Motion for action · World Action Models

Trace-WAMLearning to Act via
3D Motion Prediction

for World Action Models

† Corresponding authors

Learning how the robot and objects move.
Turning future 3D motion into better actions.

98.7%LIBERO
84.5%LIBERO-Plus
80.3%RoboCasa-GR1 · Full data
85.0%Real world · Average
01 / The idea

The future is more
than appearance.
It is motion.

World Action Models couple future visual prediction with action generation. But successful manipulation depends on how the robot and task-relevant objects move—not just how the next frame looks.

Trace-WAM adds future 3D motion prediction as an auxiliary objective. Tracking the same points through time captures both image-plane displacement and depth change, providing a direct learning signal for interaction dynamics.

Learn with future motion.
Act from current observations.

02 / The method

Three experts.
One efficient policy.

Joint training enriches the representations used for action generation.

Trace-WAM architecture: video, motion, and action experts in a Mixture-of-Transformer, with training and inference attention masks. Future video and 3D motion prediction provide training-only supervision.

Tri-MoT architecture. Three Transformer experts jointly learn video prediction, 3D motion prediction, and action generation. At inference, action denoising uses cached visual features; future-video and motion prediction are removed.

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01

Same points, through time

Persistent point correspondence ties the robot and objects to their future trajectories.

02

Beyond the image plane

Image displacement and depth change describe motion in a unified reference-camera frame.

03

Auxiliary at training time

Deployment uses a single visual forward pass and action denoising, without future motion generation.

03 / Real-world manipulation

Motion learned.
Actions grounded.

Three tasks on a Piper robot, from precise placement to sustained interaction.

85.0%average success rate
Real world

Place Bread

85%

Place the bread in the bowl.

Real world

Place and Close Drawer

95%

Place the object inside, then close the drawer.

Real world

Wipe Blackboard

75%

Erase the chalk markings from the board.

Representative successful executions · 20 evaluation trials per task and method

+21.7 percentage points in average success over Fast-WAM. Explore the complete results ↓

04 / Simulation

Across tasks.
Across environments.

From diverse manipulation tasks to seven dimensions of distribution shift.

Representative successful rollouts · Click a video to play
05 / Benchmarks

Stronger action learning.

Success rates across three simulation benchmarks.

06 / The paper

Learning motion.
Improving action.

Explore the full method, experimental results, and the details behind motion-auxiliary learning.

Read the paper
THE PAPER Figure 1: simulation and real-world motion annotations, Trace-WAM auxiliary learning, benchmark performance, and real-world executions. Trace-WAM

Learning to Act via 3D Motion Prediction for World Action Models