ArtLLM: Generating Articulated Assets via 3D LLM

1ShanghaiTech University 2Tencent Hunyuan 3HKUST
Teaser

We propose ArtLLM, a novel framework capable of rapidly generating articulation assets from images or text. By using a 3D LLM to jointly predict part layouts and joints, and integrating state-of-the-art part generation methods, our approach can produce high-quality, physically grounded articulation assets.

Abstract

Creating interactive digital environments for gaming, robotics, and simulation relies on articulated 3D objects whose functionality emerges from their part geometry and kinematic structure. However, existing approaches remain fundamentally limited: optimization-based reconstruction methods require slow, per-object joint fitting and typically handle only simple, single-joint objects, while retrieval-based methods assemble parts from a fixed library, leading to repetitive geometry and poor generalization. To address these challenges, we introduce ArtLLM, a novel framework for generating high-quality articulated assets directly from complete 3D meshes. At its core is a 3D multimodal large language model trained on a large-scale articulation dataset curated from both existing articulation datasets and procedurally generated objects. Unlike prior work, ArtLLM autoregressively predicts a variable number of parts and joints, inferring their kinematic structure in a unified manner from the object's point cloud. This articulation-aware layout then conditions a 3D generative model to synthesize high-fidelity part geometries. Experiments on the PartNet-Mobility dataset show that ArtLLM significantly outperforms state-of-the-art methods in both part layout accuracy and joint prediction, while generalizing robustly to real-world objects. Finally, we demonstrate its utility in constructing digital twins, highlighting its potential for scalable robot learning.

Method

pipeline

Given an input point cloud, ArtLLM first predicts a tokenized articulation blueprint that specifies part layouts and kinematic structures. This blueprint then conditions a part-aware generative model to synthesize high-fidelity link geometries, followed by a physics-based joint-limit correction module refines the articulation, producing simulation-ready articulated assets.

physical_correction

When predicting joint limits, the model relies solely on the geometric state at a single timestep, which limits its abil ity to perceive dynamic motion. This can lead to inter-part collisions during articulation, thereby compromising phys ical realism. To address this issue, we introduce a post processing correction step that refines joint limits based on collision detection.

BibTeX

@inproceedings{wang2026artllm,
  title={ArtLLM: Generating Articulated Assets via 3D LLM},
  author={Wang, Penghao and Xie, Siyuan and Yan, Hongyu and Yang, Xianghui and Huang, Jingwei and Guo, Chunchao and Gu, Jiayuan},
  booktitle={Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition},
  pages={34281--34291},
  year={2026}
}