InternDataTac/README.md

# InternDataTac H-Tac Release Sample

This directory contains the InternDataTac MANO tactile subsets included in this release.

Episode ids, task ids, parquet paths, and video paths are local to this release package.

## Subset Summary

| subset | episodes | frames | videos |
| --- | ---: | ---: | ---: |
| `curated__genie1_mano_tactile` | 49 | 7,553 | 49 |
| `curated__lift2_mano_tactile` | 35 | 6,351 | 35 |

The column schema and field meanings match the original InternDataTac release. See each subset's `meta/features.json` and `meta/dataset_info.json` for machine-readable schema details.

## Schema Consistency

Both InternDataTac subsets share the same 40-column per-frame schema:

- `curated__genie1_mano_tactile`
- `curated__lift2_mano_tactile`

Common frame fields are documented in the top-level `README.md`. This file lists InternDataTac-specific fields and metadata.

## Loading Notes

- Both InternDataTac subsets share one per-frame schema.
- Read `meta/features.json` before selecting parquet columns.
- Use `meta/tasks.jsonl` to resolve `task_index`.
- Use `meta/episodes.parquet` for episode length, task text, `robot_type`, parquet path, and video path.
- `mask.right_arm` and `mask.left_arm` mark inactive sides.
- Tactile and gripper values of `-1` on masked sides are missing values, not valid zero readings.
- Resolve `video.top_view` relative to the subset root.

## InternDataTac-Specific Per-Frame Fields

InternDataTac adds robot-gripper, arm-mask, and MANO tactile fields on top of the common schema.

| field | dtype / shape | meaning |
| --- | --- | --- |
| `state.right_gripper` | `float32[1]` | Right gripper openness/state, declared range `[0, 1]`. Masked inactive values are stored as `-1`. |
| `state.left_gripper` | `float32[1]` | Left gripper openness/state, declared range `[0, 1]`. Masked inactive values are stored as `-1`. |
| `action.right_gripper` | `float32[1]` | Right gripper action target, declared range `[0, 1]`. |
| `action.left_gripper` | `float32[1]` | Left gripper action target, declared range `[0, 1]`. |
| `mask.right_arm` | `bool` scalar | Right-arm inactive-side flag. `true` means this side is inactive/masked for that episode. |
| `mask.left_arm` | `bool` scalar | Left-arm inactive-side flag. `true` means this side is inactive/masked for that episode. |
| `tactile.right_mano_tactile` | `float32[351]` | Right-side MANO compact tactile pressure vector. |
| `tactile.left_mano_tactile` | `float32[351]` | Left-side MANO compact tactile pressure vector. |
| `tactile_pred.right_mano_tactile` | `float32[351]` | Right-side predicted or processed MANO tactile vector. |
| `tactile_pred.left_mano_tactile` | `float32[351]` | Left-side predicted or processed MANO tactile vector. |

## Tactile Representation

The tactile representation is `MANO compact 351 pressure`. Contact pressure is projected onto a shared MANO hand surface and stored as a 351-D compact vector.

Normalization is recorded in each subset's `meta/dataset_info.json` and `meta/episode_records/*.json`:

| subset | normalization method | scale |
| --- | --- | ---: |
| `curated__genie1_mano_tactile` | `dataset_robot_max` | `5914047.0` |
| `curated__lift2_mano_tactile` | `dataset_robot_max` | `15187778.0` |

Valid nonnegative tactile values are divided by the scale. Masked inactive-arm values remain `-1`; do not interpret `-1` as a physical zero-contact reading.

## Arm Masks And Missing Side Policy

InternDataTac episodes are usually single-arm tasks even though both left and right fields are present. The inactive side is preserved in the schema but filled with masked values.

Use both the frame-level mask fields and the episode record:

- Frame columns: `mask.right_arm`, `mask.left_arm`
- Episode metadata: `meta/episodes.parquet` columns `right_arm_mask`, `left_arm_mask`
- Per-episode metadata record: `meta/episode_records/episode_*.json` under `mask`, `pressure`, and `derived_eef_pose`

In the episode record, `active_arm` names the active side. A side with `missing_policy: static_arm_masked` has no pressure cache and is filled with `-1`.

## Episode Metadata

Each subset's `meta/episodes.parquet` has the same InternDataTac episode-level columns:

| field | meaning |
| --- | --- |
| `episode_index` | Episode id within the release subset. |
| `session_name`, `session_dir` | Release-local episode/session identifiers. |
| `length` | Number of frames in the episode. |
| `task_index`, `task` | Task id and task instruction. |
| `robot_type` | Robot family, such as `genie1` or `lift2`. |
| `fps` | Nominal frame rate, `30.0`. |
| `video.top_view` | Relative top-view video path when available. |
| `parquet_path` | Relative path to the episode parquet file. |
| `right_arm_mask`, `left_arm_mask` | Episode-level inactive-arm mask flags. |

## Video Availability

`curated__genie1_mano_tactile` and `curated__lift2_mano_tactile` include top-view MP4 files for every episode in this release.

## Release Files

Each Intern subset contains:

- `data/episode_*.parquet`: frame-level data.
- `meta/features.json`: 40-field per-frame schema.
- `meta/dataset_info.json`: dataset counts, modality mapping, coordinate systems, and tactile normalization.
- `meta/episodes.parquet`: episode-level index.
- `meta/tasks.jsonl`: task mapping.
- `meta/episode_records/*.json`: detailed per-episode metadata records.
- `videos/video.top_view/episode_*.mp4`: top-view MP4 videos for each episode.