Poke &Wiggle
Papers
Paper

Patch Policy (CLS versus Dense)

Patch Policy: Efficient Embodied Control via Dense Visual Representations

Claim tested: Dense patch features improve real-robot task success over CLS features from the same pretrained visual encoder.

Tested

Paper
arXiv⁠ (opens in a new tab)
Code
GitHub⁠ (opens in a new tab)
Venue
—
Authors
Gaoyue Zhou et al.
Farm tasks
4
Evaluation
360 episodes (180 for baseline, 180 for method)

Result

Improvement over baseline

Not replicated

Reported
+17 pts
Ours
+7 pts
−200+20+40+60
  • Gain vs baseline
  • 95% CI, −3 pts to +16 pts
  • Paper's reported gain
  • No difference

Success rate

Reported
82%
Ours
14%
0%20%40%60%80%100%
  • Measured on our stations
  • 95% CI, 9%–23%
  • Reported in the paper

Across iterations

  1. Iteration 1vs CLS token+7 pts
  2. Iteration 2vs CLS token+22 pts
−200+20+40+60

By task

TaskBaselineCLS tokenMethodPatch Policy (CLS versus Dense)Improvement
e01Clamp electrical component0%0/300%0/300 pts−11 to +11
e02Connect DC jack0%0/300%0/300 pts−11 to +11
e03Place spray bottles upright, nozzle forward (bimanual handover)23%7/3043%13/30+20 pts−4 to +41
All tasks8%7/9014%13/90+7 pts−3 to +16
Reported in the paper65%82%+17 pts

Rollouts

One clip per environment from this entry's evaluation, beside where each evaluation episode placed the environment's objects, coloured by its rating. Use the button beside each environment to open its evaluation dataset in the dataset viewer.

  1. e02Connect DC jack
  2. Held-out benchmark environment
    e01Clamp electrical component
  3. Held-out benchmark environment
    e03Place spray bottles upright, nozzle forward (bimanual handover)

Implementation Details

What we changed

We compare dense patch features with CLS features to test the paper’s claim that spatially detailed visual features improve manipulation success. Both policies use the same frozen DINOv2 ViT-S/14 encoder, a block-causal transformer and a VQ-BeT action head, and differ only in the visual tokens they read. This first round departs from the paper in the ways listed below, which later rounds brought closer to it.

  • Robot state input. Both arms receive the robot state on every token, while the paper’s policies receive visual inputs only.
  • Single observation frame. Both arms see only the current frame instead of the paper’s visual observation history.
  • Longer chunks. Both arms predict 32 steps instead of 5 or 10, about one second of motion at 30 Hz.

See the code changes on GitHub⁠ (opens in a new tab)

Prompt summary

Test whether dense patch features from a pretrained visual encoder improve real-robot success over CLS features from the same encoder. Implement the method and its control, choose 3 tasks, train in the cloud and evaluate on stations. (Implemented with frozen DINOv2 ViT-S/14, a block-causal transformer and a VQ-BeT head; one observation frame, robot state on every token, 32-step chunks.)

Response summary

SR 7.8% CLS vs 14.4% patch (+6.7 pp, p = 0.18, n.s.) and AP 19.6% vs 42.0% (+22.4 pp, p < 0.001); successes only on spray (7/30 vs 13/30), 0/30 for both arms on clamp and dc_jack.

Conclusion

Dense patches made far more progress but successes were too rare to call. Next: tighten the setup to the paper (images only, observation history, reactive replanning, larger tokenizer).