PhysicallyBased 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 Postdocs

• Bill Baxter (graduating Ph.D. student)
• Nico Galoppo
• Naga Govindaraju (Research Associate)
• Nitin Jain
• Ted Kim (graduating Ph.D. student)
• Miguel Otaduy (graduating Ph.D. student)
• Stephane Redon (Postdoc)
• Brian Salomon
• Avneesh Sud
• Gokul Varadhan (graduating Ph.D. student)
• Kelly Ward (graduating Ph.D. student)
• Jeremey Wendt
• Sung-Eui Yoon

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Current Research Interests

• Physics-Based Modeling, Simulation and Animation
• Robot Algorithms in Physical World and Virtual
  Environments
• Haptic Rendering 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 (next)
• 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/
• Live demos on Friday 6-8pm and during breaks

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Geometric Modeling

• Manochas presentation (next)
• 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
• Live demos on Friday 6-8pm and during breaks

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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
• 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
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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 Grahics 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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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/ Govindaraju, et al, GH03
VRST04
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Fast 3D Distance Field Computation using GPU
http//gamma.cs.unc.edu/DiFi Sud, et al. 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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Recent Results 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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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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Recent Results SWIFT

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

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Simulation of Deformable Bodies
Video demonstrations available at http//gamma.cs
.unc.edu/DDF
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Research Challenges

• Real-time modeling 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, 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
• 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
• See the demonstrations at
• Friday, 8/20/04, breaks, Lower Lobby
• Friday, 8/20/04, 600pm-700pm, G-Lab

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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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Research Challenges

• Planning of flexible objects
• Planning with additional constraints (e.g.
  visibility, distance, etc)
• Real-time controllerplanner using graphics
  hardware
• Incorporation of direct human interaction
• Applications to character animation, behavior
  planning of avatars

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System Demonstrations

• Check out the video clips papers at
• http//gamma.cs.unc.edu/planning

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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)
• Henry Fuchs (Medical Apps)
• Fred Brooks (interaction with VE)
• Mary Whitton (interaction with VE)
• Brent Seal (surgical training)

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Supporting Field of Study

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