One-Step Flow Policy: Self-Distillation for Fast Visuomotor Policies
Organizations: CSE Department, University of Michigan · Lehigh University · College of AI, Tsinghua University
Abstract
Generative flow and diffusion models provide the continuous, multimodal action distributions needed for high-precision robotic policies. However, their reliance on iterative sampling introduces severe inference latency, degrading control frequency and harming performance in time-sensitive manipulation. To address this problem, we propose the One-Step Flow Policy (OFP), a from-scratch self-distillation framework for high-fidelity, single-step action generation without a pre-trained teacher. OFP unifies a self-consistency loss to enforce coherent transport across time intervals, and a self-guided regularization to sharpen predictions toward high-density expert modes. In addition, a warm-start mechanism leverages temporal action correlations to minimize the generative transport distance. Evaluations across 56 diverse simulated manipulation tasks demonstrate that a one-step OFP achieves state-of-the-art results, outperforming 100-step diffusion and flow policies while accelerating action generation by over . We further integrate OFP into the model on RoboTwin 2.0, where one-step OFP surpasses the original 10-step policy. These results establish OFP as a practical, scalable solution for highly accurate and low-latency robot control.
Figures & tables
| Method | NFE | Door | Hammer | Pen | Bucket | Faucet | Laptop | Toilet | Average |
|---|---|---|---|---|---|---|---|---|---|
| DP | 100 | 51.7 4.0 | 100.0 0.0 | 67.7 1.2 | 34.7 4.7 | 38.7 1.5 | 80.3 2.9 | 76.0 1.7 | 64.2 2.3 |
| DP | 10 | 44.7 1.5 | 100.0 0.0 | 66.7 1.5 | 32.7 4.0 | 35.0 2.6 | 81.0 2.6 | 66.0 3.6 | 60.9 2.3 |
| FM Policy | 100 | 63.7 2.1 | 100.0 0.0 | 69.7 2.1 | 31.7 1.2 | 40.7 2.3 | 84.7 2.5 | 79.7 1.5 | 67.2 1.7 |
| FM Policy | 10 | 61.3 3.2 | 97.3 3.1 | 64.7 3.8 | 27.7 2.3 | 32.7 3.8 | 87.0 1.7 | 77.3 1.5 | 64.0 2.8 |
| CP | 1 | 46.3 3.5 | 100.0 0.0 | 58.7 5.7 | 30.7 2.5 | 33.3 0.6 | 79.0 2.6 | 69.7 3.1 | 59.7 2.6 |
| OneDP | 1 | 53.3 5.1 | 100.0 0.0 | 64.7 1.5 | 32.7 1.2 | 40.0 1.7 | 76.3 2.9 | 76.3 2.3 | 63.3 2.1 |
| Method | NFE | Adroit (3) | DexArt (4) | MetaWorld Easy (28) | MetaWorld Medium (11) | MetaWorld Hard (5) | MetaWorld Very Hard (5) | Average |
|---|---|---|---|---|---|---|---|---|
| DP3 | 100 | 79.0 0.6 | 63.7 0.6 | 82.8 8.0 | 46.5 3.8 | 38.3 9.6 | 41.0 0.6 | 66.4 5.7 |
| DP3 | 10 | 76.0 3.3 | 61.5 0.9 | 80.8 2.1 | 46.2 1.4 | 36.3 8.2 | 45.3 5.7 | 65.2 2.8 |
| FM Policy | 100 | 83.3 0.7 | 61.7 4.2 | 68.9 5.7 | 42.3 3.8 | 43.6 3.4 | 47.7 4.5 | 59.8 4.6 |
| FM Policy | 10 | 80.3 1.8 | 60.5 4.5 | 66.7 7.7 | 41.3 7.4 | 40.3 7.2 | 46.7 7.6 | 57.9 7.0 |
| CP | 1 | 76.3 4.6 | 60.7 3.4 | 68.3 1.8 | 32.1 4.3 | 28.7 5.2 | 36.0 2.3 | 54.7 2.9 |
| OneDP | 1 | 77.3 1.8 | 62.5 4.1 | 77.7 0.5 | 39.6 9.2 | 38.7 4.4 | 41.7 1.6 | 62.4 3.0 |
| Method | NFE | Bucket | Faucet | Laptop | Toilet | Average |
|---|---|---|---|---|---|---|
| OneDP | 1 | 32.7 5.8 | 44.7 3.1 | 89.3 3.8 | 83.3 3.8 | 62.5 4.1 |
| CP | 1 | 29.3 3.5 | 44.3 3.8 | 86.7 2.5 | 82.3 3.8 | 60.7 3.4 |
| 4 | 38.3 4.2 | 43.7 1.2 | 90.0 3.5 | 84.7 2.9 | 64.2 2.9 | |
| OFP | 1 | 39.3 0.6 | 45.7 3.8 | 91.7 3.2 | 81.3 3.2 | 64.5 2.7 |
| 4 | 42.7 2.1 | 47.0 1.0 | 92.3 4.2 | 83.0 1.7 | 66.2 2.2 |
Appendix figures & tables6 assets
Supplementary material from the paper’s appendix.
