Skeleton-Grounded Latent Action Model for Robot World Models
TLDR
SkeLAM decomposes latent actions into skeleton-guided kinematic and residual components, enabling controllable robot world models that generate future observations from actions.
Reasoning
The paper introduces a novel skeleton-guided latent action decomposition with cross-modal swap reconstruction and adapter-based action conditioning, supported by strong DROID benchmark results and zero-shot transfer. Weaknesses include limited discussion of limitations and the abstract truncating policy evaluation details.
Read-first score
Read-first score 38.3, weighted from topical fit, citation, graph, method, reproducibility, and recency signals. Original total remains 53.
Field roles
Rank sensitivity
Stability: volatile; rank range: 498.
Keyword Scores
Deep Analysis
Innovations
- Decomposes latent actions into a skeleton-grounded kinematic component and a residual component to separate robot motion from complementary visual dynamics.
- Uses cross-modal swap reconstruction to encourage RGB-derived and skeleton-derived kinematic representations to be interchangeable during video reconstruction.
- Introduces separate conditioning pathways and branch dropout to reduce dependence on future-derived residual information.
- Maps robot actions to kinematic space via a lightweight adapter, followed by world-model fine-tuning for controllable generation.
Methodology
SkeLAM learns robot world models from videos on DROID by decomposing latent actions into skeleton-supervised kinematic and residual components. It uses cross-modal swap reconstruction, separate conditioning pathways, and branch dropout, then maps robot actions to kinematic space with a lightweight adapter and fine-tunes the world model. Evaluation compares against DreamDojo using end-effector ADE and LPIPS, with motion probing, qualitative transfer, and real-robot policy success agreement.
Key Results
On DROID, SkeLAM reduces end-effector ADE by 19.5% and LPIPS by 11.1% compared with DreamDojo. Motion probing supports kinematic specialization, qualitative results demonstrate zero-shot human-to-robot motion transfer, and policy evaluation shows agreement between predicted and real-robot success rates.