--- license: apache-2.0 tags: - robotics - lerobot - ur7e - cube-stacking --- # Cube stack — raw **Task:** `stack the red cube on the blue cube` UR7e/GELLO cube-stacking recordings collected on 2026-09-19. Place the red cube on top of the blue cube. ![First, middle and final scene-camera frames of the first take](assets/task_preview.jpg) This preview is extracted from `take_01_20260919_212809/cam1.mp4`; it is not a separate setup photograph or an outcome label. ## Contents 60 episodes / 20,177 cam1 master frames at 30 FPS (about 11.2 minutes). Two 1280×720 RGB cameras (cam1 scene, cam2 wrist); no depth. State/action each contain six joints plus gripper. Raw files remain unchanged under `raw//` in the raw repository. ## Collection tags Exact suffixes are preserved in `folder_tag` and `folder_labels` in source_takes.json. `recovery_label="recover"` selects all recovery variants, consistent with previous lighting releases. Counts: `{"untagged": 48, "recover": 9, "recover_many": 3}`. Original full take names are retained, including two different takes numbered 01. No take was excluded. Tags are collection annotations, not verified success/failure labels. No paper train/validation/test partition is assigned; the default LeRobot train range exposes the full corpus. ## Conversion Existing fixed-recorder recipe (`convert_takes_to_lerobot.py`, LeRobot 0.6.1/v3.0): camera/joint header `stamp_s` alignment, command/gripper callback `t_rel_s`, nearest timestamps, cam1 master grid. No servo-lag subtraction or frame dropping. State: ur_q1..6 + grip_pos; action: cmd1..6 + grip_cmd. GELLO leader coordinates are excluded from policy observations. Companion: [Bigenlight/cube_stack_lerobot_v3](https://huggingface.co/datasets/Bigenlight/cube_stack_lerobot_v3). Independent conversion validation: {'pass': 43, 'fail': 0, 'warn': 0, 'skip': 0, 'total': 43}. This validates conversion fidelity, not robot policy success.