My current research is focused on using fluid simulation techniques to model large aggregates like granular materials, crowds etc.
Free-Flowing
Granular Materials with Two-Way Solid Coupling
Rahul Narain, Abhinav Golas, Ming Lin
Proceedings of ACM SIGGRAPH Asia 2010 (To appear)
We present a novel continuum-based model that enables efficient
simulation of granular materials.Our approach fully solves the
internal pressure and frictional stresses in a granular material,
thereby allows visually noticeable behaviors of granular materials
to be reproduced, including freely dispersing splashes without
cohesion, and a global coupling between friction and pressure.The
full treatment of internal forces in the material also enables
two-way interaction with solid bodies.Our method achieves these
results at only a very small fraction of computational costs of the
comparable particle-based models for granular flows.
Aggregate
Dynamics for Dense Crowd Simulation
Rahul Narain, Abhinav Golas, Sean Curtis, Ming Lin
Proceedings of ACM SIGGRAPH Asia 2009
Large dense crowds show aggregate behavior with reduced individual
freedom of movement. We present a novel, scalable approach for
simulating such crowds, using a dual representation both as discrete
agents and as a single continuous system. In the continuous setting,
we introduce a novel variational constraint called unilateral
incompressibility, to model the large-scale behavior of the crowd,
and accelerate inter-agent collision avoidance in dense scenarios.
This approach makes it possible to simulate very large, dense crowds
composed of up to a hundred thousand agents at near interactive
rates on desktop computers.
Interactive Modeling, Simulation and Control of Large-Scale Crowds
and Traffic
Ming Lin, Stephen Guy, Rahul Narain, Jason Sewall, Sachin Patil,
Jatin Chhugani, Abhinav Golas, Jur van den Berg, Sean Curtis, David
Wilkie, Paul Merrell, Changkyu Kim, Nadathur Satish, Pradeep Dubey,
Dinesh Manocha
Motion in Games 2009
Explosion Simulation using Compressible Fluids
Abhinav Golas, Akram Khan, Prem Kalra, Subodh Kumar
Proceedings of
ICVGIP 2008
We propose a novel physically based method to simulate explosions
and other compressible fluid phenomena. The method uses compressible
Navier Stokes equations for modeling the explosion with a
Semi-Lagrangian integration method. The proposed integration method
addresses the issues of stability and larger time steps. This is
achieved by modifying the Semi-Lagrangian method to reduce
dissipation and increase accuracy, using improved interpolation and
an error correction method. The proposed method allows the rendering
of related phenomena like a fireball, dust and smoke clouds, and the
simulation of solid interaction - like rigid fracture and rigid body
simulation. Our method is flexible enough to afford substantial
artistic control over the behavior of the explosion.