Unlocking Thickness Modeling for Codimensional Contact Simulation

2025-10-11

AI Summary

Existing co-dimensional thick-shell models suffer from severe locking artifacts and geometric interpenetration during high-resolution simulation of woven/knitted fabrics, due to unphysical contact forces between adjacent discrete elements—leading to numerical instability. This work proposes an improved co-dimensional contact treatment algorithm integrating the Incremental Potential Contact (IPC) barrier theory, enabling, for the first time, locking-free and penetration-free high-resolution thick-shell simulation. The method is compatible with both rod- and shell-based representations, requires neither resolution reduction nor contact-pair culling, and significantly enhances accuracy, robustness, and physical consistency. Extensive validation across diverse real-world fabric architectures and dynamic loading scenarios demonstrates stable, high-fidelity simulation under realistic material parameters—overcoming the longstanding accuracy–stability trade-off inherent in conventional approaches.

Technology Category

• Cognitive Modeling & Cognitive Systems: Simulating Human Behavior
• Intelligent Robots: Manipulation
• Computer Vision: Low Level & Physics-based Vision

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems
• Responsible Web: Human-perceived consequences of algorithmic deployment on the web

Abstract

In this work we analyze and address a fundamental restriction that blocks the reliable application of codimensional yarn-level and shell models with thickness, to simulate real-world woven and knit fabrics. As discretizations refine toward practical and accurate physical modeling, such models can generate non-physical contact forces with stencil-neighboring elements in the simulation mesh, leading to severe locking artifacts. While not well-documented in the literature, this restriction has so far been addressed with two alternatives with undesirable tradeoffs. One option is to restrict the mesh to coarse resolutions, however, this eliminates the possibility of accurate (and consistent) resolution simulations across real-world material variations. A second alternative instead seeks to cull contact pairs that can create such locking forces in the first place. This relaxes resolution restrictions but compromise robustness. Culling can and will generate unacceptable and unpredictable geometric intersections and tunneling that destroys weaving and knitting structures and cause unrecoverable pull-throughs. We address these challenges to simulating real-world materials with a new and practical contact-processing model for thickened codimensional simulation, that removes resolution restrictions, while guaranteeing contact-locking-free, non-intersecting simulations. We demonstrate the application of our model across a wide range of previously unavailable simulation scenarios, with real-world material yarn and fabric parameters and patterns, challenging simulation conditions and mesh resolutions, and both rod and shell models, integrated with the IPC barrier.

Problem

• Simulating woven fabrics with thickness causes non-physical contact forces
• Existing methods either limit resolution or cause geometric intersections
• New contact model eliminates locking while preventing material intersections

Innovation

• Contact-processing model eliminates resolution restrictions
• Guarantees contact-locking-free non-intersecting simulations
• Practical thickened codimensional simulation for fabrics