Developing robust autonomous loco-manipulation skills for humanoids remains an open problem in robotics. While RL has been applied successfully to legged locomotion, applying it to complex, interaction-rich manipulation tasks is harder given long-horizon planning challenges for manipulation. A recent approach along these lines is DreamControl, which addresses these issues by leveraging off-the-shelf human motion diffusion models as a generative prior to guide RL policies during training. In this paper, we investigate the impact of DreamControl's motion prior and propose an improved framework that trains a guided diffusion model directly in the humanoid robot's motion space, aggregating diverse human and robot datasets into a unified embodiment space. We demonstrate that our approach captures a wider range of skills due to the larger training data mixture and establishes a more automated pipeline by removing the need for manual filtering interventions. Furthermore, we show that scaling the generation of reference trajectories is important for achieving robust downstream RL policies. We validate our approach through extensive experiments in simulation and on a real Unitree-G1.
Figures & tables
Figure 2: DreamControl-v2 Overview. Our four-stage pipeline enables humanoid whole-body manipulation: (1) large-scale human motion datasets are retargeted into a unified robot-space; (2) a humanoid motion diffusion model is trained to generate reference trajectories conditioned on text and spatio-temporal control signal; (3) multiple reference trajectories are used to train a physics-based RL policy; (4) The learned policy is deployed in simulation and on a real robot.
Train Data
# Samples (K)
FID ↓
R-Precision ↑
Diversity →
Control L2 ↓
Skating Ratio ↓
Downstream RL Policy ↑
Top-1
Top-2
Top-3
(3.362)
Group-1
Group-2
Zero-Shot
-
0.981
0.105
0.260
0.329
3.647
0.112
0.101
0.040
0.995
AMASS
21.8
0.305
0.110
0.184
0.266
3.174
0.104
0.142
0.030
0.985
AMASS + Nymeria
26.4
0.298
0.101
0.204
0.281
3.084
0.108
0.132
0.860
0.985
Full-Mix
29.6
0.265
0.114
0.217
0.388
3.252
0.066
0.096
0.925
0.985
Table I : Comparison Across Training Data Mixtures. We evaluate diffusion models trained on three data configurations: AMASS, AMASS + Nymeria, and Full-Mix. For downstream control, we additionally report the average RL policy success ratio (in simulation). Refer to Sec. IV-A for details related to baselines, and note that zero-shot refers to fully automated DreamControl [ 7 ] for RL evaluation, and diffusion is evaluated using OmniControl [ 7 ] . All results are evaluated on the Full-Mix test set.
Train Data
FID ↓
R-Precision ↑
Control L2 ↓
Skating Ratio ↓
AMASS Test Set
AMASS
0.328
0.291
0.070
0.100
Full-Mix
0.320
0.280
0.050
0.120
Non-AMASS Test Set
AMASS
2.720
0.117
0.065
0.539
Full-Mix
0.316
0.264
0.042
0.032
Table II : Comparison Across Test Splits. We report FID, R-Precision (Top-3), Control L2, and Skating Ratio on two distinct evaluation sets: (1) the AMASS Test Set , and (2) a Non-AMASS Test Set constructed from Nymeria (subset), GRAB, and OmniRetarget samples within the Full-Mix distribution.
Figure 3: Effect of Trajectory Scaling on RL Performance. More diffusion-generated trajectories consistently lead to higher policy success ratios across 3 different tasks. The figure on the right indicates the variance of test distribution on multiple tasks.
Task
Success Ratio ↑
Control Error ↓
Pick
0.99
0.03
Punch
0.99
0.04
Deep Squat & Pick
0.94
0.06
Drawer Open
0.96
0.02
Pour
0.92
0.03
Vertical Wipe
1.00
0.04
Table III : Task-wise Performance . We report the Success Ratio and Control Error (m) averaged over 100 randomized simulation environments for all 8 tasks in our skill library.
Figure 4: Spatial Prompting Qualitative Results. The figure depicts successful ( ) and rejected samples ( ) obtained from various spatial prompting techniques. The DreamControl-v2 model is directly prompted in robot space (blue line), trial-and-error is used for the zero-shot model (red line), and prompt calibration is indicated with green lines.
Method
FID ↓
Ctrl L2 ↓
Valid Traj.(%)
Prompt-Calib. ( AMASS )
2.010
0.180
8.0
Prompt-Calib. ( Full-Mix )
3.260
0.260
4.0
Pre-retargetting ( Full-Mix )
0.265
0.066
68.0
Table IV : Prompt calibration vs. pre-retargeting. Prompt-Calib. uses samples from the zero-shot OmniControl model [ 7 ] . FID and Ctrl L2 are evaluated on the respective AMASS and Full-Mix test sets. Valid Traj. (%) is reported for the Pick task corresponding to AMASS and the Drawer Open task for Full-Mix. Our Pre-retargeting method is evaluated on Full-Mix and Valid Traj.(%) represents the average across both tasks.
