Organizations: Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Hong Kong, China · Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong, China · Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen, China
Grasping is a foundational capability in robotic manipulation. Scene-level 6-DoF grasp synthesis relies on point clouds for metric geometry, yet real-world point observations are often noisy, incomplete, and over-smoothed. RGB images provide object-region, boundary, and appearance cues, yet two bottlenecks limit their effective use in scene representation and local grasp reasoning. We present MMGNet, a Multi-Modal Grasp Synthesis Network that addresses these bottlenecks through hierarchical image-to-3D feature injection and rotational graspness modeling. Hierarchical injection integrates multi-scale image features throughout 3D representation formation, while the rotational graspness jointly predicts the grasp approach direction and in-plane rotation before organizing local image-informed features through grasp-shaded grouping. Ablation studies show that these two modules provide complementary gains. MMGNet achieves a mean AP of 60.34 on GraspNet-1Billion with RealSense, surpassing all compared methods. In real-world experiments with adversarial grasp objects, MMGNet improves the grasp success rate over AnyGrasp by 8.46 percentage points. Code, models, and data will be released upon publication.
Figures & tables
Figure 1: Illustration of MMGNet. Given a single-view RGB-D observation, the image backbone extracts dense image features, which are aligned with the scene points through pixel–point correspondence and injected into successive stages of the 3D backbone to form image-informed 3D features. Rotational graspness prediction then scores joint view–in-plane rotations at candidate grasp centers. Based on the selected rotations, grasp-shaded grouping aggregates local image-informed features within the corresponding gripper frames. Finally, the operation head predicts the remaining depth-wise grasp scores and gripper widths to produce the final 6-DoF grasps.
Figure 2: (a) Grasp representation in MMGNet, showing the grasp coordinate frame with the red point marking the grasp origin. (b) Grasp-shaded grouping, where the black cuboid denotes the grouping region and the red points denote the grouped scene points.
Model
Input
Seen
Similar
Novel
Mean AP
GPD ten Pas et al. [2017]
P
22.87/24.38
21.33/23.18
8.24/9.58
17.48/19.05
PointNetGPD Liang et al. [2019]
P
25.96/27.59
22.68/24.38
9.23/10.66
19.29/20.88
Fang et al. Fang et al. [2023a]
P
27.56/29.88
26.11/27.84
10.55/11.51
21.41/23.08
RGB Matters Gou et al. [2021]
P+I
27.98/32.08
27.23/30.40
12.25/13.08
22.49/25.19
Li et al. Li et al. [2021]
P
36.55/ –
28.36/ –
14.01/ –
26.31/ –
HGGD Chen et al. [2023a]
P+I
59.36/60.26
51.20/48.59
22.17/18.43
44.24/42.43
Table 1: Comparison with state-of-the-art methods on the GraspNet-1Billion dataset Fang et al. [2023a] . Each entry reports RealSense/Kinect results.
Graspness Model
Fusion
AP
Seen
Similar
Novel
Mean
View
None
67.12
54.81
24.31
48.75
View
Hierarchical
71.97
58.37
25.50
51.95
Rotational
None
71.61
62.96
30.30
54.95
Rotational
Direct RGB ‡
71.86
61.84
28.85
54.18
Rotational
Early
76.50
68.44
32.22
59.05
Table 2: Comparison of graspness models and image-to-3D fusion.
Grouping
K
Seen
Similar
Novel
Mean
Δ Mean
Cylinder
8
68.32
59.86
28.22
52.13
-4.74
16
71.46
62.91
30.19
54.85
-2.02
32
73.50
65.69
31.41
56.87
0.00
64
74.02
66.04
31.67
57.24
+0.38
Grasp-shaded
8
76.13
69.90
31.76
59.26
-1.08
16
77.21
70.36
32.51
60.03
-0.31
Table 3: Sensitivity to the number of grouped local samples K under hierarchical image-to-3D injection. Δ denotes the mean AP change relative to K=32 for the same grouping type.
Target
Metric
View
Rotational
Δ
View graspness
Top-1 (%) ↑
3.80
4.25
+0.45
Rotation residual
Spearman ↑
0.311
0.367
+0.056
Exact Top-1 (%) ↑
35.76
39.15
+3.39
Regret ↓
0.2765
0.2516
−0.0250
Table 4: Representation analysis of pre-grouping image-informed 3D features.
Figure 3: Cross-modal representation analysis on the test set. The top row reports CKA, while the middle and bottom rows report bidirectional linear-probe R2 for 3D → image and image → 3D prediction, respectively. Columns correspond to Early, Hierarchical, Late (Concat), Late (Add), and Late (Gate).
Model
Modality
AP
Seen
Similar
Novel
Mean
GSNet Wang et al. [2021a]
P
67.12
54.81
24.31
48.75
+ Injection
P + I
71.97
58.37
25.50
51.95 ( +3.20 )
Ma et al. Ma and Huang [2023]
P
64.02
59.26
26.18
49.82
+ Injection
P + I
71.07
61.02
27.36
53.15 ( +3.33 )
Table 5: Transfer of hierarchical image-to-3D injection across different grasp methods.
