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A list of all the posts and pages found on the site. For you robots out there, there is an XML version available for digesting as well.
Pages
About
About me
PhD Dissertation
Towards Realistic Real-Time Physics-Based Simulation
Posts
Rigid Body Dynamics with VBD, Section I: Free Bodies
Published:
In the VBD paper (SIGGRAPH 2024), we briefly discuss extending Vertex Block Descent to rigid body simulation. The idea is natural: instead of updating a single vertex with 3 DoF, you update an entire rigid body with 6 DoF. But the details matter. This post walks through the full derivation—from the continuous Newton-Euler equations, to discrete backward Euler as a nonlinear system, to the Schur complement solve you actually run each iteration—with reference code from Newton, which implements this approach under the name AVBD (Augmented VBD).
Implementing VBD Damping Properly
Published:
Vertex Block Descent (VBD) is a physics solver we published at SIGGRAPH 2024 for elastic body dynamics. It offers unconditional stability, excellent GPU parallelism, and fast convergence to implicit Euler solutions. While the paper covers the formulation comprehensively, actually implementing VBD correctly—especially the damping—turns out to be subtler than it first appears. This post discusses the key pitfalls and how to get them right, based on lessons learned during development with NVIDIA Warp.
Welcome to My Blog
Published:
Welcome to my blog! I’ll be sharing updates about my research and projects here.
portfolio
Gaia Engine
A C++ physics simulation engine featuring VBD and XPBD solvers, powerful mesh data structures, collision detection, and an extensible physics framework. 844+ GitHub stars.
Offset Geometric Contact (OGC)
A novel contact model for guaranteed penetration-free simulation of codimensional objects. SIGGRAPH Asia 2025.
Vertex Block Descent (VBD)
A block coordinate descent physics solver achieving numerical convergence with unconditional stability and exceptional GPU performance. SIGGRAPH 2024.
Motion Capture with Checkerboard Suit
Capturing over 1,000 unique points on the human body using standard cameras and passive lights. SIGGRAPH 2021.
MeshFrame
A lightweight, header-only C++ mesh processing framework with blazing fast performance, supporting triangular and tetrahedral meshes.
publications
Mesh Saliency Detection via Double Absorbing Markov Chain in Feature Space
Published in The Visual Computer, 2016
A mesh saliency detection approach using absorbing Markov chain that considers both background and foreground cues.
Recommended citation: Xiuping Liu, Pingping Tao, Junjie Cao, He Chen, Changqing Zou. (2016). "Mesh Saliency Detection via Double Absorbing Markov Chain in Feature Space." The Visual Computer.
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Online Knapsack Problem Under Concave Functions
Published in Frontiers in Algorithmics, 2016
An online algorithm for the knapsack problem under concave functions with improved competitive ratios.
Recommended citation: Xin Han, Ning Ma, Kazuhisa Makino, He Chen. (2016). "Online Knapsack Problem Under Concave Functions." Frontiers in Algorithmics.
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Normal Estimation via Shifted Neighborhood for Point Cloud
Published in Journal of Computational and Applied Mathematics, 2017
A fast and quality normal estimator based on neighborhood shift for point clouds.
Recommended citation: Junjie Cao, Anka He Chen, Jie Zhang, Yujiao Li, Xiuping Liu, Changqing Zou. (2017). "Normal Estimation via Shifted Neighborhood for Point Cloud." Journal of Computational and Applied Mathematics.
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Multi-Normal Estimation via Pair Consistency Voting
Published in IEEE Transactions on Visualization and Computer Graphics (TVCG), 2018
A unified definition for point cloud normal of feature and non-feature points, allowing feature points to possess multiple normals.
Recommended citation: Jie Zhang, Junjie Cao (co-first authors), Xiuping Liu, Anka He Chen, Bo Li, Ligang Liu. (2018). "Multi-Normal Estimation via Pair Consistency Voting." IEEE Transactions on Visualization and Computer Graphics.
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Capturing Detailed Deformations of Moving Human Bodies
Published in ACM Transactions on Graphics 40(4) [Proceedings of SIGGRAPH], 2021
A method to capture over 1,000 unique points on the human body using only standard cameras and passive lights. • PDF • Project
Recommended citation: Anka He Chen, Hyojoon Park, Kutay Macit, Ladislav Kavan. (2021). "Capturing Detailed Deformations of Moving Human Bodies." ACM Transactions on Graphics 40(4).
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Shortest Path to Boundary for Self-Intersecting Meshes
Published in ACM Transactions on Graphics 42(4) [Proceedings of SIGGRAPH], 2023
A method for efficiently computing the exact shortest path to the boundary of a mesh from a given internal point in the presence of self-intersections. • Project • Video
Recommended citation: Anka He Chen, Elie Diaz, Cem Yuksel. (2023). "Shortest Path to Boundary for Self-Intersecting Meshes." ACM Transactions on Graphics 42(4).
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Vertex Block Descent
Published in ACM Transactions on Graphics 43(4) [Proceedings of SIGGRAPH], 2024
A block coordinate descent solution for the variational form of implicit Euler through vertex-level Gauss-Seidel iterations. • PDF • Project • Video
Recommended citation: Anka He Chen, Zhiheng Liu, Yin Yang, Cem Yuksel. (2024). "Vertex Block Descent." ACM Transactions on Graphics 43(4).
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Isaac Lab: A Unified and Modular Framework for Robot Learning
Published in arXiv preprint, 2025
A GPU-accelerated simulation framework for multi-modal robot learning built on NVIDIA Isaac Sim. • PDF • Project • GitHub
Recommended citation: Mayank Mittal, Pascal Roth, James Tigue, Antoine Richard, Octi Zhang, Peter Du, Antonio Serrano-Muñoz, Xinjie Yao, René Zurbrügg, Nikita Rudin, et al. (2025). "Isaac Lab: A Unified and Modular Framework for Robot Learning." arXiv preprint arXiv:2511.04831.
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Offset Geometric Contact
Published in ACM Transactions on Graphics 44(4) [Proceedings of SIGGRAPH Asia], 2025
A novel contact model for guaranteed penetration-free simulation of codimensional objects with minimal computational overhead. • PDF • Project • Video
Recommended citation: Anka He Chen, Jerry Hsu, Ziheng Liu, Miles Macklin, Yin Yang, Cem Yuksel. (2025). "Offset Geometric Contact." ACM Transactions on Graphics 44(4).
Download Paper
talks
Talk 1 on Relevant Topic in Your Field
Published:
This is a description of your talk, which is a markdown file that can be all markdown-ified like any other post. Yay markdown!
Conference Proceeding talk 3 on Relevant Topic in Your Field
Published:
This is a description of your conference proceedings talk, note the different field in type. You can put anything in this field.
teaching
Teaching experience 1
Undergraduate course, University 1, Department, 2014
This is a description of a teaching experience. You can use markdown like any other post.
Teaching experience 2
Workshop, University 1, Department, 2015
This is a description of a teaching experience. You can use markdown like any other post.