Physical Human Movement Sketches

Fast Muscles, Rutgers.
- some focus on biological accuracy.
- Previous:
- Lines of Force; fail with large muscles with largg contacts.
- FEM/FVM. Difficult to *acquire*
- Approach: "Strand" - fiber-like
- "Unconditionally stable"
- Speed vs. visual accuracy vs. kinematic accuracy
- Cosserat theory of elastic rods. Rubin 200, Pai 2002
- Fibers are Segments divided by nodes. Nodes drive free-form controls that model the muscle volume.
- Separate models for tendons and muscles
- Hill-type muscle model -- Zajac 89., Teran 2003
- first-order numerical method
- "SVD" collisions become contact become equality constraints
- KKT

Interactive and Reactive Dynamic Control; Ari Shapiro
"Fah lout sauce"

"reactive skills"
control methods: kinematic(modifying mocap) vs. dyanmic control
"Fully interactive character"
- "mocap is probably necessary" "needed to do the complicated things that we want (the character) to do"
- "exploration" sytaste of physical control
- Mandel 04, Master's Thesis: Reactive Behaviors

ban De Panne - 2003, ski simulated; 2005, Zhao ***
"virtual humanoid"

RI: training wheels for learning

"i'd love to incorporate massive-like approaches"


Fast Volume Preseveration for Realistic Muscle Deformation.
RI: maybe a variation on the verlet tertrahedron would work for volume preservation in simulated muscles?

AI Characters Panel at Siggraph

Andrew Stern - Facade - Procedural Arts (grandtextauto.org)
Next-gen game machines will spend most of the CPU on feeding the graphics engines-- leaving little behind for AI.

"Balance of visual fidelity and behavioral fidelity." By design.
---

Animation-guy. EA Sports. Canada.
"Issues we need to overcome."
"What does the viewer assess?" -- 1) apperance 2) movement, locomotion, 3) performance.

next-gen: super-realistic visual characters, but the same AI

- how should an AI react to a situation
- how is that reaction conveyed?
- ramifications of the choices.

Next Gen AI: Locomotion and Performance
- Locomotion. "moments of realiaty interrupted by bad transitions" ignoring physics, inertia, etc.
- On ice! Ice skating physics sim :-) what else? swimming?
- attribute-based motion: did he get tripped?
- the "tough part with AI is that you only have so many mo-cap choices-- if you only have one fall, can't distinguish between between pissed off for being tripped or diving for a tackle, or falling shamefully
- anticipation
- "a cycle is a necessity"

Performance.
- situational awareness.
- unique reactions-- star player-cocky on scoring a goal; rookie-excited as hell on a goal.


"Get away from sewing together clips of motion."
"simulation and procedural techniques to create motion"
"animators teach their characters how to behave"
"creating individual behaviors for hundreds or thousands of characters in a game has to be done procedurally"

"first concern of game developers: testing" (does that matter so much for locomotion? presumably not) Moving more toward automated testing. Maybe GAs for test suites? :-)

Major dichotomy: data-driven vs. first-principle results.

In a FPS-- expressing fear vs. boldness: maybe not too hard to extract from player movement. How should teammates respond.

jason oseepa - "Stop Staring"

"motion capture will be just another training technique for the procedural motion"