# t000__ep013__blocks

- **suite / variant:** `` / ``
- **instruction:** Stack the yellow block on the wooden block
- **success:** False
- **control steps:** 1610  (31.9s at 50 Hz)
- **policy inferences:** 275  (replan_steps=6)
- **video:** `blocks/ep013/rollout.mp4`
- **features:** `275` prefix tensors (`prefix`; model=``)

## Semantic timeline

| seconds | control_step | policy_step | phrase |
|---|---|---|---|
| 0.0–3.0 | 0–150 | 0–25 | approaching yellow block |
| 3.0–6.0 | 151–301 | 25–50 | grasping and lifting yellow block |
| 6.0–9.0 | 302–452 | 50–75 | moving yellow block over wooden block |
| 9.0–12.0 | 453–603 | 75–100 | lowering yellow block onto wooden block |
| 12.0–15.0 | 604–754 | 100–125 | holding yellow block on wooden block |
| 15.0–18.0 | 755–905 | 125–150 | adjusting gripper on yellow block |
| 18.0–21.0 | 906–1056 | 151–176 | attempting release on wooden block |
| 21.0–24.0 | 1057–1207 | 176–201 | shifting position over wooden block |
| 24.0–27.0 | 1208–1358 | 201–226 | knocking yellow block off wooden block |
| 27.0–30.0 | 1359–1509 | 226–251 | idle near displaced yellow block |
| 30.0–31.9 | 1510–1609 | 251–268 | idle near objects |

## Failure

- **yes**
- **onset type:** obvious_mistake
- **onset:** 22.400793650793652 s (00:22.4)
- **frame / control_step:** 1129 (policy_step=188, chunk_index=1)
- **coarse onset:** 25.0 s (refined=True)
- **mode:** placement_or_insertion_failure
- **reason:** While attempting to place the yellow block on the wooden block, the robot failed to release the block cleanly and pushed it off the wooden block onto the table.
  Summary: improper release alignment; block knocked off target
- **recovery:** Re-grasp the yellow block from the tabletop, align it over the wooden block, and place it stably on top.
  Summary: re-grasp yellow block; place on wooden block
- **prevention:** Align the yellow block directly over the center of the wooden block and fully open the gripper before lifting away to prevent dragging or knocking the block.
  Summary: align yellow block squarely; release cleanly before retracting
- **justification:** The robot successfully picked up the yellow block and brought it over the wooden block. However, around 25.0 seconds, during the release phase, the gripper dragged and knocked the yellow block off the wooden block onto the table surface, resulting in a placement failure.