In this lesson, you completed
the animation of a mechanical arm model that picked up and moved
a cargo box. You learned how to:
- Construct a model hierarchy to provide
relationships between the components for posing and keyframing.
- Construct a single chain skeleton to
pose the arm model using Inverse Kinematics.
It is common to create
characters with multiple joint chains. For example, two and four-legged
characters would use multiple joint chain skeletons to assist with
posing their hierarchical structure. See
Skeleton hierarchy in the Maya
Help. For a tutorial on creating a multiple chain skeleton
see Lesson 1: Skeletons and Kinematics (
- Parent the components of the mechanical
arm model into the skeleton hierarchy.
Parenting is one method
for combining a model into a skeleton hierarchy. When using characters
that have bending or deforming features a more common technique
is to use Skin > Bind Skin. For more
Skeletons and skinning in
the Maya Help. For a tutorial on
smooth skinning see Lesson 2: Smooth Skinning (
An easy method to parent
one node to another using the Hypergraph is to
drag one node over top of the other using your middle mouse button.
- Create an IK system with a control object
It is very common to
create characters with multiple joint chains and multiple IK handles
to control them. Control objects simplify the selection and posing
of the character.
- Use three types of constraints (Point, Orient, Parent)
to control components of the IK system and other components in the
Constraints are useful
for animating the attributes of one object based on the attributes
of another. Other types of constraints not covered in this lesson
include aim and scale constraints. See
Aim constraints and
Scale constraints in
the Maya Help.
Using the parent constraint,
the platform could also be animated to move the cargo box as if
it were on an elevator, or a conveyor belt.
- Apply limits to the movement of the IK
In this lesson, you constrained
the translation of the control object in order to constrain the
movement of the IK. It is not recommended that you set limits on
the rotation of an IK system as it limits how the solver calculates
the position of the joints. See
Setting up joints for posing and animation in
the Maya Help.
Although not covered
in this lesson, it is possible to simplify the display of attributes
in the Channel Box so that only the
animatable attributes associated with a character are displayed.
- Pose and set keyframes for an IK system.