3DFlowAction: Learning Cross-Embodiment Manipulation from 3D Flow World
  Model
Authors: name: Hongyan Zhi, name: Peihao Chen, name: Siyuan Zhou, name: Yubo Dong, name: Quanxi Wu, name: Lei Han, name: Mingkui Tan

Manipulation has long been a challenging task for robots, while humans can
effortlessly perform complex interactions with objects, such as hanging a cup
on the mug rack. A key reason is the lack of a large and uniform dataset for
teaching robots manipulation skills. Current robot datasets often record robot
action in different action spaces within a simple scene. This hinders the robot
to learn a unified and robust action representation for different robots within
diverse scenes. Observing how humans understand a manipulation task, we find
that understanding how the objects should move in the 3D space is a critical
clue for guiding actions. This clue is embodiment-agnostic and suitable for
both humans and different robots. Motivated by this, we aim to learn a 3D flow
world model from both human and robot manipulation data. This model predicts
the future movement of the interacting objects in 3D space, guiding action
planning for manipulation. Specifically, we synthesize a large-scale 3D optical
flow dataset, named ManiFlow-110k, through a moving object auto-detect
pipeline. A video diffusion-based world model then learns manipulation physics
from these data, generating 3D optical flow trajectories conditioned on
language instructions. With the generated 3D object optical flow, we propose a
flow-guided rendering mechanism, which renders the predicted final state and
leverages GPT-4o to assess whether the predicted flow aligns with the task
description. This equips the robot with a closed-loop planning ability.
Finally, we consider the predicted 3D optical flow as constraints for an
optimization policy to determine a chunk of robot actions for manipulation.
Extensive experiments demonstrate strong generalization across diverse robotic
manipulation tasks and reliable cross-embodiment adaptation without
hardware-specific training.