Case (946765) [beta 9] Problem with rigid bodies

I have a problem that has shown up over the last few betas. When you have a GameObject instantiate another GameObject and make it a child of the first GameObject. If the child GameObject has a RigidBody, and if you move and rotate the parent object, the child GameObject doesn't track right with it's parents GameObject.

I filed a bug report under Case (946765)

 

Is it kinematic?

 

It seems to happen if the child is kinematic, or dynamic. If the child is dynamic then the weird flipping movement happens for all children. But for kinematic children this behavior only happens if you instantiate the child at run time.

 

In the bug report I created an example project that displays the buggy movement. Here are some screenshots of it.
The child Rigidbody starts flipping away from its parent Rigidbody.

 

Child rigidbodies behave independently. That is, they should never move with the parent. If they should move with the parent, they need to have a joint to link them.

If they were moving before in this scenario, then they would have been incorrect.

Your screenshots are meaningless, btw. Please upload a video at least.

 

Well the behavior of how the child rigidbodies move has changed with the last few betas. Also I have a game that I have been working on for 6 months, with previous versions of unity, and this bug has only shown up in the last few betas. I only included the screenshots to kind of show what was going on. I have already made a bug report, and I made an example project to show what the bug is.

 

The bug is still happening in beta 10, and no one has even looked at the bug report yet. Here is a video that I made that shows the buggy behavior.

Also I'm thinking that the cause of the bug might be when I rotate the rigidbody by 180 degrees. But the way that the rigidbody is flipping around is very buggy. And this behavior only started in the last few betas.