Wire Angular Spring Constraint
Constrains the rotation of a point on a wire object so it attempts to rotate naturally, but bounces back to its original rotation.
You need to create a 
Wire Object before you can use this tool. For example, this is can be used for an arrow hitting the ground.
Using Wire Angular Spring Constraint
Click the
Wire Angular Spring Constraint button on the Wires tab.Select the dynamic object or points to constrain and press Enter to confirm your selection.
Note
If you select the whole object, the constraint will be placed at the root of the object.
In this example, the yellow line illustrates the angular spring constraint which is attempting to return to the object’s original rotation.
For specific parameter help see the Wire Angular Spring Constraint node help.