Now that you have that extra group for each of your controls, centre the pivot for each one. This pivot should be in the same spot as the pivot of the child control.

Grab each SDK group (easiest to do in the Outliner) and group that node to itself again, and centre the pivots. This group will be used for parenting all of the lip controls to the characters skeleton, specifically the jaw and/ or head.

Fig 10. The Animation Controls

Fig 11. Connections in the Hypergraph

Rename each one with the same control name plus the suffix "_group". Don't worry; this is the last grouping you have to do on the controls. You should now have three levels in the hierarchy for each control object. Now we need to create a relationship between these controls and the joint chains made for the lips.

First we'll tackle the top level of the control hierarchy, which is the "_group" node. This node will be driven by the jaw transforms through the use of parent constraints.

Grab the Mouth_top bone, then the Mouth_Bottom bone, then one of the "_group" control nodes.

Open up the Parent Constraint Options Box and make sure maintain offset is turned ON. Now apply it.

If you grab the jaw and rotate it, you'll notice that the "_group" control that you just constrained will partially follow along. This is the magic of parent constraints. Parent constraints are our friends. (If you remember ever having to set up point constraints for two objects to control a third and then animate the weighting between the two, you will grow to love the parent constraint with the white hot passion of a thousand suns going nova, as I do.) If you fiddle with the W0/W1 attributes in the channel box, you'll notice that the control will be more influenced by one parent or the other. Let's establish an inverse relationship between the two so that when one goes up, the other goes down, and they both total one. How? Simple as pie through the Hypergraph.

Open up the Hypergraph and Graph the inputs and outputs of one of your control groups.