Eitan Grinspun (Computer Science, Columbia University)
Wednesday, 9.6.2010, 11:30
We would like to compute the motion of flexible materials colliding against each other in complex ways (e.g., sheets of fabric being knotted, plastic and metal containers crushed in a trash compactor). Such computations are needed in special effects, engineering design, medical simulation, and any other domain that requires consideration of materials interacting against each other. What is a "good" way to carry out such computations?
What sets our approach apart from previous attempts is our focus on three guarantees: that simulations of well-posed problems (a) have no interpenetrations, (b) obey causality, momentum- and energy-conservation laws, and (c) complete in finite time. While these three requirements may seem natural to ask of a computation, we will show that previous methods can be grouped into three families, each family sacrificing one of the three guarantees for the sake of the other two. Various 2D and 3D examples will illustrate why a single method offering all three guarantees can serve as a powerful simulation tool.
This talk will be given at a tutorial level, without assuming prior knowledge of motion computation or collision response algorithms.
*This is joint work with David Harmon, Etienne Vouga, Breannan Smith, and Rasmus Tamstorf