8

802 Chapter 14: Character Studio
5. Reselect the biped COM either by selecting the
blue octahedron near the center of the biped’s
pelvis, or by clicking one of the three COM
track controls.
Lock COM Keying restores the selected
controls.
Inter face
Body Track Tools (Center of Mass Tracks)
Body Horizontal and Body Ver tical refer to the
center of mass’s translation axes while Body
Rotation focuses on its rotate axes. Once you
turn them on, you can move or rotat e the COM
by either using the Transform gizmo, by entering
values in the
Coordinate Display area (page
3–755)
.
Tip: You can also set COM positions using the
Tension, Continuity and Bias values on the
Key
Info rollout (page 2–809)
(in the TCB group).
When you activate Body Horizontal or Body
Vertical, you have access to advanced
Biped
Dynamics parameters (page 3–1010)
,suchas
Balance Factor (page 3–1008) and Ballistic Tension
(page 3–1008)
, which you can control from the
Key Info rollout (page 2–809) and Dynamics &
Adaptation rollout (page 2–833)
.
Note: Tension, Continuity, and Bias affe ct the
COMBodyVerticalkeysonlywhenthevalueof
Dynamics Blend (page 3–1025) is less than 1.0. To
turn gravity off at a vert ical center of mass key, set
the value of Dynamics Blend to 0.0.
Tip: To view the way a parameter change affects the
animation, Tu rn on
Tr ajectories (page 3–1119) .
KeyedkeysforCOMtracksarecolorcoded
as follows:
• Keys containing Body Horizontal tracks are red.
• KeyscontainingBodyVerticalareyellow.
• Keys containing Body Rotation are g reen.
Note: If a frame contains multiple keyed
COM tracks, the k ey’s color code is divided
accordingly.
A key’s color reflects its keyed COM tracks.
Body Horizontal—Selects the center of mass
to edit horizontal biped motion.
The Body Horizontal track has a
Balance Factor
(page 2–735)
parameter that automatically orients
the biped to maintain balance. This saves the
animator from having to reposition the pelvis
when the biped leans forward, backwards, or
sideways.
Note: Biped D ynamics (page 3–1010) parameters
can b e animated from no effect to full effect at
each keyframe.
Body Vertical—Selects the center of mass to
edit vertical biped motion.
The Body Vert ical tr ack uses the Dynamics
Blend parameter to control gravity in a footstep
animation. A Dynamics Blend value of 1.0 uses the
value of
GravAccel (page 3–1044) (global gravity
value) to calculate an airborne trajectory for the
biped. No keyframes are required to position
the bip ed in the air, a trajectory is calculated
automatically. A value of 0.0 uses Spline Dynamics
for the vertical position of the biped; you must
create keyframes to position the biped vertically.
The Body Vert ical track also has a
Ballistic Tension
(page 3–1008)
parameter that controls how much
the biped k nees b end w hen the biped lands from