cartoon motion and deformation of skeletons ting ting wu advisor – nancy pollard
DESCRIPTION
Background/Motivation Most people pick this one - Anticipation and Follow-through - Stretch and SquashTRANSCRIPT
Cartoon Motion and Deformation of Skeletons
Ting Ting WuAdvisor – Nancy Pollard
Background/MotivationWhich looks more interesting?
Which looks more interesting?
Background/Motivation
Most people pick this one
- Anticipation and Follow-through- Stretch and Squash
2 Ways to Apply Stretch and Squash
- posture
- body parts/limbs
(PowerPoint didn’t like video clip…)
Stretch and Squash in 3D- used extensive for postures
- hardly used at all for limbs
Stretch and Squash in 3D- used extensive for postures
- hardly used at all for limbs
well… one notable exception
Stretch and Squash in 3D- used extensive for postures
- hardly used at all for limbs
GoalAdd “cartoony-ness” into motion-captured data or key-framed data
Goal
Add “cartoony-ness” into motion-captured data or key-framed data
2 Ways to approach this
- using a physical system to model skeleton deformations
+ get different deformations by changing a few intuitive variables (mass, springyness)
- using a filter that only looks at motion curves
+ more aligned with original 2D animation methods (?)
Physical System - Initial Steps-Rotoscoped Mickey’s walk in Maya
-Motion-captured an actor mimicking Mickey’s walk
(videos…)
Bone LengthsHere are the main bones that change lengths to contribute to expression.
Bone LengthsHere are the main bones that change lengths to contribute to expression.
Mass at thorax
Anchor at upperback
Mass at root
Variables
Each spring abides by this equation.
f = m*a = -k*d – b*v
Where
d = length – spring’s rest length
k = spring stiffness coefficient
b = damping coefficient
length
Cartoon Motion and Deformation of Skeletons
Ting Ting WuAdvisor – Nancy Pollard
Background/MotivationWhich looks more interesting?
Which looks more interesting?
Background/Motivation
Most people pick this one
- Anticipation and Follow-through- Stretch and Squash
2 Ways to Apply Stretch and Squash
- posture
- body parts/limbs
(PowerPoint didn’t like video clip…)
Stretch and Squash in 3D- used extensive for postures
- hardly used at all for limbs
Stretch and Squash in 3D- used extensive for postures
- hardly used at all for limbs
well… one notable exception
Stretch and Squash in 3D- used extensive for postures
- hardly used at all for limbs
GoalAdd “cartoony-ness” into motion-captured data or key-framed data
Goal
Add “cartoony-ness” into motion-captured data or key-framed data
2 Ways to approach this
- using a physical system to model skeleton deformations
+ get different deformations by changing a few intuitive variables (mass, springyness)
- using a filter that only looks at motion curves
+ more aligned with original 2D animation methods (?)
Physical System - Initial Steps-Rotoscoped Mickey’s walk in Maya
-Motion-captured an actor mimicking Mickey’s walk
(videos…)
Bone LengthsHere are the main bones that change lengths to contribute to expression.
Bone LengthsHere are the main bones that change lengths to contribute to expression.
Mass at thorax
Anchor at upperback
Mass at root
Variables
Each spring abides by this equation.
f = m*a = -k*d – b*v
Where
d = length – spring’s rest length
k = spring stiffness coefficient
b = damping coefficient
length
Variables
Each spring abides by this equation.
f = m*a = -k*d – b*v
Multiple Linear Regression to get k and b!
Should contain the “springyness” of Mickey’s walk.
Ideally, this should allow us to transfer the same kind of stretching and squashing to another moving skeleton.
length
Some of the Data
Plots of d
Some of the Data
Plots of force acting on spring