I have simulated static meshes and a pawn with a static mesh that is simulated (the pawn is moved with forces). Both the simulated static meshes placed in the world and my pawn have constraints limited to a YZ plane (2D movement). This all works fine but as soon as any of these go into a physic field (chaos field) which simulates wind blowing in a direction, the constraints break. Suddenly, they can rotate and move on all axis.
Do you know what’s up? Thank you!
If I set the simulation > ‘default degrees of freedom’ in project settings to ‘YZ plane’, it does work but that’s not what I want to do as I will need to be able to rotate/move on all axis later.
Never mind. I ‘fixed’ this by removing REPLICATION of the pawn and it’s component. Not too sure why unfortunately.
Oh… I still have that issue actually 
It seems the issue is still there, because I have it too.
But in my situation it’s about two components connected with a physics constraint.
But, for me, if I keep the components moving, the constraint doesn’t break. It’s only when I stop moving them that it breaks.
So I actually found a way of fixing my situation: I put the sleep threshold to 0 on my component and it stops it from happening.
It seems in my case the constraint is broken when one of the connected components goes to sleep.
Hope this helps!