How to control one object with two pivot points I am trying to parent two empties to control the extremity of the object as pivot point

as you can see it works fine for the first one
(the object and the other pivot point are affected, which is what I want)

But I can't parent back the right empty to the left empty (error message &quot;parent loop&quot;)

Any idea how to achieve this kind of empty controller?
(left empty control relatively to it's position, the rotation of the part and the position/rotation of the right empty. Right empty control, relatively to it's position, the rotation of the part and the position/rotation of the left empty)?
One way is to use Active element as pivot point.

Parent both empties to your object
Set Pivot point &gt; Active element
Select your object and then the empty you want to pivot around