The wire stretched out very long,how to control it!Help! PLS!!!

[SpeedASS]

I constrain rigidBodyA and rigidBodyB by 6DofSpring2 Constrant,even though the LinerLimit is very small(0 or 0.01),there always get the issue that the wire between rigidBodyA and the rigidBodyB are stretched out very long if i move the A or B very quickly, how to control it？
I have tried to change the EPR value,and the solver iterator. The change of solver iterator's times only makes a little scence,but not enough.what should i do？ I have fall in trouble with this for a long time, i really want to solve the terrible Stetch.If someone can help me，Please

[drleviathan]

To summarize your problem (and correct me if I'm wrong): you have a spring constraint that is not stiff enough for your purposes.

Weak springs are easy and stiff springs are hard (they can go unstable). Here's some advice without knowing more about what you're really trying to do:

(1) Maybe you want to use a point2point or fixed constraint? They are stiffer but not springy.
(2) If you really need a spring: try reducing your substep if possible (1/240s and smaller but probably not lower than 1/1000s).
(3) If those solutions still don't work... then your needs are special and you will have to supply a custom solution, like an Action with a manual verlet integration step which helps your pair of objects stay together.