Pretrained
Iters ×103
FID ↓
R@3 ↑
Ctrl L2 ↓
Skt Ratio ↓
✗
104
0.741
0.254
0.114
0.112
✓
102
0.265
0.388
0.066
0.096
Table V : Network Initialization . We report FID, R-Precision (Top-3), Control L2 and Skating Ratio for models randomly initialized ( ✗ ) and with the pretrained weights from MDM [ 17 ] ( ✓ ).
SMPL
G1 link name
pelvis
pelvis_contour_link
left hip
left_hip_pitch_link
right hip
right_hip_pitch_link
left knee
left_knee_link
right knee
right_knee_link
left ankle
left_ankle_roll_link
Table VI : Human and G1 link correspondances for retargetting
Human
G1 link name
pelvis
pelvis contour link
left hip
left hip pitch link
right hip
right hip pitch link
spine 1
imu link
left knee
left knee link
right knee
right knee link
Table VII : SMPL and G1 link keypoint correspondances for Trajectory represenatation
Figure 4: Key-point correspondences used for retargetting human data to G1. A similar correspondence mapping is used for diffusion trajectory representation Sec. III-B1 .
Imitating human demonstrations has emerged as a dominant paradigm for learning humanoid loco-manipulation policies. However, scaling these approaches remains challenging due to the high cost of collecting diverse demonstrations and the need for continual human intervention to correct policy failures. In this paper, we present a self-supervised framework that bootstraps from sparse demonstrations and progressively expands its behavioral repertoire, enabling the learning of a goal-conditioned policy that automatically explores the goal space with minimal expert supervision. Our approach combines diffusion-based trajectory generation with reinforcement learning, where the latter is used to track goal-conditioned trajectories produced by the diffusion model for a range of loco-manipulation skills. Through extensive ablation studies and comparisons with state-of-the-art methods, we demonstrate the effectiveness of our framework on multiple humanoid loco-manipulation skills.
Pranav Debbad, Kanish Thiagarajan, Victor Dhédin +2
Munich Institute of Robotics and Machine Intelligence (MIRMI), Technical University of Munich (TUM), Germany.
Vision-based whole-body loco-manipulation on humanoid robots is challenging due to partial observability, contact-rich dynamics, and the difficulty of learning long-horizon behaviors from high-dimensional visual inputs. We present DreamMimic, a framework that distills privileged teacher policies into vision-based humanoid controllers via world-model-assisted distillation. Instead of using a Dreamer-style RSSM for planning, we repurpose it to learn predictive latent dynamics that serve as both a representation space and an action-conditioned multi-step supervision signal, while exposing compact predictive features to the student policy to reduce long-term drift. Beyond standard reconstruction objectives for proprioceptive and visual observations, we add auxiliary prediction heads for privileged state, contact, object state, and reward estimation. These heads provide additional supervision related to agent--object interaction and task progress, encouraging the latent representation to retain signals that are useful for contact-rich loco-manipulation. We further introduce Performance-Conditioned Guidance (PCG), a reward-driven adaptive distillation schedule that computes performance scores for both teacher and student to dynamically balance guidance and exploration. PCG prevents both premature teacher annealing and excessive teacher interference in challenging visual settings. Experiments on OMOMO and BEHAVE show improved tracking-based loco-manipulation performance over strong vision-based baselines, without exposing online privileged interaction states to the student at deployment. Qualitative simulations further examine morphology and simulator changes. These results suggest that world models can provide a useful mechanism for stabilizing visual policy distillation in contact-rich humanoid behaviors.
Humanoid loco-manipulation requires coordinated task-space motion planning with stable loco-manipulation command tracking under complex robot-environment dynamics and long-horizon tasks. While diffusion policies (DPs) show promise for learning from demonstrations, deploying them on humanoids poses critical challenges: the motion planner trained offline is decoupled from the loco-manipulation controller, leading to poor command tracking, compounding distribution shift, and task failures. The common approach of scaling demonstration data is prohibitively expensive for high-dimensional humanoid systems. To address this challenge, we present REFINE-DP (REinforcement learning FINE-tuning of Diffusion Policy), a hierarchical framework that jointly optimizes a DP motion planner and an RL-based loco-manipulation controller. The DP is fine-tuned via a PPO-based diffusion policy gradient to improve task success rate, while the controller is simultaneously updated to accurately track the planner's evolving command distribution, reducing the distributional mismatch that degrades motion quality. We validate REFINE-DP on a humanoid robot performing loco-manipulation tasks, including door traversal and long-horizon object transport. REFINE-DP achieves an over 90% success rate in simulation, even in out-of-distribution cases not seen in the pre-training data, and enables real-world execution without privileged state information. Our proposed method substantially outperforms pre-trained DP baselines and demonstrates that RL fine-tuning is key to reliable humanoid loco-manipulation. https://refine-dp.github.io/REFINE-DP/
Zhaoyuan Gu, Yipu Chen, Zimeng Chai +11
Institute for Robotics and Intelligent Machines, Georgia Institute of Technology, Atlanta, GA 30332 USA