EqCollide: Equivariant and Collision-Aware Deformable Objects Neural Simulator
For researchers in physics simulation and robotics, this work addresses the lack of equivariance and collision handling in data-driven deformable object simulators, offering improved accuracy and scalability.
EqCollide is the first end-to-end equivariant neural fields simulator for deformable objects and collisions, achieving 24.34% to 57.62% lower rollout MSE than baselines across 2D and 3D scenarios, with generalization to more objects and longer horizons.
Simulating collisions of deformable objects is a fundamental yet challenging task due to the complexity of modeling solid mechanics and multi-body interactions. Existing data-driven methods often suffer from lack of equivariance to physical symmetries, inadequate handling of collisions, and limited scalability. Here we introduce \name, the first end-to-end equivariant neural fields simulator for deformable objects and their collisions. We propose an equivariant encoder to map object geometry and velocity into latent control points. A subsequent equivariant Graph Neural Network-based Neural Ordinary Differential Equation models the interactions among control points via collision-aware message passing. To reconstruct velocity fields, we query a neural field conditioned on control point features, enabling continuous and resolution-independent motion predictions. Experimental results on 2D and 3D scenarios show that \name achieves accurate, stable, and scalable simulations across diverse object configurations. It achieves $24.34\%$ to $57.62\%$ lower rollout MSE, even compared with the best-performing baseline model. Furthermore, \name could generalize to more colliding objects and extended temporal horizons, and stay robust to input transformed with group action. Code is available at: https://github.com/AI4Science-WestlakeU/EqCollide