CLASP: Closed-loop Asynchronous Spatial Perception for Open-vocabulary Desktop Object Grasping
Authors: Yiran Ling, Wenxuan Li, Siying Dong, Yize Zhang, Xiaoyao Huang, Jing Jiang, Ruonan Li, Jie Liu
Organizations: Harbin Institute of Technology · National Key Laboratory of Smart Farm Technologies and Systems · Northeastern University · Peng Cheng Laboratory
Robot grasping of desktop object is widely used in intelligent manufacturing, logistics, and agriculture.Although vision-language models (VLMs) show strong potential for robotic manipulation, their deployment in low-level grasping faces key challenges: scarce high-quality multimodal demonstrations, spatial hallucination caused by weak geometric grounding, and the fragility of open-loop execution in dynamic environments. To address these challenges, we propose Closed-Loop Asynchronous Spatial Perception(CLASP), a novel asynchronous closed-loop framework that integrates multimodal perception, logical reasoning, and state-reflective feedback. First, we design a Dual-Pathway Hierarchical Perception module that decouples high-level semantic intent from geometric grounding. The design guides the output of the inference model and the definite action tuples, reducing spatial illusions. Second, an Asynchronous Closed-Loop Evaluator is implemented to compare pre- and post-execution states, providing text-based diagnostic feedback to establish a robust error-correction loop and improving the vulnerability of traditional open-loop execution in dynamic environments. Finally, we design a scalable multi-modal data engine that automatically synthesizes high-quality spatial annotations and reasoning templates from real and synthetic scenes without human teleoperation. Extensive experiments demonstrate that our approach significantly outperforms existing baselines, achieving an 87.0% overall success rate. Notably, the proposed framework exhibits remarkable generalization across diverse objects, bridging the sim-to-real gap and providing exceptional robustness in geometrically challenging categories and cluttered scenarios.
Figures & tables
Fig. 1: Overview of the functional components of the CLASP framework: The figure shows the core modules, from natural language instruction input and dual-path awareness to VLM-based heuristic reasoning and closed-loop feedback mechanism.
Field
Value
Env.
Maniskill
Robot
widowx
Sim Freq
500
Control Freq
5
Static Friction
0.5
Dynamic Friction
0.5
TABLE I: Simulation Environments and Evaluation Settings
Fig. 2: Pick success rates of different attempts.
Config
Toys
Blocks
Tools
Total
banana
duck
lego
pear
teddy
cuboid
cylinder
semi-cylinder
ball
triangular
hammer
scissors
screwdriver
spatula
pliers
R
10.0%
100.0%
100.0%
40.0%
100.0%
20.0%
90.0%
90.0%
100.0%
100.0%
10.0%
20.0%
50.0%
0.0%
60.0%
59.3%
R+J
10.0%
100.0%
100.0%
40.0%
80.0%
30.0%
80.0%
90.0%
100.0%
100.0%
40.0%
30.0%
60.0%
0.0%
60.0%
61.3%
P+R+J
20.0%
100.0%
100.0%
40.0%
90.0%
80.0%
100.0%
100.0%
100.0%
100.0%
10.0%
0.0%
20.0%
20.0%
80.0%
64.0%
P+R+H+J
60.0%
100.0%
100.0%
80.0%
90.0%
100.0%
100.0%
100.0%
100.0%
100.0%
20.0%
50.0%
70.0%
30.0%
100.0%
80.0%
TABLE II: Component Effectiveness in Pick Tasks
Method
Toys
Blocks
Tools
Overall
Qwen3-VL [ 30 ]
92.00%
78.40%
46.40%
72.27%
Doubao-Seed [ 31 ]
88.00%
66.00%
52.00%
68.67%
AffordanceNet [ 32 ]
100.00%
72.00%
54.00%
75.33%
AnyGrasp [ 2 ]
63.20%
62.40%
44.00%
56.53%
CLASP(w/o pretrain)
86.00%
100.00%
54.00%
80.00%
CLASP(Ours)
100.00%
84.00%
77.00%
87.00%
TABLE III: Method Performance Comparison in General Pick Tasks
Policy
Exec. Time (s)
Avg. Time (s)
Var. (s 2 )
Streaming Policy
1613.3
107.6
1353.3
Asynchronous Policy
970.9
64.7
547.8
TABLE IV: Latency Benchmark: Streaming vs. Asynchronous Execution
Method
Toys
Tools
Blocks
Total
Qwen3-VL [ 30 ]
75.00%
50.00%
60.00%
63.33%
Doubao-Seed [ 31 ]
48.33%
58.33%
30.00%
46.67%
CLASP(Ours)
85.00%
70.00%
86.67%
83.33%
TABLE V: Performance comparison on different object categories
Fig. 3: The WidowX 250S 6-DoF robotic manipulator used in real-world experiments. (A) shows the performance of WidowX 250S 6-DoF robotic manipulator categorize mixed objects, selecting and placing tools(B), toys(C), and blocks(D) in a real environment
Fig. 4: Our CLASP method demonstrates superior effectiveness in physical settings, particularly in the precision and suitability of grasp point selection. While baseline methods show clear deficiencies—such as (B)Qwen3-VL selecting an incorrect grasp point, (C)segmentation-based methods failing to produce an available result, and (D)spatial-based methods identifying unsuitable, non-graspable positions on the edge—our method accurately determines the optimal opposing grasp locations on the wrench handle.