Sichang0621/abc_fold_box_v21

ABC fold_the_paper_box — LeRobot v2.1

A LeRobot v2.1 conversion of the fold_the_paper_box task from XDOF/ABC-130k, prepared for fine-tuning pi0.5 (pi05_base) on the bimanual YAM platform.

Contents

Attribute	Value
Episodes	500 (first 500 of 2,387 train episodes, sorted by episode uuid)
Frames	2,260,990 (~21 hours)
FPS	30
Robot	Bimanual station, 2× 6-DoF YAM arms, parallel-jaw grippers
Cameras	head_camera, left_wrist_camera, right_wrist_camera — 640×480 h264
Task instruction	fold the paper box
Codebase version	LeRobot v2.1

State / action format

Both observation.state and action are 14-D float32:

[left_joint_0..5, left_gripper, right_joint_0..5, right_gripper]

• Joint values are absolute positions in radians, base → wrist.
• Gripper is the normalized aperture from ABC-130k (0 = closed, 1 = open).
• action holds the commanded joint positions (ABC /{side}-arm-action + /{side}-ee-action); observation.state holds the measured ones (/{side}-arm-state + /{side}-ee-state).
• Actions are absolute, not deltas. (openpi's pi0.5 recipe applies DeltaActions internally at train time.)

How this was converted

Source episodes are MCAP files. In ABC-130k the streams run on independent clocks — the action stream at ~200 Hz, state at ~265 Hz, cameras at 30–60 Hz depending on station type — so the conversion resamples everything onto a fixed 30 Hz tick clock using causal floor matching (the latest message at or before each tick), over the overlap window of all streams. This matches the tick rate used by the official ABC exporter.

Both station types present in the source are handled: RealSense (mono top camera) and ZED-X (stereo top camera, where one eye is picked deterministically per episode via sha1(episode_id) parity). All camera streams are letterboxed to 640×480 preserving aspect ratio.

Conversion script: convert_abc_mcap_to_lerobot_v21.py — scripts/convert_abc_mcap_to_lerobot_v21.py.

meta/episode_ids.json maps each episode_index back to its original ABC-130k episode uuid for traceability.

Usage

from lerobot.common.datasets.lerobot_dataset import LeRobotDataset

ds = LeRobotDataset("Sichang0621/abc_fold_box_v21")
print(ds.num_episodes, ds.num_frames, ds.fps)
item = ds[0]  # observation.state (14,), action (14,), 3× images (3,480,640)

Attribution and license

This dataset is derived from XDOF/ABC-130k (Apache-2.0), released alongside the ABC project (abc.bot, code). All robot trajectories and imagery originate from ABC-130k; this repository contributes only the format conversion described above. Please cite the ABC project when using this data.

Note that the upstream ABC-130k dataset is access-gated on the Hub. Licensed under Apache-2.0, consistent with the source.