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494 Chapter 12: Animation
this case, the end effector with the greatest weight
"wins."
Bind To Follow Object group
Controlstobindandunbindanobjectinan
inverse kinematic chain to a follow object.
(La bel)—Displaysthenameoftheselectedfollow
object. Displays the word "None" if no follow
object is set.
Bind—Bindsanobjectinaninversekinematic
chain to a follow object.
Unbind—Unbinds the selected object in a HD IK
chain from its follow object.
Pr ecedence (H D S olv er )
Make a selection with an HD IK Solver applied. > Hierarchy
panel > IK > Object Parameters rollout > Precedence
Youcanusethethreejointprecedencecontrolsto
alter how the IK Solution is calculated.
Thedefaultjointprecedenceis0.Thisissuitable
for many IK solutions. It assumes that joints
closest to where a force is applied (the end effector)
will move more than joints farther from the force.
Child->Parent—values are c a lculated by assuming
the root of the entire hierarchy has a precedence
value of 0 and each child has a value e qual to 10
times its depth from the root. In a four-object
hierarch y starting with the root, the val ues would
be 0, 10, 20, and 30.
Parent->Childvalues are c a lculated by assuming
the root of the entire hierarchy has a precedence
value of 0 and each child has a value e qual to 10
times its depth from the root. In a four-object
hierarchy starting with the root, the values would
be 0, -10, -20, and -30.
Default join t precedence occurs whenever all
joints in the kinematic chain have the same
precedence va lue. Assigning a value of 100 to
all objects in the kinematic chain is exactly the
same as assigning a value of 0.
An IK chain of three objects with precedence
values of 0, 30, and 200 would have the same
solutioniftheprecedencewerechangedtobe
1, 2, and 3.
Procedures
To assign a precedence value to an object manually:
1.
Select an object in an H D IK Chain.
2. Open the Object Parameters rollout in the
Hierarchy p anel.
3. Enter a value in the Precedence field.
To a ssi gn Child->Par ent precedence to a ll obj ects in
a k inematic chain:
1.
Select a l l objects in an HD IK chain.
2. Open the Object Parameters rollout in the
Hierarchy p anel.
3. Click Child>Parent.
To a ss ign Par ent ->Child precedence to a ll obj ects in
a k inematic chain:
1.
Select al l objects in the kinematic chain.
2. Open the Object Parameters rollout in the
Hierarchy p anel.
3. Click Parent->Child.
To r eset the def ault joint pr ecedence:
1.
Select al l objects in the kinematic chain.
2. Open the Object Parameters rollout in the
Hierarchy p anel.
3. Set the value in the Precedence field to 0.