Understanding how humans interact with the world requires a representation of physical interactions at the hand surface. Tactile sensing captures these interactions, but collecting tactile data at scale requires specialized hardware. We introduce TactoHand, a model that predicts three dense hand-surface interaction fields---contact, proximity, and 3D force---from monocular video. We derive geometry-based contact and proximity labels and motion-derived force labels from eligible training data within a curated collection spanning approximately 50 million source frames. TactoHand uses a temporal transformer to aggregate visual evidence across frames, while three learned queries decode the corresponding hand-surface fields. A differentiable physics layer further constrains force predictions using observed object motion. Across in-domain and out-of-domain benchmarks, TactoHand improves contact and proximity estimation over prior methods. In addition, physics supervision reduces position and rotation errors in motion rollouts, and the predicted contact and proximity fields improve downstream hand-object reconstruction. Together, these results show a scalable, low-cost path to learning hand-surface interaction fields without collecting tactile measurements. Code will be released at https://github.com/zhenqis123/Tactohand.
Figures & tables
Figure 1: Overview of TactoHand. A shared video encoder extracts frame-level features, aggregated by a temporal transformer. Three learned queries decode the contact, proximity, and 3D force interaction fields at corresponding MANO vertices. Predicted vertex forces are aggregated into an object-level wrench for differentiable rigid-body supervision. Contact, proximity, force, and pose losses are applied according to the supervision available for each sample.
Figure 2: Contact-label construction: normal filtering (left) and inside-mesh inclusion (right).
Figure 3: Force allocation geometry and weighting. Upper left: a local polyhedral friction cone constrains each active vertex force. Upper right: signed distance s distinguishes penetrated ( s<0 ), contacting ( s=0 ), and separated ( s>0 ) vertices. Lower left: vertex-local force directions on the hand surface. Lower right: the penalty weight (q(s)2+ϵ)−1 rises toward the relaxed 20 mm candidate cut-off.
Figure 4: Differentiable rigid-body supervision. Indices i,i+1,i+2 are 10 Hz image timestamps; each transition contains three 30 Hz force intervals. Predicted vertex forces determine the object wrench at the image-aligned interval, while the two intermediate intervals use detached motion-derived reference forces. Pose errors supervise the propagated state.
Proximity
Contact
Dataset
Method
ADE ↓
ADE-100 ↓
Accel. ↓
Method
P ↑
R ↑
Macro-F1 ↑
Micro-F1 ↑
HOCap ‡
InterField-SF
132.51
38.15
1.06
HACO
11.1
77.7
18.0
19.5
InterField-LSTM
134.69
40.10
0.47
EgoPHI
10.3
37.3
11.4
16.2
Ours (SF)
46.09
6.35
1.35
Ours (SF)
68.9
57.7
50.1
62.8
Ours (T)
42.51
6.40
1.07
Ours (T)
68.8
60.6
50.5
64.5
ARCTIC (s05, ego)
InterField-SF
29.65
9.81
0.82
HACO
42.2
82.2
42.2
55.8
Table 1: Proximity (left) and contact (right). ADE is in mm, Accel. in m/s 2 , and P/R/F1 in percent. ADE-100 clips predictions and targets at 100 mm; Macro-F1 averages F1 over frame–hand pairs with ground-truth or predicted contact. Bold marks the best per dataset. ‡ HOCap is excluded from training. See Appendix D for metrics.
Figure 5: Contact comparison showing the input scene, hand crop, predicted contact maps, and geometry-derived reference.
Model
Physics
Vertex MAE ↓
Active MAE ↓
Force angle ↓
Rollout ADE ↓
Rollout angle ↓
SF
Off
12.6
124.9
28.2
5.3
45.5
SF
On
12.9
126.7
29.8
3.8
27.4
T
Off
13.7
126.4
31.0
5.7
45.2
T
On
12.8
122.7
27.5
3.3
29.4
Table 2: Force and rollout ablation on DexYCB (DINOv3 ViT-L). SF/T: single-frame/temporal; MAE: mN; rollout ADE: cm; angles: degrees. Active targets exceed 0.05 N. The 0.4 s rollout uses reference-assisted intervals and excludes divergent windows (Appendix D.3 ); bold indicates column minima.
PA-VPE ↓
CDho↓
Dataset
Method
Base
+ HACO
+ Ours
Base
+ HACO
+ Ours
DexYCB
EasyHOI
9.937
9.516
9.077
24.140
12.552
2.004
ArtHOI
7.317
6.027
4.626
11.587
13.627
1.431
HOCap
EasyHOI
9.179
9.051
7.592
59.416
68.943
11.461
ArtHOI
6.984
6.684
6.073
5.234
5.199
1.104
MOW
EasyHOI
14.832
14.276
13.939
69.080
72.638
15.266
Table 3: Controlled reconstruction refinement. PA-VPE: mm; CDho : bidirectional mean squared hand–object Chamfer in 10−3m2 . Bold marks each method–dataset best.
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
Dataset
Sequences
Frames
Force labels: articulated objects
ARCTIC ( Fan et al., 2023 )
300
1 903 869
HOI4D ( Liu et al., 2022 )
2 973
891 900
Force labels: rigid objects
GigaHands † ( Fu et al., 2025 )
1 424
9 449 724
Show3D ( Rim et al., 2026 )
1 682
6 931 884
Appendix
Table 4: Data sources and labels in the curated collection.
Figure 6: Comparison of contact labels generated by HACO’s distance-only rule and our geometric rule. Normal filtering removes back-facing false positives, while inside-mesh inclusion recovers penetrating vertices missed by distance thresholding.
Methods
PA-VPE ↓
PA-JPE ↓
CDho↓
F-5ho↑
F-10ho↑
ACC ↓
DexYCB
EasyHOI
9.937
10.483
24.140
0.3609
0.5359
–
EasyHOI + HACO
9.516
10.032
12.552
0.3609
0.5392
–
EasyHOI + Ours
9.077
9.559
2.004
0.3817
0.5606
–
ArtHOI
7.317
7.520
11.587
0.3930
0.5240
4311.6
ArtHOI + HACO
6.027
6.190
13.627
0.3970
0.5300
3978.9
Appendix
Table 5: Full reconstruction results. PA-VPE/JPE: mm; CDho : 10−3m2 ; F-5/F-10: 5/10 mm; ACC: mm/s2 . Bold marks the best per method–dataset block; shading highlights PA-VPE and CDho .
Figure 7: HOCap ( Wang et al., 2025 ) reconstructions. Red circles highlight hand–object contact artifacts in the HACO variants.
Figure 8: EasyHOI ( Liu et al., 2025 ) reconstruction ablation. + Contact: contact-normal term; + Proximity: distance term; + Both: both terms. Values are per-example PA-VPE (mm).
Setting
Value
Hardware and batch
One node with eight A800 GPUs; 7 samples per GPU; two accumulation steps (112 samples per update)
Optimizer
AdamW; learning rate 2×10−5 for backbone and heads; weight decay 10−4 ; cosine decay with two-epoch warmup
Window sampling
32 frames, stride 32; each epoch samples 20% of the windows allocated to each dataset