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1080 Chapter 14: character studio
Using Physique with 3ds M ax
Bones
3dsMaxboneswithorwithouttheIKController
canbeusedwiththebipedforvariouseffects.
They can b e used with Physique to add extra
linksandenvelopesforanycharacter,orto
animate assemblies on a robot or mechanical
character. B ones can als o be added to animate
extraappendages,ahat,ajawandsoon.
Note: If 3ds Max bones using the IK Controller are
linked to the biped, the Auto Key button must be
left on while the biped is positioned.
Two examples of compressible bones.
In the top image, 3ds Max bones are used to
animate the linked piston assemblies. The bottom
image shows 3ds Max bones used for added
control when Ph ysique is applied. In both cases
the bones compress automatically as the biped is
positioned.
B ones T hat Compress
Onewaytouseboneswiththebipedisto
use the Select and Link tool on the 3ds Max toolbar
to link the root of the bone to one part of the biped
andhavetheboneEndEffectorfollowanother
part of the biped. As the biped moves these b ones
compress and expand.
In the image of the mechanical leg, piston objects
arelinkedtothebones. Asthebonescompress
and expand, they also animate the linked piston
assembly. Asthebonescompressandexpand
in the abdominal area in the bottom image, the
envelopes created by Physique for the bones
compress and expand to animate this area on the
mesh.
IK Solution
In the IK Controller Parameters rollout, you
specify the accuracy of the IK solution and the
frame duration of the solution. For bones that
compress, you generally want an accurate solution
to ensure that the bone follows the end effector
perfectly, without any drift. In the image of the
rollout Position has a value of 0, the least amount
of allowable distance (Rotation is at its default
value of 1, the Rotation End Effector is not used in
this example). Iterations is set high , ensuring that
that the solution is accurate, even if the character
is scaled down a g reat deal. Start and End Time
should span the animation.