Appendix
| Method | NFE | Adroit | DexArt | |||||
|---|---|---|---|---|---|---|---|---|
| Hammer | Door | Pen | Laptop | Faucet | Bucket | Toilet | ||
| DP3 | 100 | 100 0 | 70 1 | 67 1 | 94 1 | 44 1 | 34 1 | 82 1 |
| DP3 | 10 | 98 2 | 66 4 | 64 4 | 91 1 | 43 1 | 35 1 | 77 1 |
| FM Policy | 100 | 100 0 | 76 1 | 74 1 | 92 5 | 39 4 | 32 3 | 83 4 |
| FM Policy | 10 | 100 0 | 72 3 | 69 3 | 92 3 | 37 5 | 34 5 | 80 7 |
| CP | 1 | 98 3 | 67 5 | 65 5 | 87 3 | 44 4 | 29 4 | 82 4 |
| Method | NFE | MetaWorld Easy | MetaWorld Medium | ||||
|---|---|---|---|---|---|---|---|
| Reach | Window | Window | Peg Unplug | Basket | Bin | ||
| Wall | Close | Open | Side | ball | Picking | ||
| DP3 | 100 | 62 14 | 100 0 | 87 7 | 90 11 | 100 0 | 19 3 |
| DP3 | 10 | 57 2 | 100 0 | 81 10 | 91 3 | 100 0 | 17 5 |
| FM Policy | 100 | 24 8 | 100 0 | 84 7 | 67 15 | 100 0 | 17 6 |
| FM Policy | 10 | 20 11 | 100 0 | 77 16 | 62 14 | 100 0 | 16 9 |
| Method | NFE | Adjust | Beat Block | Handover | Place Empty |
|---|---|---|---|---|---|
| Bottle | Hammer | Mic | Cup | ||
| 10 | 96.0 4.0 | 88.3 3.8 | 90.7 1.2 | 91.0 3.0 | |
| CFM | 1 | 85.3 3.1 | 82.0 3.6 | 74.3 1.2 | 74.7 2.9 |
| Shortcut | 1 | 89.3 2.3 | 78.0 3.6 | 75.0 3.0 | 81.3 2.5 |
| iMF | 1 | 92.7 2.3 | 84.3 2.5 | 82.7 2.9 | 87.0 3.5 |
| OFP | 1 | 99.0 1.0 | 91.7 2.5 | 94.3 3.8 | 93.7 1.5 |
| Method | NFE | Door | Hammer | Pen | Bucket | Faucet | Laptop | Toilet | Average |
|---|---|---|---|---|---|---|---|---|---|
| SCT | 1 | 72 3 | 100 0 | 68 5 | 33 3 | 42 1 | 89 1 | 77 1 | 68.7 |
| 4 | 82 1 | 100 0 | 72 2 | 36 2 | 44 3 | 90 0 | 82 1 | 72.3 | |
| SCT+SGR | 1 | 77 4 | 100 0 | 73 3 | 37 1 | 44 0 | 90 1 | 79 2 | 71.4 |
| 4 | 82 3 | 100 0 | 73 1 | 39 3 | 43 1 | 90 2 | 81 0 | 72.6 | |
| OFP | 1 | 79 7 | 100 0 | 76 7 | 39 0 | 46 4 | 92 3 | 81 3 | 73.3 |
| 4 | 86 2 | 100 0 | 79 1 | 43 2 | 47 1 | 92 4 | 83 1 | 75.7 |