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Setting Joint Precedence (HD Solver) 449
movement when you t ry to s queeze it against
your upper arm or extend it all the way out. Ease
simulatesthiseffect.
Dampi ng Joint Action
As a joint corrodes, dries out, or is put under a
heavy load, it resists motion along its active axes.
Damping simulates the natural effect of joint
friction or inertia. Enter a value greater than zero
in the Damping field to apply resistance over a
joint’s full range of motion.
As damping increases a joint resists motion and
other joints are required to move more. A damping
valueof1.0meansthereisextremeresistanceand
ajointwillnotmoveonthataxis.
For example, a telescope with no damping a t all
allows each c y linder to move to its maximum limit
before the next c ylinder moves. If the cylinders
havedampingvaluesassigned,theneachcylinder
causes its parent to begin moving b efore it reaches
full extension.
Setting a Joint to S pr ing B a ck
When a joint resists motion, it also has a tendency
to return toward its at-rest position. You simulate
this by setting Spring Back tension in the joints. As
the joint moves f urther from its rest position, an
increasingly larger force pulls the joint back, like
aspring.
When you set Spri ng Tension higher, the spring
pullsharderasthejointmovesfartherawayfrom
its rest position. Very high settings can turn the
joint into a limit, because you can reach the p oint
wherethespringistoostrongtoallowthejointto
move any farther.
S etti ng J oint Precedence (HD
Solver)
You set Joint Precedence to control the order
in which joint calculations are applied to the
kinematicchain. WhenanIKsolutionis
calculated, the result is dependent on the order of
calculation for each joint.
The hoof (a child) has precedence over the leg (its parent).
Foranygivenpositionofanendeffector,thereare
many possible IK solutions.
ThethreejointprecedencecontrolsintheObject
Parameters rollout are: