Transferring visual representations pretrained on human videos to robot manipulation requires learning reliable correspondences between human and robot demonstrations. However, paired demonstrations can differ in execution rate and in the proportion of non-key frames that do not directly reflect task progress. Frames at the same relative timestamp may therefore represent different task stages, which can cause correspondence learning to fail. To address these issues, we propose Frame-Level Temporal Alignment (FLTA), a framework that uses two temporal priors to adapt visual encoders pretrained on human videos for robot manipulation. It learns shared task-progress representations without frame-level correspondence annotations, allowing frames at different relative temporal positions to match. A global progress prior combines normalized temporal positions with visual similarity to construct a soft correspondence target. A local temporal order prior penalizes backward transitions while allowing stays and varying forward rates to accommodate execution-rate differences. With ResNet-50 and ViT encoders, our method achieves relative improvements of 46.93% and 65.96%, respectively, over the best baselines in average simulation success rates and achieves higher task success rates on real-world manipulation tasks. These results also suggest that effective human-robot adaptation depends less on the number of parameters updated than on which parameters are selected. Our project page is available at https://rtx5090ultra.github.io/FLTA-Project-Page/.
Figures & tables
Figure 1: From video-level to frame-level alignment. Video-level alignment brings human and robot video representations closer without explicitly establishing frame-level correspondences. Differences in execution rates and the proportion of non-key frames mean that frames sampled at the same relative time may show different task stages. Our method addresses these temporal discrepancies by learning cross-domain frame correspondences without requiring frame-level annotations.
Figure 2: Overview of the proposed temporal alignment framework. Here, only the normalization-affine parameters of the visual encoder are updated. The auxiliary frame discrimination loss learns discriminative frame representations within each domain. The global progress prior D and visual similarity jointly construct soft correspondences. The local temporal order prior Q penalizes backward transitions while allowing stays and forward transitions of varying magnitudes. Numbered stages are shown only for illustration.
Figure 3: Simulated and real-world evaluation environments. Top: Level 1 and Level 2 unseen manipulation tasks from the AGNOSTOS benchmark in RLBench. Bottom: Four real-world tasks used on the Trossen WidowX AI Arm.
Encoder
Method
L1 ↑
L2 ↑
Avg. ↑
Encoder
Method
L1 ↑
L2 ↑
Avg. ↑
D4R-ViT
Frozen
8.31 (0.50)
11.60 (0.33)
9.74 (0.25)
DNCE-CLIP
Frozen
10.05 (1.24)
9.73 (1.32)
9.91 (1.14)
+ HRP
10.56 (1.67)
12.13 (0.38)
11.25 (1.03)
+ HRAlign ∗
12.62 (2.06)
9.47 (1.05)
11.25 (1.58)
+ Ours
18.05 (0.52)
19.47 (0.50)
18.67 (0.49)
+ Ours
15.38 (0.44)
16.13 (1.00)
15.71 (0.22)
(+70.93%)
(+60.51%)
(+65.96%)
(+21.87%)
(+70.33%)
(+39.64%)
R3M-RN50
Frozen
12.62 (0.25)
11.73 (0.50)
12.23 (0.36)
AcTOL-CLIP
Frozen
11.28 (1.53)
11.47 (0.19)
11.36 (0.82)
+ HRAlign
11.59 (1.62)
12.80 (0.33)
12.12 (0.78)
+ HRAlign ∗
11.90 (1.47)
12.27 (0.19)
12.06 (0.78)
Table 1: Zero-shot manipulation success rates (%) on the 23 unseen AGNOSTOS tasks, with standard deviations in parentheses. Avg. denotes the average over all 23 tasks. Bold indicates the best result within each initialization group. Green indicates relative gains over HRP for D4R-ViT and HRAlign for the other initializations. DNCE denotes DecisionNCE. ∗ denotes reproduced.
Method
T1
T2
T3
T4
Avg. ↑
Frozen
0.35
0.25
0.55
0.00
0.29
+ HRP
0.40
0.50
0.35
0.05
0.33
+ Ours
0.65
0.60
0.85
0.15
0.56
Table 2: Real-world success rates using D4R-ViT initialization. T1–T4 denote pick–place, press, push, and open, respectively.
In-distribution (RH20T)
Zero-shot (self-collected)
Setting
D4R-ViT
R3M-RN50
D4R-ViT
R3M-RN50
Frozen
15/100
14/100
42/100
36/100
+ HRP / HRAlign
17/100
22/100
47/100
43/100
+ Ours
39/100
43/100
56/100
61/100
Table 3: Human-to-robot task-progress retrieval, reported as correct retrievals out of 100 queries per evaluation setting. Higher is better.
Figure 4: Human-to-robot task-progress retrieval examples from RH20T (top) and the self-collected zero-shot data (bottom). Each row shows a human query and the nearest robot frames retrieved by Frozen R3M, HRAlign, and our method. Green checks indicate correct retrievals.
Variant
D
Q
LInfoNCE
D4R-ViT
R3M-RN50
L1 ↑
L2 ↑
Avg. ↑
L1 ↑
L2 ↑
Avg. ↑
Full
✓
✓
✓
18.05 (0.52)
19.47 (0.50)
18.67 (0.49)
16.82 (1.24)
19.47 (0.19)
17.97 (0.67)
w/o LInfoNCE
✓
✓
–
16.15 (0.66)
17.27 (1.15)
16.64 (0.54)
16.31 (0.50)
17.73 (0.19)
16.93 (0.22)
w/o D
–
✓
✓
14.56 (0.77)
18.53 (0.38)
16.29 (0.43)
15.69 (1.26)
17.07 (0.82)
16.29 (0.91)
w/o Q
✓
–
✓
13.74 (0.77)
17.87 (0.50)
15.54 (0.46)
13.13 (0.38)
17.47 (0.68)
15.01 (0.36)
w/o D & Q
–
–
✓
11.18 (0.29)
15.20 (0.65)
12.93 (0.33)
11.79 (0.52)
15.47 (0.38)
13.39 (0.38)
Table 4: Ablations and alternatives on the simulation. In the TCC and Soft-DTW variants, LTA is replaced by the corresponding alignment loss.
Figure 5: Data efficiency and adaptation strategies with R3M-RN50. (a) Overall average success rate across L1 and L2 versus the fraction of paired human–robot pre-training data. (b) Late-adapter (Ad.) versus BN-affine (BN) fine-tuning. Params.: trainable parameters; HRA: HRAlign. All success rates are in percent.
Appendix figures & tables13 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 6: Temporal differences in paired human–robot videos. Left: median Robot-to-Human execution-time ratio, with Human time normalized to 1. Right: mean proportion of non-key frames before action execution.
Symbol
Meaning
H,R
Paired human and robot videos.
fθ
Visual encoder with parameters θ ; only normalization-affine parameters are updated during adaptation.
A1,A2
Augmentation operators for the two branches.
qnX,knX
Representations of the same frame index n under the two augmentations, for domain X∈{H,R} .
T,∣T∣
Sampled temporal index set and number of sampled frames per video.
n,N
Frame-instance index and total number of sampled frames per domain.
Appendix
Table 5: Core notation used in the proposed method.
Configuration
ViT
RN50
Training iterations
40,000
40,000
Optimizer
AdamW
AdamW
Learning rate
7.5×10−5
1.0×10−4
Frames per domain
160
160
Sampled frames
8
8
Weight decay
0
0
Appendix
Table 6: Pretraining configurations for ViT and RN50.
Configuration
DecisionNCE-CLIP
AcTOL-CLIP
Training iterations
40,000
40,000
Optimizer
AdamW
AdamW
Learning rate
1.0×10−4
1.0×10−4
Frames per domain
160
160
Sampled frames
8
8
Weight decay
0
0
Appendix
Table 7: Pretraining configurations for DecisionNCE-CLIP and AcTOL-CLIP.
Figure 7: Effect of the number of sampled frames per video on the overall average success rate across L1 and L2 simulation tasks using R3M-RN50. Full denotes the default eight-frame configuration.
Configuration
ViT
RN50
Policy architecture
Modified RVT2
Stage 1 attention layers
8
Stage 2 attention layers
1
Attention dimension
512
Optimizer
LAMB
Base learning rate
5×10−5
Appendix
Table 8: Downstream policy training configurations.
