Hi, everyone.
I tried to make a breakable object on the ground but it didn't work well.
I did following steps.

1. made a box on the origin.
2. set the center of it to the half of height to sit exactly on the ground.
3. made it RDB and did “Make Breakable”.
4. made a ground plain on the origin.
5. run simulation.

Then, the box exploded at 2nd or 3rd frame:-(
Why? I just want to put a breakable object on the ground…

I attached a sample file to share my problem.

OS: Mac OSX 10.7.2
Software: Houdini 12.0 Apprentice

Thank you.

Working fine on Houdini 12 / 11 on Windows.

sadhu
Working fine on Houdini 12 / 11 on Windows.

Hmm.. I think this kind of phenomenon is not OS sensitive.
Anyway, thank you for replying!

I tried with Houdini11 and it works fine.
Something changed in Houdini12 may do bad.
I will use Houdini11 for a while.

The problem is solved.
If the solver engine in rigidbodysolver node is Bullet, the problem occurs.
The other solvers works fine.
If you want to use Bullet, make higher “Number of Substeps”.
In my case, lower than 11 at this param causes the problem and higher does't.

When using the bullet solver and fracturing try to avoid concave polygons, bullet is quite sensitive.

rob

circusmonkey
When using the bullet solver and fracturing try to avoid concave polygons, bullet is quite sensitive.

rob

thank you!
I used bullet engine without understanding it.
I will learn more!