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Animating with the HI IK Solver 429
Overlapping chains make the toe stick to the ground
Don’t try to overlap chains w ith different k inds of
IK solvers or you might get unpredictable results.
Creati ng Contr ol Objects
To create control objects to animate the goals,
create dummies, points, splines or other objects
near the goal, then link the goal to the control
object.Forexampleinahumanleg,youmight
have a goal at the ankle, ba ll of the foot, and the
toe. You then create three splines u nder the foot,
one for the heel, one for the ball and one for the
toe. Link each g oal to each spline, then you can
animatethegoalsusingthesesplines.Youcould
also link the splines together, s o that the rotation of
the toe is controlled by the movement of the heel.
Besides hierarchical linkage, you can now use the
new Constraint system in conjunction with IK
solvers. You could apply any of the constraints to
create a relationship between the goals or bones
and other objects. The goal could be position
constrained to a dummy which is moved. Or
you could create three bone chains that are all in
the same place, and constrain one bone chain to
another, then weight the constraints.
Bone chains constrained together
Using control objects gives you something bigger
toselectintheviewport.Youcanalsousecontrol
objects to separate chains, for example in a human
arm one chain could end at the wrist and another
separate chain be created for the hand and f ingers.
Thecontrolobjectatthewristservesastheroot
node for the hand chain, yet that chain would