Illustrator :: Lock The Centre Point Of An Object?

I'm using illustrator (CS6) to animate a simple marionette type figure.
 
I'm using the Rotation tool to turn body parts around their usual connection points, moving the transform centre point each time.  I'm wondering if it's possible to "lock" the centre point for any individual object to a certain offset from the object's actual centre, so that every time I reselect an object to move it I'm always rotating it around exactly the same place.  I find that if I have to move the centre point from the real centre to where I want to rotate around every time, I'm not getting the exact same spot in relation to the object's bounds, which makes for some weird movements.
 
For example, the rectangle that makes up the upper arm should have its rotation point always about ten pixels down from the top and in the horizontal centre of the object.   The elbow right at the top edge, but also in the horizontal centre, of the lower arm.  etc.