Alexandria Digital Research Library

Efficient deformations using custom coordinate systems

Teng, Yun
Degree Supervisor:
Theodore Kim and Tobias Hollerer
Place of Publication:
[Santa Barbara, Calif.]
University of California, Santa Barbara
Creation Date:
Issued Date:
Computer science
Collision resolution
Physics-based animation
Online resources and Dissertations, Academic
Degree Grantor:
University of California, Santa Barbara. Computer Science
Ph.D.--University of California, Santa Barbara, 2016

Physics-based deformable object simulations have been playing an increasingly important role in 3D computer graphics. They have been adopted for humanoid character animations as well as special effects such as fire and explosion. However, simulations of large, complex systems can consume large amounts of computation and mostly remain offline, which prohibits their use for interactive applications.

We present several highly efficient schemes for deformable object simulation using custom spatial coordinate systems. Our choices span the spectrum of subspace to full space and both Lagrangian and Eulerian viewpoints.

Subspace methods achieve massive speedups over their "full space" counterparts by drastically reducing the degrees of freedom involved in the simulation. A long standing difficulty in subspace simulation is incorporating various non-linearities. They introduce expensive computational bottlenecks and quite often cause novel deformations that are outside the span of the subspace.

We address these issues in articulated deformable body simulations from a Lagrangian viewpoint. We remove the computational bottleneck of articulated self-contact handling by deploying a pose-space cubature scheme, a generalization of the standard "cubature" approximation. To handle novel deformations caused by arbitrary external collisions, we introduce a generic approach called subspace condensation, which activates full space simulation on the fly when an out-of-basis event is encountered. Our proposed framework efficiently incorporates various non-linearities and allows subspace methods to be used in cases where they previously would not have been considered.

Deformable solids can interact not only with each other, but also with fluids. We design a new full space method that achieves a two-way coupling between deformable solids and an incompressible fluid where the underlying geometric representation is entirely Eulerian. No-slip boundary conditions are automatically satisfied by imposing a global divergence-free condition. We are able to simulate multiple solids undergoing complex, frictional contact while simultaneously interacting with a fluid. The complexity of the scenarios we are able to simulate surpasses those that we have seen from any previous method.

Physical Description:
1 online resource (131 pages)
UCSB electronic theses and dissertations
Catalog System Number:
Inc.icon only.dark In Copyright
Copyright Holder:
Yun Teng
File Description
Access: Public access
Teng_ucsb_0035D_13176.pdf pdf (Portable Document Format)