Organizations: Hong Kong University of Science and Technology (Guangzhou) · Harbin Institute of Technology, Shenzhen · Shenzhen University · University of Cambridge
Equipping humanoid robots with versatile interaction skills typically requires either extensive policy training or explicit human-to-robot motion retargeting. However, learning-based policies face prohibitive data collection costs. Meanwhile, retargeting relies on human-centric pose estimation (e.g., SMPL), introducing a morphology gap. Skeletal scale mismatches result in severe spatial misalignments when mapped to robots, compromising interaction success. In this work, we propose Dream2Act, a robot-centric framework enabling zero-shot interaction through generative video synthesis. Given a third-person image of the robot and target object, our framework leverages video generation models to envision the robot completing the task with morphology-consistent motion. We employ a high-fidelity pose extraction system to recover physically feasible, robot-native joint trajectories from these synthesized dreams, subsequently executed via a general-purpose whole-body controller. Operating strictly within the robot-native coordinate space, Dream2Act avoids retargeting errors and eliminates task-specific policy training. We evaluate Dream2Act on the Unitree G1 across four whole-body mobile interaction tasks: ball kicking, sofa sitting, bag punching, and box hugging. Dream2Act achieves a 37.5% overall success rate, compared to 0% for conventional retargeting. While retargeting fails to establish correct physical contacts due to the morphology gap (with errors compounded during locomotion), Dream2Act maintains robot-consistent spatial alignment, enabling reliable contact formation and substantially higher task completion.
Figures & tables
Figure 1: Dream2Act: Zero-shot Humanoid Interaction via Robot-Centric Video Synthesis. (A) Traditional human-centric retargeting fails due to the morphology gap, causing spatial misalignments. (B) Our Dream2Act pipeline leverages Seedance 2.0 to synthesize morphology-consistent interactions directly in the robot’s native space. (C) This visual prior translates into successful zero-shot physical execution for spatially-sensitive tasks like sitting on a sofa and kicking a ball.
Figure 2: Dream2Act System Architecture. The framework comprises three core modules: (1) Interaction Hallucination via Seedance to generate morphology-consistent visual priors; (2) Native Pose Estimation and 2D-to-3D Lifting to extract precise 3D keypoints; and (3) Morphology-Aware Kinematic Recovery employing Constrained IK and PnP scale recovery to trajectories for physical execution.
Figure 3: G1 Domain-Specific Hybrid Dataset Construction Pipeline. Our approach synergizes cost-free, high-fidelity 3D/2D geometry rendered from a 9-camera simulation environment (Isaac Lab) with Human-in-the-Loop (HITL) annotations to correct visual domain shifts, enabling robust native pose estimation.
Figure 4: Qualitative Comparison on Diverse Spatially-Sensitive Tasks. We evaluate zero-shot performance across Kicking, Hugging, Punching, and Sitting. (Top) Traditional human-centric retargeting suffers from spatial misalignments and kinematic violations due to the morphology gap. (Bottom) Dream2Act’s robot-centric hallucination ensures precise contacts and dynamic stability.
Method
Ball-kicking ( 1.64m Avg )
Box-hugging ( 0.75m )
Bag-hitting ( 1.60m )
Sofa-sitting ( 1.10m )
Succ ↑
Err ↓ (m)
Succ ↑
Err ↓ (m)
Succ ↑
Err ↓ (m)
Succ ↑
Err ↓ (m)
Baseline
0%
0.75
0%
0.35
0%
0.70
0%
0.65
Dream2Act (Ours)
40%
0.14
10%
0.11
30%
0.10
70%
0.28
Table 1: Quantitative comparison on four zero-shot interaction tasks. Task Length (in italics) denotes the initial distance to the target. Dream2Act significantly outperforms human-centric baselines, effectively bounding spatial alignment errors.
Figure 5: Spatial Generalization Analysis on Multi-Location Ball Kicking. To verify scale adaptability, we evaluate Dream2Act across four distinct ball positions. (Top) Human-centric retargeting fails to replicate spatial variations due to the morphology gap. (Bottom) Dream2Act successfully hallucinates and executes kicks for all targets, demonstrating robust spatial diversity.
Method
Kick Ball (a) ( 0.90m )
Kick Ball (b) ( 2.05m )
Kick Ball (c) ( 1.45m )
Kick Ball (d) ( 2.18m )
Succ ↑
Err ↓ (m)
Succ ↑
Err ↓ (m)
Succ ↑
Err ↓ (m)
Succ ↑
Err ↓ (m)
Baseline
0%
0.53
0%
0.82
0%
0.84
0%
0.79
Dream2Act (Ours)
60%
0.19
20%
0.09
60%
0.09
20%
0.19
Table 2: Quantitative comparison on multi-location ball-kicking. Task lengths vary from 0.90m to 2.18m. Dream2Act maintains precise spatial alignment across all targets, avoiding the error accumulation seen in baselines.
Figure 6: Qualitative Comparison of Text-to-Motion Pipelines in Free Space. Human-centric T2M models amplify inherent artifacts during retargeting, causing dynamic constraint violations and hardware failure. Dream2Act strictly enforces physical consistency, achieving stable zero-shot deployment.
Figure 7: Qualitative Ablation on Native G1 Pose Estimation. Given a challenging real-world image: (a) Zero-shot ViTPose (COCO-only) completely misidentifies robot features; (b) A Sim-Only variant suffers from local drift due to domain shift; (c) Our Dream2Act native estimator, fine-tuned on the hybrid dataset, achieves pixel-perfect alignment.
Table 3: 2D Pose Estimation Performance on 12 Common Joints. We compare zero-shot generalization of standard human estimators (COCO-17) vs. our domain-specific model on shared kinematic joints.
Robot motion generation creates feasible, task-directed trajectories for robots to move, manipulate objects, and interact with people and environments.
Humanoid robots have the potential to perform dexterous manipulation in human environments, yet acquiring diverse and generalizable skills remains costly due to expensive hardware data collection and labor-intensive annotation. Recent advances in video generative models provide a promising opportunity to synthesize rich manipulation experiences from visual observations, but transferring such imagined behaviors into executable whole-body humanoid skills remains largely unexplored. In this work, we present RoboReact, a framework that automatically synthesizes whole-body humanoid manipulation skills from a single egocentric RGB-D observation. RoboReact generates human manipulation videos, extracts geometry-preserving interaction keyframes through depth-aware 3D reconstruction, and retargets them to high-DoF humanoid platforms while preserving hand-object interaction geometry. To bridge the gap between imagined plans and physical execution, RoboReact performs online object-centric re-grounding and leverages a vision-language model-guided refinement loop to adapt skills under geometric mismatch and execution deviations. The refined skills are executed through a whole-body controller, enabling coordinated whole-body manipulation and dexterous interaction. Experiments on real humanoid robots demonstrate that RoboReact generalizes across diverse object configurations and robustly recovers from execution disturbances without requiring teleoperation or human demonstrations. These results highlight the potential of combining generative models, vision-language reasoning, and closed-loop control for scalable humanoid skill acquisition.
Shuliang He, Shuai Wang, Bo Yue +3
The Chinese University of Hong Kong, Shenzhen · JD Technology · Tsinghua University
Whole-body Humanoid-Object Interaction (HOI) is bottlenecked by the scarcity of high-fidelity 3D data. While video generative priors offer a promising alternative, existing methods suffer from Representation Misalignment due to their reliance on geometric priors (e.g., explicit CAD models), and Retargeting Complexity arising from intensive morphing and morphological mismatch. We propose Imagine2Real, a zero-shot HOI framework for flexible, geometry-free interaction. To resolve misalignment, we formulate robot and object motions as unified 4D point trajectories. To overcome retargeting complexity, our Keypoints Tracker tracks only sparse critical points (base, hands, and object), entirely bypassing the error-amplifying retargeting process. To maintain natural gaits despite these sparse signals, we utilize the latent space of a Behavior Foundation Model (BFM) as the tracker's search domain. Using a progressive training strategy, Imagine2Real learns robust behaviors with simple tracking rewards, enabling zero-shot physical deployment within a motion capture(mocap) system.
Jiahe Chen, ZiRui Wang, Feiyu Jia +7
Zhejiang University · Shanghai AI Laboratory · The Chinese University of Hong Kong
Retargeting human motion to humanoid robots is critical for teleoperation, imitation learning and human-robot interaction. However, it remains challenging because of substantial morphological discrepancies between humans and robots, including differences in skeletal topology, limb proportions and degrees of freedom, as well as the scarcity of paired motion data. This paper presents Human2Humanoid, an unsupervised motion retargeting framework that transfers human motions to humanoid robot behaviors with high fidelity. To bridge the domain gap under unpaired data, we adopt a CycleGAN-based architecture equipped with a skeleton-aware graph convolutional network to capture topology-dependent motion features. To address cross-domain scale mismatches, we introduce a morphology-invariant end-effector consistency loss that aligns normalized end-effector trajectories to preserve motion semantics across embodiments. To improve physical plausibility and reduce contact artifacts, we impose explicit physics-aware feasibility constraints to encourage reproduction of the contact patterns in the source motion. Experimental results show that the proposed method successfully retargets human motion to the Unitree G1 humanoid robot without paired data, and outperforms existing methods in both downstream controllability and physical feasibility.
Tianchen Huang, Feiyang Yuan, Junchi Gu +5
Institute of Humanoid Robots, Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui 230026, China