Physically-Based Modeling, Simulation and Animation Ming C. Lin

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Physically-Based Modeling, Simulation and
Animation Ming C. Lin
lin_at_cs.unc.edu http//www.cs.unc.edu/lin http
//gamma.cs.unc.edu/
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GAMMA Research Group

• Geometric Algorithms for Motion, Modeling and
  Animation

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Faculty

• Ming C. Lin
• Dinesh Manocha

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Graduate Students

• Lakulish Antani
• Abhinav Golas
• Anish Chandak
• Russell Gayle (DOE Fellow)
• Stephen Guy (Intel Fellow)
• Sean Curtis
• Christian LauterbachHuai-Ping Lee
• Ravish Mehra
• Paul Merrell
• Qi Mo

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Graduate Students

• Will Moss
• Rahul Narain (Intel Fellow)
• Nikunj Raghuvanshi
• Zhimin Ren
• Jason Sewall (CS Alumni Fellow)
• Jamie Snape
• Micah Taylor
• David Wilkie
• Yero Heh
• Liangjun Zhang (NSF-CI Fellow)
• Yu Zheng

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Current Research Interests

• Physics-Based Modeling, Simulation and Animation
• Robot Algorithms in Physical World and Virtual
  Environments
• Multi-sensory Interaction Applications
• General Purpose Computing on GPUs
• Rendering Acceleration Techniques for Massive
  Models
• Geometric and Solid Modeling

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Rendering Acceleration and Interaction with
Massive Models

• Manochas presentation and see
• http//www.cs.unc.edu/walk
• http//gamma.cs.unc.edu/Shadow/
• http//gamma.cs.unc.edu/VDR
• http//gamma.cs.unc.edu/CULLIDE
• http//gamma.cs.unc.edu/switch
• http//gamma.cs.unc.edu/Navigation
• http//gamma.cs.unc.edu/GigaWalk/

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GPGPU Geometric Modeling

• Manochas presentation and see
• http//gamma.cs.unc.edu/hardware
• http//gamma.cs.unc.edu/DiFi
• http//gamma.cs.unc.edu/recons
• http//gamma.cs.unc.edu/maxnorm
• http//gamma.cs.unc.edu/SV
• http//gamma.cs.unc.edu/OOC

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Physically-Based Modeling, Simulation and
Animation

• Interactive Proximity Queries
• fast collision detection for flexible bodies
• physically-based geometric algorithms
• Framework for Automatic Simplification of Dynamic
  Simulation
• metrics switching btw simultion LODs
• Simulation of Flexible Bodies and Natural
  Phenomena

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Our Recent Work

• Computation of gen. Voronoi diagram proximity
  queries using graphics processors
• http//gamma.cs.unc.edu/voronoi,PIVOT,CULLIDE
  ,DiFi
• Interactive collision detection
• gamma.cs.unc.edu/Collision_mpeg/collision.html
  
• Simulation Level of Detail
• gamma.cs.unc.edu/SLOD, gamma.cs.unc.edu/HSLOD
• Modeling deformable bodies nature
• gamma.cs.unc.edu/ffd, fem, DDF, HAIR, ICE,
  HYB_ICE, LIGHTNING, QCULLIDE
• 3D polyhedral morphing
• gamma.cs.unc.edu/3Dmorphing

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Simulation of Dendritic Ice Growth
http//gamma.cs.unc.edu/ICE http//gamma.cs.unc.ed
u/HYB_ICE Kim Lin, SCA 2003 SCA 2004 SCA
2006
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A Physically-based Lightning Model

• Based on dielectric breakdown model for electric
  discharge
• Animation of sustained electrical streams by
  solving a simplified Helmholtz Eqn. for
  propagating electromagnetic waves
• A fast, accurate rendering method using a
  convolution kernel
• A parameterization that enables simple artistic
  control
• http//gamma.cs.unc.edu/LIGHTNING
• Kim Lin, Pacific Graphics 2004

