> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lancedb.com/llms.txt
> Use this file to discover all available pages before exploring further.

# LeRobotDataset

> Use Lance-backed LeRobotDataset loaders and LanceDB to inspect, filter, and train on robotics datasets from the Hugging Face Hub.

[LeRobot](https://huggingface.co/docs/lerobot/index) is Hugging Face's open-source robotics stack for collecting data, training policies, running simulations, and sharing robotics datasets and models on the Hub.

[LeRobotDataset v3.0](https://huggingface.co/docs/lerobot/lerobot-dataset-v3) standardizes robot learning data across sensorimotor time series, actions, multi-camera video, and task metadata. Its v3 layout stores high-frequency tabular signals in Parquet, visual streams as MP4 shards, and metadata that reconstructs episode-level views from larger files.

Lance pairs well with LeRobot when you need high-performance random access, lazy multimodal blob reads, and a single table interface for curation, search, and training data preparation. The `lerobot-lancedb` package ships Lance-backed `LeRobotDataset` subclasses, and LanceDB can open Lance-formatted LeRobot datasets on the Hub directly through `hf://` URIs.

## Install

```bash theme={"theme":{"light":"vitesse-light","dark":"catppuccin-mocha"}}
pip install lancedb lance lerobot-lancedb
```

## Use Lance-backed LeRobotDataset loaders

`LeRobotLanceDataset` is useful when your Lance-backed dataset stores decoded image observations. It's a drop-in replacement for `LeRobotDataset`, so existing policy training code keeps working with the usual PyTorch dataset and dataloader patterns.

<CodeBlock filename="Python" language="Python" icon="python">
  {PyFrameworksLerobotLancedbImageDataset}
</CodeBlock>

For datasets that store camera observations as MP4 video segments, use `LeRobotLanceVideoDataset` instead.

<CodeBlock filename="Python" language="Python" icon="python">
  {PyFrameworksLerobotLancedbVideoDataset}
</CodeBlock>

<Info>
  Use the image loader for Lance-backed repos that store image frames. Use the video loader for MP4-backed LeRobot datasets such as `lance-format/lerobot-pusht-lance`.
</Info>

## Open LeRobot Lance tables with LanceDB

Lance-formatted LeRobot datasets published by `lance-format` expose each `.lance` file under `data/` as a LanceDB table. The PushT dataset, for example, has `frames`, `episodes`, and `videos` tables.

<CodeBlock filename="Python" language="Python" icon="python">
  {PyFrameworksLerobotOpenLanceTables}
</CodeBlock>

Opening the tables directly is handy for inspecting schemas, counting rows, sampling metadata, or building curation workflows before any data reaches the training loop.

## Filter a frame window

Most robotics workflows want a deterministic slice by `episode_index`, `frame_index`, or task metadata long before training begins. LanceDB filters those rows without touching the video blobs.

<CodeBlock filename="Python" language="Python" icon="python">
  {PyFrameworksLerobotFilterFrames}
</CodeBlock>

With the filtered set in hand, you can materialize a smaller local LanceDB database, add derived columns, attach embeddings, or build vector and scalar indexes for faster repeated access.

## Example Lance-formatted LeRobot datasets

<CardGroup cols={2}>
  <Card title="LeRobot PushT" href="/datasets/lerobot-pusht">
    A Lance-formatted version of `lerobot/pusht` with frame, episode, and video tables.
  </Card>

  <Card title="LeRobot X-VLA Soft-Fold" href="/datasets/lerobot-xvla-soft-fold">
    A multi-camera robotics dataset packaged as Lance tables for frame-level and episode-level access.
  </Card>
</CardGroup>

## More resources

<CardGroup cols={2}>
  <Card title="LeRobotDataset v3.0" href="https://huggingface.co/docs/lerobot/lerobot-dataset-v3">
    Hugging Face's guide to the v3 dataset layout, streaming, transforms, and migration.
  </Card>

  <Card title="lerobot-lancedb" href="https://lancedb.github.io/lerobot-lancedb/">
    API documentation for the Lance-backed LeRobotDataset implementations.
  </Card>
</CardGroup>

## When to use each interface

| Interface                  | Best for                                                                                 |
| :------------------------- | :--------------------------------------------------------------------------------------- |
| `LeRobotDataset`           | Standard LeRobot training loops and policy code                                          |
| `LeRobotLanceDataset`      | Drop-in training on Lance-backed image datasets                                          |
| `LeRobotLanceVideoDataset` | Drop-in training on Lance-backed video datasets                                          |
| LanceDB                    | Interactive inspection, filtering, curation, search, indexing, and materializing subsets |
| `lance.dataset(...)`       | Lower-level schema, fragment, index, and blob access                                     |