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426 Chapter 12: Animation
of the two nodes. If you are using an IK Limb
Solver, the IK goal will be placed two bones
down from the highest node you’ve selected in
the chain.
Where to Adjust the I K Solver
You adjust IK solver settings in the Motion and
Hierarchy panels:
•
Motion panel (page 3–817)
When the goal of an IK chain is selected, the
motion panel displays the rollouts for the
individual IK solver.
HI S olver —Motion panel parameters adjust the
swivel angle (page 2–430) of the solver plane, to
point the knees and elbows. Also, the controls
in the IK Solver rollout let you mix periods of
IK w ith FK (forward kinematics) through the
Enabled button and the IK button.
HD Sol ver—Motion panel parameters assig n,
remove, and edit the end effector for the
currently selected joint. You can parent the
end effector to another object, and return
the skeleton to an initial pose. Changing IK
controller parameters in the Motion panel
affects the entire HD IK chain, even when
you’ve selected only a single bone.
IK Limb S olver—Motion panel p ar ameters for
the IK Limb solver a re the same as for the HI
Solver.
Spline IK Solver—Motion panel parameters
allow you to activate/deactivate the solver,
adjust the bones assigned to the start and end
joints, adjust start and end twist angles and
make twist handle display settings.
•
Hierarchy p anel (page 3–816)
HI Sol ver—When a bone is selected, the IK
panel displays controls to activate and limit the
rotational joints, and set a preferred angle for
thejoints.Thepreferred-angleposesofallthe
joints help control the direction of rotation of
the l imbs. When a goal is selected, the IK panel
is blank.
HD Solv er—Select the end effector of an HD IK
chain. In the Hierarchy panel, click IK. The
controls that appear affect the HD Solver. You
will also find the tools to bind to follow objects,
and set precedence and joint limits, damping
and spring back.
IK Limb Solver—When a bone is selected, the IK
panel displays controls to activate and limit the
rotational joints, and set a preferred angle for
the joints. The preferred-angle poses of all the
joints help control the direction of rotation of
the l imbs. When a goal is selected, the IK panel
is blank. If you select a bone before applying
an IK Solver, a different set of sliding and
rotational joint par ameters w il l be displayed,
but these w i ll b e replaced once an IK Solver is
applied.
Spline IK Solver—SelectthesplineofanSpline
IK chain. In the Hierarchy panel, click IK. The
controlsthatappearaffecttheSplineIKSolver.
Youwillalsofindthetoolstobindtofollow
objects, and set precedence and joint limits,
damping and spring back. T he controls in the
IK panel are similar to the HD Solver.
Procedures
To add an IK solver to a hierarchy or bones system:
1.
Create a bones system or any other linked
hierarchy of objects.
2. Selectaboneoranobjectwhereyou’dlikethe
IK chain to start.
3. Choose Animation menu > IK Solver, and
choose the IK solver:
• HI Solver for character animation
• HD Solver for mechanical assemblages w ith
sliding joints
•IKLimbSolverfortwo-bonechains