Embedded IPC

Abstract

Physics-based simulation is essential for developing and evaluating robot manipulation policies, particularly in scenarios involving deformable objects and complex contact interactions. However, existing simulators often struggle to balance computational efficiency with numerical accuracy, especially when modeling deformable materials with frictional contact constraints. We introduce an efficient subspace representation for the Incremental Potential Contact (IPC) method, leveraging model reduction to decrease the number of degrees of freedom. Our approach decouples simulation complexity from the resolution of the input model by representing elasticity in a low-resolution subspace while maintaining collision constraints on an embedded high-resolution surface. Our barrier formulation ensures intersection-free trajectories and configurations regardless of material stiffness, time step size, or contact severity. We validate our simulator through quantitative experiments with a soft bubble gripper grasping and qualitative demonstrations of placing a plate on a dish rack. The results demonstrate our simulator's efficiency, physical accuracy, computational stability, and robust handling of frictional contact, making it well-suited for generating demonstration data and evaluating downstream robot training applications. 

Video

Overview

  We solve contact simulation problems in a low-dimensional reduced subspace to gain high efficiency and provide an intersection-free guarantee using the Incremental Potential Contact (IPC) method. 

  To construct such a reduced subspace, we first bind a low-resolution embedding mesh highlighted in blue with the original high-resolution orange mesh of the object. We compute the incremental potential energy due to elasticity, inertia energy, and external force, on the embedding mesh. The barrier and frictional energy are computed on the original high-resolution mesh for contact handling.

  Consequently, our method enjoys an efficiency boost from solving elasticity on a coarse embedding mesh, while maintaining accurate collision handling with the fine collision mesh.

Paper and Supplementary Materials

Paper 

Technical Details

Codes

Coming soon. 

Results

Contact-rich Simulations

Soft Body Deformation