Reflections on Simultaneous Impact

Breannan Smith, Danny Kaufman, Etienne Vouga, Rasmus Tamstorf, Eitan Grinspun Resolving simultaneous impacts is an open and significant problem in collision response modeling. Existing algorithms in this domain fail to fulfill at least one of five physical desiderata. To address this we present a simple generalized impact model motivated by both the successes and pitfalls […]

Interactive Editing of Deformable Simulations

Jernej Barbic, Funshing Sin, Eitan Grinspun We present an interactive animation editor for complex deformable object animations. Given an existing animation, the artist directly manipulates the deformable body at any time frame, and the surrounding animation immediately adjusts in response. The automatic adjustments are designed to respect physics, preserve detail in both the input motion […]

PolyDepth: Real-Time Penetration Depth Computation using Iterative Contact-Space Projection

Changsoo Je, Min Tang, Youngeun Lee, Minkyoung Lee, Young J. Kim We present a real-time algorithm that finds the Penetration Depth (PD) between general polygonal models based on iterative and local optimization techniques. Given an in-collision configuration of an object in configuration space, we find an initial collision-free configuration using several methods such as centroid […]

Efficient Geometrically Exact Continuous Collision Detection

Tyson Brochu, Essex Edwards, Robert Bridson Continuous collision detection (CCD) between deforming triangle mesh elements in 3D is a critical tool for many applications. The standard method involving a cubic polynomial solver is vulnerable to rounding error, requiring the use of ad hoc tolerances, and nevertheless is particularly fragile in (near-)planar cases. Even with per-simulation […]

Continuous Penalty Forces

Min Tang, Dinesh Manocha, Miguel Otaduy, Ruofeng Tong We present a simple algorithm to compute continuous penalty forces to determine collision response between rigid and deformable models bounded by triangle meshes. Our algorithm provides a well-behaved solution in contrast to the traditional stability and robustness problems of penalty methods, induced by force discontinuities. We trace […]

STAR: Interactive Simulation of Rigid Body Dynamics in Computer Graphics

Jan Bender, Kenny Erleben, Jeff Trinkle, Erwin Coumans Interactive rigid body simulation is an important part of many modern computer tools. No authoring tool nor a game engine can do without. The high performance computer tools open up new possibilities for changing how designers, engineers, modelers and animators work with their design problems. This paper […]

VolCCD: Fast Continuous Collision Culling Between Deforming Volume Meshes

Min Tang, Dinesh Manocha, Sung-Eui Yoon, Peng Du, Jae-Pil Heo, Ruofeng Tong We present a novel culling algorithm to perform fast and robust continuous collision detection between deforming volume meshes. This includes a continuous separating axis test that can conservatively check whether two volume meshes overlap during a given time interval. Moreover, we present efficient […]

Asynchronous Integration with Phantom Meshes

David Harmon, Qingnan Zhou, Denis Zorin Asynchronous variational integration of layered contact models provides a framework for robust collision handling, correct physical behavior, and guaranteed eventual resolution of even the most difficult contact problems. Yet, even for low-contact scenarios, this approach is significantly slower compared to its less robust alternatives — often due to handling […]

Eulerian Solid Simulation with Contact

David I. W. Levin, Joshua Litven, Garrett L. Jones, Shinjiro Sueda, Dinesh K. Pai Simulating viscoelastic solids undergoing large, nonlinear deformations in close contact is challenging. In addition to inter-object contact, methods relying on Lagrangian discretizations must handle degenerate cases by explicitly remeshing or resampling the object. Eulerian methods, which discretize space itself, provide an […]

SPH Granular Flow with Friction and Cohesion

Ivan Alduan, Miguel Otaduy Combining mechanical properties of solids and fluids, granular materials pose important challenges for the design of algorithms for realistic animation. In this paper, we present a simulation algorithm based on smoothed particle hydrodynamics (SPH) that succeeds in modeling important features of the behavior of granular materials. These features are unilateral incompressibility, […]