README.md

---
license: cc-by-nc-4.0
tags:
  - digital-twin
  - usd
  - isaac-sim
  - lighting
pretty_name: Room 305 Digital Twin
---

# Room 305 Digital Twin

A USD digital twin of NYCU Room 305 (lighting scene), built by the **Human-centered Intelligent System Lab (hcislab)** — [GitHub @HCIS-Lab](https://github.com/HCIS-Lab). Authored for **NVIDIA Isaac Sim 5.1**.

**Lab links:** [GitHub @HCIS-Lab](https://github.com/HCIS-Lab) · [HF @hcislab](https://huggingface.co/hcislab)

## Contents

```
nycu_light_collider.usd    # main scene — open this in Isaac Sim (geometry + colliders + materials + lights)
nycu_lights.usdz           # referenced geometry + textures (center.jpg, Translucent_Glass_Tinted.jpg)
```

`nycu_light_collider.usd` references `nycu_lights.usdz` by a **relative** path, so the two files must stay side by side. `snapshot_download` keeps them together automatically.

Scene stats (loaded in Isaac Sim 5.1): 443 meshes (~188k points), 419 materials / 459 shaders, a `DomeLight` + `RectLight`. Approx extent 12.1 × 7.0 × 3.4 m.

## Usage

```python
from huggingface_hub import snapshot_download

path = snapshot_download(
    repo_id="hcislab/digital-twin",
    repo_type="dataset",
)
# open path/nycu_light_collider.usd in Isaac Sim 5.1
```

In Isaac Sim (Python):

```python
import omni.usd
omni.usd.get_context().open_stage(f"{path}/nycu_light_collider.usd")
```

## Notes

- Textures are bundled inside `nycu_lights.usdz` and resolve via relative paths — verified self-contained with `UsdUtils.ComputeAllDependencies`.
- Two references resolve **at runtime** in Isaac Sim / Omniverse and are intentionally not bundled:
  - `OmniGlass.mdl` — Omniverse stock material library.
  - A Cloudy dome-light HDR served from the Omniverse content CDN.
  Materials and dome lighting need an Omniverse asset connection / cache to display fully; geometry and the `RectLight` load without it.
- Verified to open cleanly in Isaac Sim 5.1 from a fresh download.

## Citation

If you use this digital twin, please cite it:

```bibtex
@misc{hcislab_room305_2026,
  title        = {Room 305 Digital Twin},
  author       = {{Human-centered Intelligent System Lab}},
  year         = {2026},
  howpublished = {Hugging Face dataset},
  url          = {https://huggingface.co/datasets/hcislab/digital-twin},
  note         = {NVIDIA Isaac Sim 5.1 USD digital twin}
}
```

A machine-readable `CITATION.cff` is included (Hugging Face renders a "Cite this" entry from it).

## License

**CC BY-NC 4.0** ([Creative Commons Attribution-NonCommercial 4.0](https://creativecommons.org/licenses/by-nc/4.0/)).

- ✅ Share and adapt for **non-commercial** research/education, **with attribution** (cite as above).
- ❌ **No commercial use** without separate permission from the lab. For commercial licensing, contact **hcislab01@gmail.com**.

Note: the referenced `OmniGlass.mdl` and dome-light HDR are NVIDIA Omniverse assets governed by their own licenses; they are not redistributed here.