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Hair Simulation Using LODs
http//gamma.cs.unc.edu/HSLOD http//gamma.cs.unc.
edu/HAIR http//gamma.cs.unc.edu/HairWS Ward, et
al, CASA 2003 PG 2003 CASA 2004
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Adaptive Dynamics

• Automatic simplification of forward dynamics for
  articulated bodies based on motion error metrics
  using a hybrid-body representation, achieving up
  to two orders of magnitude performance gain
• Redon, Galoppo, Lin SIGGRAPH 2005

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Collision Detection Using GPU

• Applicable to deformable breakable objects with
  changing topology
• Use occlusion culling for collision tests
• Unified framework for both intra- and inter-
  object collision culling

http//gamma.cs.unc.edu/CULLIDE/ http//gamma.cs.u
nc.edu/RCULLIDE/ http//gamma.cs.unc.edu/QCULLIDE/
http//gamma.cs.unc.edu/CDCD/ Govindaraju, et
al, GH03 VRST04 VR05 SIGGRAPH05
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Collision Detection for Deformable Models using
Chromatic Decomposition.
http//gamma.cs.unc.edu/CDCD/ Govindaraju, et
al SIGGRAPH 2005
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Fast 3D Distance Field Computation using GPU
http//gamma.cs.unc.edu/DiFi Sud, et al.
Eurographics 2004
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Constraint-based Planning
Application to Car Painting (Left) Assembly
(Right) http//gamma.cs.unc.edu/cplan,DiFi
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Computation using GPUPenetration Depth
Computation
Dynamic Simulation
Virtual Prototyping
Haptic Rendering
http//gamma.cs.unc.edu/DEEP http//gamma.cs.unc.e
du/PD
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PIVOT2D

• Proximity Queries Using Graphics Hardware
  Acceleration

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PIVOT Simulation of Randomly Moving Gears
Letter Blocks

• http//gamma.cs.unc.edu/PIVOT

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PIVOT2D Deformation of Jello
http//gamma.cs.unc.edu/PIVOT
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SWIFT/SWIFT

• Use of Multiresolution Reps Coherence
• Ehmann Lin, Eurographics 2001

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Multires Collision Detection

• Introduction of Dual-Hierarchy
• Contact-dependent Simplification use of contact
  level-of-detail

http//gamma.cs.unc.edu/CLOD http//gamma.cs.unc.e
du/MRC Otaduy Lin, SGP03 Yoon, et al,
SGP04
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Simulation of Deformable Bodies
Video demonstrations available at http//gamma.cs
.unc.edu/DDF
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Fast Contact Handling Using Dynamic Deformation
Textures
http//gamma.cs.unc.edu/ABDefo/ http//gamma.cs.un
c.edu/D2T/
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Texturing Fluids
http//gamma.cs.unc.edu/TexturingFluids/ http//ga
mma.cs.unc.edu/DTS_FLOW/
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More Fluids

• Explosion Compressible Fluids ACM SIGGRAPH/EG
  Symposium on Computer Animation
• http//gamma.cs.unc.edu/SHOCK/
• Fluids in Video Eurographics 2008
• http//gamma.cs.unc.edu/FluidInVideo
• Turbulence SiGGRAPH Asia 2008
• http//gamma.cs.unc.edu/turbulence/

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Research Challenges

• Real-time modeling, cutting, and control of
  deformable materials (e.g. soft tissues organs,
  fibrin fibers in blood flow, virtual clay)
• Interactive simulation rendering using LOD
  representations
• Simulation of water droplets, ice/lightning/snow
  formation/melting, interface between
  fluiddeformable, etc.

