9

Sliding a nd Ro tational Joints (HI Solver) 459
Goal Display group
ControlstheappearanceofthegoalsintheIK
chain. On by default.
Enabled—Turns the goals display on or off.
Size—Controlsthesizeofthegoalgizmointhe
viewport.
Swivel Angle Manipulator group
Controls the display of the swivel angle
manipulator in the IK chain. Default = on. Turn
thison,thenturnonManipulatemodetoseethe
swivel angle manipulator.
Enabled—Turns the swivel angle manipulators on
or off.
Size—Controlsthesizeofthemanipulator’shandle
in viewports.
Lengt h—Controls the length of the manipulator
in viewports.
IK Solver Display group
Controls the appearance of the IK Solver display,
the line drawn between the start and end joints.
Turn this on whe n you have mu lt iple ch ain s t hat
you want to see at the same time.
Enabled—TurnsonorofftheIKSolverdisplay.
Sliding and Rotational Joints (HI
Solver)
Create a bone chain. > Apply an HI Solver > Select any
bone in the chain. > Open the Hierarchy panel. > IK
button
Here are the controls for setting the joint limits
when us ing the HI Solver. You c an turn X, Y, or Z
axes on or off, limit them, and set those limits here.
This is also where the preferred angle is defined,
and adjusted. The preferred ang le defines the
direction a chain will bend, which angle a chain
will tend to rotate toward.
Note: SlidingjointsareimplementedintheHI
Solver,buttheydonottakepartinanIKsolution.
They do, however, take par t during FK interactive
manipulation.
Use the HD Solver if you need to animate sliding
joints with inverse kinematics.
Procedures
Example: To set the direction an IK chain will bend
(prefer r ed a ngle):
To understand setting the preferred angle it helps
to use a simple example.
1. Go to Create panel > Systems and turn on
Bones.
2. TurnonAssigntoChildrenandmakesurethe
HI Solver is displayed in the Solver name field.
3. IntheTopviewport,createabonechainoffour
bones in a straight line .
4. Turn on the Auto Key button, and move the
time slider to frame 50.
5. Selectandmovethegoalsoitisclosetothe
root node.
6. Select any bone in the chain.
7. On the Hierarchy panel > IK panel, open the
Rotational Joint rollout.
8. Therearethreeaxes. Findtheonewiththe
preferred angle that is not zero.
9. Change the preferred angle. If it is negative
mak e it a positive one.
10. Play the anim ation, see how changing the
preferred ang le can redefine the direction of
the rotation.
To set r otational j oint limits on a hierarchy of objects
or a bo ne chai n:
1.
Createabonechainorahierarchyofobjects.