How to avoid intersection and unexpected movements?

Bongo
1

Hi,

the magenta object has a slider connection upward and is touching the grey object:

Screen Shot 03-15-21 at 02.06 PM
Screen Shot 03-15-21 at 02.06 PM1062×941 66.3 KB

After the physic simulation is calculated I see the magenta object falling down (intersecting the grey part) and side ward moving

Screen Shot 03-15-21 at 02.06 PM 001
Screen Shot 03-15-21 at 02.06 PM 0011062×941 65.5 KB

Is it a question of the setup to avoid this sideeffects?

-Micha

2

Hi Micha,

Thanks for you feedback, I’m happy to see you’re playing with these things. Both of these come from quirks in Bullet we’ve been trying to resolve for some time now. The first is a thing called margins, which is padding put around shapes that help keep the simulation stable. We try to offset the shape to hide them but as you can see it’s imperfect. The other is the connections tolerance with physics. They just aren’t as tight as the connections solver when not using physics. I haven’t found the right incantation of settings to make get them where they need to be yet.

It’d be super helpful to see the model though to confirm these are the issues, and try to resolve them.
https://www.rhino3d.com/upload?to=joshua@mcneel.com

Thanks,

Joshua

3

Hi Joshua,

I sent you an email with a download link. At this file you find this issue and an other.

Good luck.
Micha

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