Animated fracture oddity on object bind

[gldr327]

hello everyone,

I'm having an issue that I having a problem identifying the cause and was hoping to get some other eyes on it.(High likelihood this is something very simple that my own inexperience is causing.) I've tried to simplify everything to the most base components and the problem is still happening.

What I'm looking to do is have an animated sphere collide with another animated square and blow a hole through it. I can get everything working and looking great in high rez except for one part. At the moment of the actual collision (frame 237), the fractured particles shift in front of the animation for one frame before velocity and forces make them fall away as they should.

I've been spinning my wheels on this for days so any suggestions would be greatly appreciated.

[d4rk3lf]

It probably has to do with time-step.

You see.... your objects are moving very fast, and when PhysX try to solve it, if it's going frame by frame... that way, it might even skip some of the collisions (simply because it's sees objects that are not colliding in one frame, and in the next frame they are also not colliding (because objects were so fast, an d already passed the object that are meant to collide with).
The solution for this, is to just grab Tyflow icon, and decrease time-step option from frame to something lower (1/2, 1/4... in your file I have gone to 1/12 until I saw that is looking correctly).
1/2 means that it will divide frame to 2, and it will guess motion of objects (by splitting the time to half)
1/4 means same, but 4 times.. and so on...

The lower you go, the slower the sim will be, but more precise.

There is also additional options for this under the PhysX rollout, for more precise adjustments,

[gldr327]

Instant and beautiful success!! Can't thank you enough d4rk3lf thank you not only for the solution but the explanation of why, greatly appreciate the lesson, applied it to a couple of other flows I've been working on and it improved the results!ank  j