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Future Applications

• Virtual scultping
• Real-time interaction with VEs
• Task training rehearsal, prototyping of
  experimentation, etc.
• Surgical training system modeling virtual sinus
• nanoSimulator better behavior modeling through
  realistic interaction manipulation
• Modeling and simulation of fibrin fibers
• CG special effects

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System Demonstrations

• Check out the video clips papers at
• http//gamma.cs.unc.edu/collide
• http//gamma.cs.unc.edu/simulation
• And
• http//www.cs.unc.edu/lin/

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Current Research Interests

• Physics-Based Modeling, Simulation and Animation
• Robot Algorithms in Physical World and Virtual
  Environments
• Multi-sensory Interaction Applications
• General Purpose Computing on GPUs
• Rendering Acceleration Techniques for Massive
  Models
• Geometric and Solid Modeling

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Robot Algorithms for Physical World Virtual
Environments

• Motion Planning with Multiple Degrees of Freedom
  and Constraints
• acquiring real-world data for IBR/VBR
• task planning of autonomous characters
• high-level motion generation
• navigation toolkit for virtual environments
• manipulation of flexible plates/materials for
  medical tool design and surgical planning
  maintainability study of parts
• computer-assisted parts assembly

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Real-time Motion Planning Dynamic Scene
Distance buffer of floor-plan used as potential
field
Plan motion of music stand around moving furniture
http//gamma.cs.unc.edu/planning/videos.shtml
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Constraint-based Planning
Application to Car Painting (Left) Assembly
(Right) http//gamma.cs.unc.edu/cplan
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Planning of Deformable Robots

• Planning of flexible models
• Physically-based modeling
• Constraint-based planning
• Handling of both rigid and
• deforming obstacles
• Use of GPU
• Fast (real-time for simpler robots and
  environments)
• http//gamma.cs.unc.edu/DPLAN
• http//gamma.cs.unc.edu/FlexiPLAN

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Real-time Motion Planning of Multiple-Agents in
Dynamic Scene
Crowd Simulations
Game-Like Applications
http//gamma.cs.unc.edu/crowd http//gamma.cs.unc.
edu/CompAgent
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Research Challenges

• Planning of multiple flexible robots
• Planning with additional constraints (e.g.
  visibility, distance, etc)
• Real-time controllerplanner using graphics
  hardware (GPU) or multi-core architecture for
  model acquisition
• Incorporation of direct human interaction
• Applications to character animation, crowd
  simulations, and behavior planning of avatars

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System Demonstrations

• Check out the video clips papers at
• http//gamma.cs.unc.edu/planning
• And
• Demos in G-Lab tonight!!!

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Current Research Interests

• Physics-Based Modeling, Simulation and Animation
• Robot Algorithms in Physical World and Virtual
  Environments
• Multi-sensory Interaction Applications
• General Purpose Computing on GPUs
• Rendering Acceleration Techniques for Massive
  Models
• Geometric and Solid Modeling

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Multi-Sensory Interaction

• http//gamma.cs.unc.edu/Sound
• http//gamma.cs.unc.edu/symphony
• http//gamma.cs.unc.edu/SoundingLiquids
• http//gamma.cs.unc.edu/dab/

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Technology Transfer

• CAD/CAM Engineering Simulation MDI/Adams,
  Knowledge Revolution, etc.
• Computer Animation/Human Modeling
• Jack (UPENN), Transom Technology/EAI
• Virtual Prototyping VEs Division, Prosolvia,
  AmadaSoft, Ford, etc.
• Robotics Automation Kawasaki
• Interactive Games Intel ISVs, Blaxxun
• Medical Simulation ADAC Lab

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Collaborators

• Robotics HRL, Stanford University
• Interactive Games Intel ISVs
• Haptics SensAble, Immersion, etc.
• Virtual Prototyping Boeing, Ford, Sandia, etc.

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Other Faculty Members

• Russell Taylor (nanoManipulator)
• Paul Segars (JHU, Radiology)
• Henry Fuchs (teleimmersion)
• Fred Brooks (interaction with VE)
• Mary Whitton (interaction with VE)
• Brent Seal (surgical training)

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RA Work

• Under the supervision of advisors,
• Research and understand existing work
• Design and implement new algorithms
• Test resulting systems on compelling applications
  and show the validity of the proposed approaches
• Write papers and submit them to top conferences
  and journals

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Required Background

• Physically-based Modeling
• Dynamic Simulation
• Computer Animation
• Robot Motion Planning
• Haptics

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Supporting Field of Study

• Graphics User Interface
• Computational Geometry
• Geometric Solid Modeling
• Numerical Analysis
• Physics Mechanics
• Robotics