1 Virtual Characters

Two Types UserComputer 2 AvatarAgent

Avatars What affordances do they provide? What affordances do they provide? What should/can they look like? What should/can they look like? How are they be controlled? How are they be controlled? –What should be controlled? How do they transform real interaction? How do they transform real interaction? 3

Agents How realistic can their behavior be? How realistic can their behavior be? What is their effect on performance/behavior of real human? What is their effect on performance/behavior of real human? Where are they be applied? Where are they be applied? 4

Virtual Bodies Virtual Characters Virtual Characters Virtual Humans Virtual Humans 5

Copresence How do people respond to Virtual Humans? How do people respond to Virtual Humans? –PI?  Being “with” another person –PSI?  Behaving as though that other person is real in spite of knowledge otherwise Uses in psychology, interpersonal skills training Uses in psychology, interpersonal skills training PI bounded by immersion PI bounded by immersion –Motion and Voice Capture, Display technology PSI exists despite best our attempts to ruin it PSI exists despite best our attempts to ruin it –Confirmed by studies in interpersonal behaviors with virtual humans (Bailenson, Slater, Johnsen) 6

Increasing Copresence (PSI) Rendering should match capability Rendering should match capability Rendering Rendering –Display, graphics, voice, haptics, motion Capabilities Capabilities –Perception/Intelligence Better to have low-quality rendering with little capability and high-quality rendering with more capability Better to have low-quality rendering with little capability and high-quality rendering with more capability –Matches user expectations 7

The Uncanny Valley 8

9

Where can you get Virtual Humans? Evolver ( Evolver ( –$40 a piece + $30 for face animation –Export directly to format of your choice (Ogre available) –Requires animation Makehuman Makehuman –Free, but more difficult to use –No hair, no clothing –Requires some rigging + animation Make your own Make your own –Very time consuming –Modeling + Rigging + Animating Commercial – Vizard Commercial – Vizard –Pricey –Integrated Virtual Reality Solution – 10

Motion Capture Typically expensive: $6000 for cheapest commercial setup, usually about $250k Typically expensive: $6000 for cheapest commercial setup, usually about $250k Typically requires offline step Typically requires offline step FAAST FAAST – /watch?v=Up-9xdXGIQY Face arguably most important… Face arguably most important… 11

Facial Motion Capture More challenging than body motion capture More challenging than body motion capture –Soft body tracking –Must map to control points Excellent solutions available for $$$ Excellent solutions available for $$$ –Encumbrance Some inexpensive solutions exist Some inexpensive solutions exist –Logitech –Microsoft Face Avatars (coming soon) 12

Eye Motion Capture 13 Similar problem to face motion capture Similar problem to face motion capture Head Mounted and Desktop solutions Head Mounted and Desktop solutions Can be incorporated into an HMD Can be incorporated into an HMD Noisy in practice Noisy in practice

Non-Mocap Animation Animation package Animation package –Autodesk 3D Studio Max, Maya, Motion Builder  Free for students –Blender  Free, open source –Motion capture data often a good starting point Mixamo Mixamo –Online site to create and mix together animations that have been previously created 14

Synthesized Animations Computer creates animations based on goals Computer creates animations based on goals –Fundamentally an AI problem (how do humans do it?) Gaze control Gaze control –Often used for both avatars and agents Reaching and grasping Reaching and grasping –Smart objects Some physics simulations exist (difficult to make realistic and real- time) Some physics simulations exist (difficult to make realistic and real- time) –Similar to robotics problems 15

Intelligent Agent Behavior Crowd Simulations Crowd Simulations –Large battle scenes –Surveillance Training –Virtual world population Local interaction models Local interaction models –Gaze  One-on-one  Multi-party –Conversation   Good conference: ACM Intelligent Virtual Agents Good conference: ACM Intelligent Virtual Agents 16

Wizard-of-Oz Fake virtual human agent Fake virtual human agent User led to believe virtual human is computer controlled User led to believe virtual human is computer controlled Typically used for studies on interpersonal behaviors with virtual humans Typically used for studies on interpersonal behaviors with virtual humans –Are these useful studies? Control scheme may be direct or indirect Control scheme may be direct or indirect –Mocap or Selection interface 17