Physics and bone simulation

Hi, tell me, how can I make sure that parts of my mesh don’t fly across the screen when they fall, but are connected (like in this file )?

I see that there are dummies at the top of the stage and they just set the maximum distance between body parts at any time during the simulation. However, I do not understand how this mechanism works. Can someone explain this to me or give links to textbooks?

Any help? Does anyone really understand what this is about?