UniPhysGen-1.7B-Init

UniPhysGen-1.7B-Init

UniPhysGen-1.7B-Init is the training initialization checkpoint for UniPhysGen, a unified 3D model for grounding articulation semantics and intrinsic physical properties. It combines the Qwen3-1.7B language backbone with the Sonata point-cloud encoder and the UniPhysGen multimodal projection layers.

This checkpoint contains no UniPhys task-specific grounding training. It is intended as the starting point for physical semantic alignment and subsequent task-specific fine-tuning. It is not a recommended inference checkpoint.

Model details

Intended use

Use this checkpoint to reproduce the physical semantic alignment stage or to train UniPhysGen on compatible custom data. For released predictions, use one of the task-specific checkpoints instead:

• UniPhysGen-1.7B-Physics
• UniPhysGen-1.7B-Kinematics
• UniPhysGen-1.7B-Structure
• UniPhysGen-1.7B-Object

Installation

The model has been tested on Linux with Python 3.11, PyTorch 2.4.1, CUDA 12.4, and transformers==4.51.0.

[!IMPORTANT] Use transformers==4.51.0. This is the tested version and is pinned by the UniPhysGen project metadata.

git clone https://github.com/breezexian/UniPhysGen.git
cd UniPhysGen/uniphysgen

conda create -n uniphysgen python=3.11 -y
conda activate uniphysgen
conda install -y -c nvidia/label/cuda-12.4.0 cuda-toolkit

python -m pip install torch==2.4.1 torchvision==0.19.1 torchaudio==2.4.1 --index-url https://download.pytorch.org/whl/cu124
python -m pip install -e ".[train]"
bash scripts/install_cuda_extensions.sh

For inference only, replace python -m pip install -e ".[train]" with python -m pip install -e ..

The model uses a custom Transformers architecture. Install the UniPhysGen package before loading the checkpoint so that the custom configuration and model classes are registered.

Download and training

hf download breezexian/UniPhysGen-1.7B-Init \
  --local-dir checkpoints/UniPhysGen-1.7B-Init

Set the initialization path in the semantic-alignment release config:

model_name_or_path: checkpoints/UniPhysGen-1.7B-Init

Then launch the training entry point documented in the main project README. The corresponding training dataset is breezexian/UniPhys-40K.

Limitations

• This checkpoint is an initialization artifact and has not been fine-tuned for any of the four released grounding tasks.
• It should not be used as a drop-in text-generation model or with a generic Hugging Face text-generation pipeline.
• Inputs must follow the UniPhysGen point-cloud and prompt conventions.
• Model outputs may be inaccurate and require task-specific fine-tuning and validation before use in simulation or robotics.

License

The model weights are released under the Creative Commons Attribution-NonCommercial 4.0 International license. Commercial use is not permitted under this license. The UniPhysGen source code is licensed separately under Apache-2.0.

This checkpoint is derived from Qwen3-1.7B, released under Apache-2.0, and the official Sonata pretrained weights, released under CC BY-NC 4.0. See the included license for attribution details.

Citation

@article{li2026uniphysgen,
  title   = {UniPhysGen: Unified Physical Grounding for Simulation-Ready 3D Assets},
  author  = {Li, Xian and Wei, Rong and Yang, Lujie and Huang, Haolin and Fang, Junyuan and Tang, Siliang and Xiao, Jun and Tang, Rui and Li, Juncheng},
  journal = {arXiv preprint arXiv:2607.13586},
  year    = {2026}
}