Rig design process Part 6 Arc

The difference between the IK and FK

In real life, organic creatures always move in arcs or a sort of figure “8”. Our hands move naturally in arcs when we gesture or when we are just swinging them at our sides. Our hips move up and down in arcs as we walk. When you rotate a joint in a 3d program, it will actually naturally move through an arc, just as that joint would move in real life. Sometimes we don't want the lower nodes in a hierarchy to move with the upper nodes. You could manually go frame by frame and animate the joints keep in the some position but that is extremely tedious. Instead, you can set up an Inverse Kinematics chain that will lock joint and figure out the calculations you. However, there will also be no arc to the motion of an IK control, it moves linearly between poses. Where you naturally have an arc in the FK control, you will have to add arcs manually in the one with IK.

Rig design process Part 5 Follow through and Overlapping

The overlapping on the nose and head and the broken joint


Parts of characters does not move all at once, but instead it stretch, catches up, twists, turns, and contracts as the forms work against each other,. As one part arrives at the stopping point, others may still be in movement. The loose flesh on a figure, such as cheeks, will move art a slower speed than the skeletal parts. The most obvious example of overlapping action is the “broken joints”, to get some flexibility in limbs swing; we will break or bend the elbow or knee joint. It looks more natural even though it is against the anatomical limitation. The lack of control when we animate with inverse kinematics may make it more difficult to get it into the exact position you want. It is significant if we can switch between IK and FK to animate according to situation of the characters.

Rig design process Part 4 Staging

Character is bended to emphasize the “line of Action”

The silhouette doesn’t reveal what is happening with the character

The silhouette should be clear enough to help audience get the idea

Staging is about the presentation of idea from the characters; silhouette and line of action are two significant elements underneath that principle. Good staging in your camera view will allow audience to clearly and quickly understand what is going on in scene. It is important to keep in mind that we are still working with two dimensional projected images, even though we animate the rig and model in the three dimensional environments. A strong Silhouette is mostly important in “cartoony” animation; pose and animation should be very clean to audience to make a stronger statement. Line of action shows the direction of movement of the main mass of the character, line of action should not be straight, curve and arc for the line of action shows the direction and the fluency of action, that kind of rubber hose limb and body is against the idea of joints. Under the necessity, the rigs are rigid; we cannot bend the character for the smooth curve line of action. We have create some extras for bending the character which have to be driven by the originally rig.

Rig design process Part 3 Exaggeration

Exaggerated pose advanced the “cartoony” style



In the “cartoony” animation, exaggeration is pushed something beyond what you think is natural and realistic, it helps achieve a stronger dramatic or comedic effects, is a useful way to emphasize the emotion or humor. The more exaggerated your animation, the more “cartoony” it will look. In terms of pose, the intention of exaggerate the pose of characters is effective communication. The pose should be strong enough for the audience to get what is happening with the characters by read one image of the characters.
In order to push the pose exaggerate and “cartoony “enough for audience, the rig should be able to perform a kind of broken effects and without any limitation.

Rig design process Part 2 Squash and Stretch

Squash and stretch shows the direction of force and the senses of speed





In the 12 principles, some are important in considering character rigs such as Squash and Stretch. It is the most foundational principle but it was only recently be appreciated in CG world, CG movies such as “Open Season” and Madagascar”, the new squash and stretch treatments of character has become a significant element. Elements can be compressed by itself, expanded and stretch out .the variation of the rigidity makes characters more freshly and achieving a more comedic effect, it also can emphasize scene of speed and weight.

Smear is text of squash and stretch which had been discovered by Check Jones, cartoon director of Warner Brothers, instead of brush stroke, the images of the characters were smeared in the in-between which emphasized of the scene of speed and the fluency of the movement could not be replaced by motion blur.
In item of character rigging, the character should be able to wholly and partly deform, limb, torso and head should be deformed and smeared individually.

Rig design process Part 1 12 Principles

Before jump in and start working on a character rig, we should think ahead and to realize what the exact requirements of the rig in order to achieve the animate production. This will save our time by creating only what is necessary. The main theme of my project is the development of “cartoony” character and animation. Before we started get into the further section, it is necessary to understand and clarify what are “cartoony” motion, emotion, and the interaction with the environments.

When we talk about the “cartoony”, we are talking about the rubber hose characters, the red carpet tongues, bulging eyes; we are talking about the style of animation developed in the twenties at Disney and Warner Brothers.

In order to train young animators, the principles of animation were created in the early 1930s by the animators Walt Disney Studios. These principles became one of the foundations of hand-drawn cartoon character animation, as they are commonly referred to, also helped to transform animation from a novelty into an art form. The best way to determine the requirements of our rigs is get relevant reference such as those principles of animation.

According to the book " Illusion of Life" , the principles of animation are :

1. Squash and stretch
2. Anticipation
3. Staging
4. Straight-ahead action and pose-to-pose
5. Follow-through and overlapping action
6. Slow-in and slow-out
7. Secondary action
8. Timing
9. Arcs
10. Exaggeration
11. Solid drawing
12. Appeal

The original principles are still relevant today because they help us to create more believable characters and situations. These principles originally referred to 2D characters, we must consider how apply those principle into our characters.