Want Driver bone to follow rotation of what its controlling

Here’s what I have:http://youtu.be/KVZohpsTzEU

To explain it better, I want the bone (wire frame box around what it’s controlling) to stay around the box its controlling location and rotation-wise. so it’s basically the box except wire frame and its moving exactly with the same way. This is just an ease for access type rig so I don’t have to go in and edit the drivers manually.

Cant you just make the target box a sphere?

If you really want to keep it a wire box, give us more information on your setup. Is ToneArm rigged with bone? Or, are you using other method?

That would be called a circular dependency. Object A moves Object B which moves Object A which now has to move Object B again? It’s not logical. If it’s controlling the location of its dependent, it should be around it at all times anyway. You have something else going on that is separating them, or it’s not really controlling the location.

What you want, my friend, is a custom shape for the bone that shows as a box around the cartridge (needle housing). The actual bone would run along the tonearm and its pivot point would be at the pivot of the tonearm. You don’t need a driver, so why go to the trouble? a tonearm only has two axes of rotation and NO translation. Perfect for a single bone setup.

If on the Controlling object you set the ‘Location’ of the Rotation Axis at the same ‘Location’ of the Rotation Axis for the Needle Bar… then use only use ‘Rotation’ and not Translation to Animate the Controller… all should be good… (This is using Objects and not Bones)…
But then if you did that…
I would be wondering why I would need the Controller Object in the first place… why not just Grab the Needle Bar and Rotate it around to where it needs to be…