Method
Reference Mean AP
Gaussian Noise
Smoothing
Perlin Region Dropout
GSNet Wang et al. [2021a]
55.92
9.25 (16.54)
49.19 (87.96)
50.13 (89.65)
Ma et al. Ma and Huang [2023]
57.68
25.02 (43.37)
49.43 (85.71)
52.79 ( 91.53 )
AnyGrasp Fang et al. [2023b]
60.42
30.45 (50.40)
50.27 (83.20)
53.04 (87.79)
Point-only
64.27
15.53 (24.16)
56.14 (87.35)
54.16 (84.26)
Ours
67.04
39.28 ( 58.60 )
59.11 ( 88.17 )
61.26 (91.38)
Table 6: Absolute mean AP under the strongest point corruptions. AP retention (%) relative to the uncorrupted synthetic-geometry reference is shown in parentheses.
Variant
Clean AP ↑
RGB-corrupted AP ↑
Point-only
54.95 (+0.00)
54.95 (+0.00)
Early
58.96 (+4.01)
56.47 (+1.51)
Late (Concat)
56.52 (+1.56)
54.34 (−0.61)
Late (Add)
58.52 (+3.56)
56.55 (+1.60)
Late (Gate)
56.59 (+1.64)
53.06 (−1.89)
Hierarchical (Ours)
60.33 (+5.38)
57.28 (+2.32)
Table 7: Utility under clean and RGB-corrupted observations. Parentheses show AP differences over Point-only under the same observation condition.
(a) Model latency comparison Model Time (ms) GSNet Wang et al. [2021a] 33.82 AnyGrasp Fang et al. [2023b] 44.55 Ma et al. Ma and Huang [2023] 784.05 Ours 71.74
Single-view RGB-D grasp detection remains a common choice in 6-DoF robotic grasping systems, which typically requires a depth sensor. While RGB-only 6-DoF grasp methods has been studied recently, their inaccurate geometric representation is not directly suitable for physically reliable robotic manipulation, thereby hindering reliable grasp generation. To address these limitations, we propose MG-Grasp, a novel depth-free 6-DoF grasping framework that achieves high-quality object grasping. Leveraging two-view 3D foundation model with camera intrinsic/extrinsic, our method reconstructs metric-scale and multi-view consistent dense point clouds from sparse RGB images and generates stable 6-DoF grasp. Experiments on GraspNet-1Billion dataset and real world demonstrate that MG-Grasp achieves state-of-the-art (SOTA) grasp performance among RGB-based 6-DoF grasping methods.
Kangxu Wang, Siang Chen, Chenxing Jiang +3
The Department of Electronic Engineering, Tsinghua University, Beijing 100084, China. · The Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
Dexterous grasping in multi-object scene constitutes a fundamental challenge in robotic manipulation. Current mainstream grasping datasets predominantly focus on single-object scenarios and predefined grasp configurations, often neglecting environmental interference and the modeling of dexterous pre-grasp gesture, thereby limiting their generalizability in real-world applications. To address this, we propose DGS-Net, an end-to-end grasp prediction network capable of learning dense grasp configurations from single-view point clouds in multi-object scene. Furthermore, we propose a two-stage grasp data generation strategy that progresses from dense single-object grasp synthesis to dense scene-level grasp generation. Our dataset comprises 307 objects, 240 multi-object scenes, and over 350k validated grasps. By explicitly modeling grasp offsets and pre-grasp configurations, the dataset provides more robust and accurate supervision for dexterous grasp learning. Experimental results show that DGS-Net achieves grasp success rates of 88.63% in simulation and 78.98% on a real robotic platform, while exhibiting lower penetration with a mean penetration depth of 0.375 mm and penetration volume of 559.45 mm^3, outperforming existing methods and demonstrating strong effectiveness and generalization capability. Our dataset is available at https://github.com/4taotao8/DGS-Net.
Humans can grasp objects effortlessly, whereas multi-fingered robots are far from this level of generality. We argue that the most natural source of robot grasping data is from humans, who pick up thousands of objects every day. We present HUG, a flow-matching model that generates diverse human grasps for any user-specified object in a single RGB-D image captured from a stereo camera. Using smart glasses, we first collect 1M-HUGs, an egocentric dataset of human grasps spanning 1M frames (27.8 hrs) and 6,707 object instances across 41 buildings. Next, to model the distribution of natural human grasps, our novel flow-matching model fuses RGB and depth observations to output a grasp parameterized by wrist translation, wrist rotation, and MANO hand pose. Predicted grasps can be retargeted to various robot hands, enabling zero-shot grasping in everyday scenes. To standardize evaluation, we build a new simulated benchmark, HUG-Bench, of 90 unseen objects from five geometric categories and various sizes, with metric-scale 3D meshes. We evaluate HUG in the real world on the 30-object test set of HUG-Bench across multiple stereo cameras, robot embodiments, and household environments. HUG outperforms the state-of-the-art grasping baselines by +23% and +34% on our challenging object set. Code, data, benchmark, checkpoints, and an interactive demo are released on our website: https://grasping.io/
Kevin Yuanbo Wu, Tianxing Zhou, Isaac Tu +5
New York University · Tsinghua University · University of Michigan