HF-WMBeyond Successful Robot DemonstrationsLearning from Human Interactions and Modeling Failure Dynamics

HF-WM teaser: Stage 1 supervised fine-tuning learns an action-conditioned world model from human to robot, and Stage 2 GRPO models failure outcomes without paired video supervision

Learning from Human Interactions

Stabilized pointflow bridges human and robot interactions.

Modeling Failure Dynamics

GRPO learns from failure-inducing actions without paired videos.

Real-World Policy Evaluation

Predicted futures closely reflect real-world policy performance.

Abstract

Action-conditioned world models offer a promising foundation for generalist robotic intelligence by predicting the consequences of actions. However, existing robotic datasets provide limited coverage of the diverse interaction dynamics required for generalizable world modeling. Large-scale egocentric human videos offer complementary interaction experience, yet the embodiment gap between human hands and robotic manipulators hinders effective cross-embodiment learning. Meanwhile, the predominance of successful demonstrations leaves failure dynamics substantially underrepresented, limiting the ability of world models to anticipate unsuccessful executions. To address these limitations, we introduce HF-WM, an action-conditioned world model that combines Human interaction learning with Failure-aware post-training. To bridge the embodiment gap, we develop a dual-branch framework that couples video generation with auxiliary pointflow prediction, using stabilized pointflow as a unified motion representation across human and robot interactions while suppressing egocentric camera motion. To improve failure modeling, we further perform Group Relative Policy Optimization (GRPO) post-training on perturbed actions derived from successful demonstrations, guided by action alignment and physics plausibility rewards, enabling the model to learn plausible failure dynamics without paired ground-truth videos. Extensive experiments demonstrate that HF-WM achieves state-of-the-art performance in action-conditioned video generation and exhibits strong utility for policy evaluation in downstream robotic tasks.

02 · Downstream validation

A · Policy Evaluation

HF-WM is used as a real-world policy evaluator on six RoboArena policies. For each session it receives only the initial observation and the policy action sequence, then autoregressively rolls out the future interaction. Task success is scored from these generated videos, and the resulting policy rates track real-world deployment with Pearson r = 0.983.

Extra RoboArena rollouts

Overview

RoboArena downstream success-rate comparison across policies
Pearson r 0.983 policy-rate correlation
Spearman ρ 0.956 rank correlation
Kendall τ 0.929 pairwise order
SISRΔ 2.4 pp mean |rate error|

Case 1

Place the square on the plate.

Case 2

Put the green cube in the pink bowl.

B · Test-Time Scaling for Policy Inference

At test time, HF-WM generates candidate futures for sampled actions and Robometer scores them before execution. Selecting the higher-scoring action shortens the executed trajectory relative to the π0.5 baseline, as shown in the two LIBERO-90 examples below.

TTC routing overview: HF-WM generates candidate actions, Robometer evaluates them, and the selected action is executed; the right panel compares HF-WM TTS with the pi0.5 baseline
Task 1
Before: 143 steps · After: 70 steps
Task 2
Before: 373 steps · After: 240 steps

03 · Comparison with baselines

Success Case 1

GT
HF-WM
OSCAR
cosmos3
Cosmos-Predict2.5
Tesseract
Kinema4D
Ctrl-World

Failure Case 1

GT
HF-WM
OSCAR
Ctrl-World
cosmos3
Cosmos-Predict2.5
Tesseract
Kinema4D

04 · Component ablations

w/o human data

GT
with human data
w/o human data

05 · Failure-aware post-training

Counterfactual actions expose failure dynamics; GRPO keeps the rollout that remains physically plausible.

Case 1 · failure-inducing action

Before GRPO, the perturbed action breaks the physical outcome

GRPO process
selected rejected

06 · Stabilized pointflow

HF-WM: camera-compensated 3D point trajectories on the left, and the dual-branch multimodal attention architecture on the right
Stabilized point flow and multimodal attention.

Left: camera-compensated 3D pointflow tracks object and gripper motion. Right: multimodal attention fuses vision, language, skeleton, action, and point-flow tokens for unified human–robot modeling.

Background jitter 5.31 → 1.04 pixels / frame (−80%) How far still background points jump each frame, in image pixels (px). Lower means less camera shake in the tracks.
Before · raw current-cameraAfter · frame-0 camera compensation