---
tags:
- lerobot
- so101
- molmoact2
---

# move_blue_ball_training_v21

This is a convention-converted copy of `andlyu/move_blue_ball_training`.

Only the 6D SO101 joint columns were changed:

- `observation.state`
- `action`

The source dataset was recorded with LeRobot SO101 v3 calibrated robot degrees.
This copy converts those joint vectors into the older SO100/SO101 v2.1 policy
degree convention expected by `allenai/MolmoAct2-SO100_101`.

Conversion:

```text
old = (new - [0, 90, -90, 0, 0, 0]) / [1, -1, 1, 1, 1, 1]
```

Equivalent per-joint form:

```text
shoulder_lift_old = 90 - shoulder_lift_new
elbow_flex_old    = elbow_flex_new + 90
```

All videos, task metadata, timestamps, frame indices, and episode boundaries are
copied from the source dataset. Global and per-episode LeRobot stats were
recomputed for the converted joint columns.