English

Convergence proof for first-order position-based dynamics: An efficient scheme for inequality constrained ODEs

Numerical Analysis 2023-10-04 v2 Numerical Analysis

Abstract

NVIDIA researchers have pioneered an explicit method, position-based dynamics (PBD), for simulating systems with contact forces, gaining widespread use in computer graphics and animation. While the method yields visually compelling real-time simulations with surprising numerical stability, its scientific validity has been questioned due to a lack of rigorous analysis. In this paper, we introduce a new mathematical convergence analysis specifically tailored for PBD applied to first-order dynamics. Utilizing newly derived bounds for projections onto uniformly prox-regular sets, our proof extends classical compactness arguments. Our work paves the way for the reliable application of PBD in various scientific and engineering fields, including particle simulations with volume exclusion, agent-based models in mathematical biology or inequality-constrained gradient-flow models.

Keywords

Cite

@article{arxiv.2310.01215,
  title  = {Convergence proof for first-order position-based dynamics: An efficient scheme for inequality constrained ODEs},
  author = {Steffen Plunder and Sara Merino-Aceituno},
  journal= {arXiv preprint arXiv:2310.01215},
  year   = {2023}
}

Comments

37 pages, 11 figures

R2 v1 2026-06-28T12:38:18.853Z