Encoder
Method
Toilet
Knife
Fridge
Micro.
Laptop
Phone
Seat
Lamp Off
Lamp On
Book
Umb.
Grill
Bin
Avg.
Std.
D4R-ViT
Frozen
0
0
16.0
18.7
14.7
0
56.0
0
0
0
0
2.7
0
8.31
0.50
+ HRP
0
1.3
22.7
10.7
32.0
0
45.3
2.67
2.67
0
1.3
18.7
0
10.56
1.67
+ Ours
0
0
64.00
54.67
28.00
0
73.33
0
0
0
1.33
12.00
1.33
18.05
0.52
R3M-RN50
Frozen
0
1.3
29.3
32.0
13.3
0
73.3
1.3
1.3
1.3
0
10.7
0
12.62
0.25
+ HRAlign
0
0
37.3
14.7
24.0
0
65.3
6.7
1.3
0
0
1.3
0
11.59
1.62
+ Ours
0
6.67
64.00
33.33
46.67
0
61.33
1.33
0
0
0
5.33
0
16.82
1.24
Appendix
Table 9: Per-task success rates (%) on the 23 unseen AGNOSTOS tasks, averaged over three evaluation runs. Avg. reports the average success rate for each level, and Std. its standard deviation across runs. DNCE denotes DecisionNCE. ∗ denotes reproduced.
Figure 8: Human-to-robot task-progress retrieval examples from RH20T. Each row shows a human query and the nearest robot frames retrieved by Frozen R3M, HRAlign, and our method. Green checks indicate correct retrievals.
Figure 9: Human-to-robot task-progress retrieval examples from the self-collected zero-shot data. Each row shows a human query and the nearest robot frames retrieved by Frozen R3M, HRAlign, and our method. Green checks indicate correct retrievals. “None” denotes frames outside the annotated progress segments.
task_0015: S1: approach; S2: lift and aim; S3: striking; S4: return stick and release
task_0015
Human
0–43
44–69
44–47
47–55
55–64
64–69
task_0015
Robot
0–199
200–315
200–220
220–247
247–280
280–315
Appendix
Table 10: Frame annotations for the ten selected RH20T human–robot pairs. Each task has one human-robot pair. Stage names are task-specific.
Task
Demo
Domain
Outside
Annotated
S1
S2
S3
carrot: S1: approach; S2: lift and carry to pot; S3: release and retreat
carrot
001
Human
0–78; 155–164; 169–203
79–154; 165–168
79–119
119–154
165–168
carrot
001
Robot
247–299
0–246
0–155
155–226
226–246
carrot
002
Human
0–86; 169–203
87–168
87–113
113–156
156–168
carrot
002
Robot
253–299
0–252
0–142
142–232
232–252
carrot
003
Human
0–81; 174–218
82–173
82–108
108–157
157–173
Appendix
Table 11: Frame annotations for the four self-collected zero-shot tasks, with five human and five robot videos per task. Stage names are task-specific.
Split
# Tasks
Task categories
Training
18
Close jar; insert onto square peg; light bulb in; meat off grill; open drawer; place cups; place shape in shape sorter; place wine at rack location; push buttons; put groceries in cupboard; put item in drawer; put money in safe; reach and drag; slide block to color target; stack blocks; stack cups; sweep to dustpan of size; and turn tap.
Testing Level-1
13
Put toilet roll on stand; put knife on chopping board; close fridge; close microwave; close laptop lid; phone on base; toilet seat down; lamp off; lamp on; put books on bookshelf; put umbrella in umbrella stand; open grill; and put rubbish in bin.
Testing Level-2
10
Take USB out of computer; take lid off saucepan; take plate off colored dish rack; basketball in hoop; scoop with spatula; straighten rope; turn oven on; beat the buzz; water plants; and unplug charger.
Appendix
Table 12: Seen training and unseen testing task categories in the AGNOSTOS benchmark. The 23 testing categories are disjoint from the 18 training categories.
Figure 10: Real-world manipulation tasks evaluated using the Trossen WidowX AI arm.
The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China. · Zhejiang University, Hangzhou, China. · Simon Fraser University, Burnaby, BC, Canada. +1