Contact, Collision and Congestion

Nobuyuki Umetani

Interactive Hybrid Simulation of Large-Scale Traffic

Jason Sewall (Intel Corporation), David Wilkie, Ming C. Ling (University of North Carolina)

Motivation

• Efficient traffic simulation– Fast– Scalable

• Interactively moving visible region

Method

• Visible Region -> Agent based approach– Solve for each car speed & position

• Invisible Region -> Continuum based approach– Solve for car density average velocity

Visible( Agent Based )

Invisible (Continuum Based )

Agent Generation from Continuum data

• Stochastic Theory– Model Car distances with Poisson’s distribution

– For the accuracy, λ is function of x, not constant

Performance – Scalability

Pattern-Guided Smoke Animation with Lagrangian Coherent Structure

Zhi Yuan, Fan Chen, Ye Zhao (Kent State University)

Motivation

• Fit hi-res fluid simulation to low-res simulation– hi-res : detail, expensive– Low-res : no detail, cheap, controllable

Low-Res Hi-Res

Method• Extract skeleton from low-res fluid simulation• Fluid skeleton : Lagrangian Coherent Structure(LCS)• LCS is computed from FTLE(finite-time Lyapunov exponent)

• Assimilate high-res fluid velocity to low-res at LCS

Computation of LCS

FTLS 0 thinning 5 thinning 10 thinning

Interference Aware Geometric Modeling

David Harmon (New York University), Daniele Panozzo (University of Genova), Olga Sorkine (ETH Zurich), Denis Zorin (New York University)

Motivation

• Deform Surface avoiding penetration– Interactive Speed– Various type surface• Close/non-close mesh• Subdivision surface

Method• Space-time frame work• Space-time Interference Volume(STIV)

Framework

Imperceptible Relaxation of Collision Avoidance Constraints in Virtual Crowds

Richard Kulpa, Anne-Helene Olivier Jan Ondrej, Julien Pettre (INRIA, Grenoble, France)

A Hybrid Iterative Solver for Robustly Capturing Coulomb Friction in Hair Dynamics

Gilles Daviet, Florence Bertails-Descoubes, Laurence Boissieux (INRIA, Grenoble, France)