the solution? I couldn't create an accurate collision shape with this option on.

 
Thank's,
 
Alvaro

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yes, you need volume based collisions for FLIP as it needs to do pressure projection on volumes for which it requires  collision SDF

Deforming Object Shelf Tool from RBD Shelf should give you a good starting point

Edited by anim
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Check the attached image. Turn that option on. It shows the collision sdf volume. I am sure the volume is not correct.

 

 

Cheers!

post-7403-0-52359600-1459762344_thumb.jp

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make sure you check for holes in the geometry, i advice you to place a polycap before plugging it anywhere further, this should help you.

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Thx guys,

Tomas, thx for the technically accurate reply. It's great to understand why it's why not working. I couldn't find the SDF

Deforming Object Shelf Tool though but i'll keep loking for something about it on google.

 

Ranadeep, thx! I just can't make this volume look good, check it out. Maybe that's because it's concave?

flip%20problem_zpsoslavey8.jpg
 

Naveneet, thx but i'm pretty sure the geometry don't have holes. it's pretty simple and it's all fused. I've added a polycap but it closed the the top of the cup, where the liquid should fill in.

Thx,
Alvaro

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You need thicker walls on your collision object, like 10x as thick to start with, and the bottom too.

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Hey Kleer, i've just scaled everything up to 10x and still gettin' similar results.

Is there another way to generate this collision object? Maybe something related to the "collision SDF

Deforming Object Shelf Tool" Tomas' said? Couldn't find anything about it around.

Thx

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...Maybe something related to the "collision SDF

Deforming Object Shelf Tool" Tomas' said? Couldn't find anything about it around.

..

the new line was actually start of new sentence, the name is only Deforming Object Shelf Tool

and you can find it in Rigid Bodies Shelf, third tool from left

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Sorry guys, I know it might be simple but my lack of knowledge is huge.

Tomas, thx and now I found it but it doesn't work at all. I couldn't create any collision area with the "Use Volume Collsiion Detection" on.

The file is here in case anyone could have a look at it ;)
https://onedrive.live.com/redir?resid=7E0749DA4721B06!27242&authkey=!AD2XTVGKKnslq-8&ithint=file%2crar


Cheers,
Alvaro

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Alvaro, it looks like you forgot to check 'output back' in your PolyExtrude node, so your tube has no inner faces. :)

 

--Dave

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:blush:  damn, you're right Dave. now it's working perfectly!

Thank you for all the info guys, despite of the ridiculously obvious mistake i've learned some great stuff on this thread ;)

/Alvaro

 

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i also gone through same problem some times ago............

 

some points you need to check it

1. make sure your scene scale is proper.

2. make sure your interior doesn`t have any holes in that.

3.if you have thick object. make sure turn it into vdb from polygons and check fill interiors. 

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Thx Tushar, i'll remember that.

 

Dave, about this last example. Have you just added a vdb from polygons to the setup and made it a Static Object? (edit:) Have you setted up anything else to make the vdb collide properly? I've tried to recreate what you did but it's not working properly. it looks like theres holes on the mesh

Edited by ParticleSkull

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some points you need to check it

1. make sure your scene scale is proper.

2. make sure your interior doesn`t have any holes in that.

3.if you have thick object. make sure turn it into vdb from polygons and check fill interiors. 

Tushar, what would you consider a proper scale?

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