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tryhard_3d

Why does my RBD sim behave like this? [HELP] [Video Attached]

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Hey guys. So I'm working on this wall destruction sim in my spare time and this problem has been bugging me since last night! Firstly, I tried two ways to fracture the wall geo, Boolean and Voronoi. The boolean one worked fine but had a lot of issues with the geo post fracturing. There were a bunch of unshared edges and I could see the "planes" instead of the fully packed geo (Not sure why this is happening). The sim works find tho.

Anywho, I used the good ol' Voronoi fracture and its fine and dandy until I take it to the DOP network.
When the force impacts the wall, parts of the wall just disappears. I've tried to lower the force scale and it kinda fixes the problem but the force is too weak. So I then increase it and the same thing happens. (For eg at force scale of 50 it works fine but at 52 it doesn't (as shown in the video))

Disabling the speed limit works too but I can't get the look I want.

Can anyone tell me what the hell to do? I've been trying to figure it out for quite sometime now but just cant ugh.

Solver.png

SpeedLimit.png

Test.mp4

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Your force is so much that it can't solve it between one frame, increase your substeps and it will be fixed, as far as the boolean is concerned, make sure your geo is water tight and there is no unshared edges before you pass it to boolean also when you are booleaning make sure you have turned detriangulate to no polygons and uncheck the collapse tiny seam adjacent edges.

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23 hours ago, ronit1996 said:

Your force is so much that it can't solve it between one frame, increase your substeps and it will be fixed, as far as the boolean is concerned, make sure your geo is water tight and there is no unshared edges before you pass it to boolean also when you are booleaning make sure you have turned detriangulate to no polygons and uncheck the collapse tiny seam adjacent edges.

Ah alright cool thanks!
My geo is watertight. No unshared edges and stuff like that. Once  I boolean it, It gets messed up. 
I'll try the detriangulate option then. Does it retain the material attribute post fracture?
Anyway Thanks!

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This happened to me from time to time, which was mostly because Houdini didn't like something about the model.

What often worked for me was to either put a boolean and use Union for the Operation and put your geo to both the left and the right inputs. Or put a divide SOP which I think is the same as triangulating or remove the convex polygons option and use bricker polygons.

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20 hours ago, tryhard_3d said:

Ah alright cool thanks!
My geo is watertight. No unshared edges and stuff like that. Once  I boolean it, It gets messed up. 
I'll try the detriangulate option then. Does it retain the material attribute post fracture?
Anyway Thanks!

yes it does retain every attribute, it shouldn't be a problem

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