Agentic robot learning

ARSTAG

An Agentic Real2Sim2Real System
for Task-Specific Robot Data Generation

Bowei LiYuner ZhangChangliu Liu

One image. One instruction.
Simulation demonstrations for real-world robot learning.

Learned policies on the real robot

Cone grasping2.07×
Brick grasping2.07×
Teapot handle1.19×
Screw shaft2.07×
Nut to plate3.12×
Bowl stacking3.12×

Selected real-robot executions. Playback speeds are shown for each clip.

The idea

Make the data, then learn the task.

Simulation can supply robot training data at scale. Preparing the scene, designing expert behavior, and configuring collection still require substantial work for each new task.

ARSTAG brings these stages into a coordinated agent workflow. Given a single RGB image and a natural-language instruction, specialized agents reconstruct the relevant scene, generate robot-feasible demonstrations, and train a visuomotor policy for real-world deployment.

7
real-world manipulation tasks
3
visuomotor policy architectures
1,000
simulation demonstrations per task
74.6%
Average real-world success across seven tasks with π0.5

Method

A coordinated path from image to policy.

A coordinator delegates work and uses tool feedback to guide revisions across stages.

ARSTAG architecture: an input image and instruction feed reconstruction, collection, and learning agents, coordinated through delegation, feedback, and recovery, before real-world evaluation.
ARSTAG reconstructs a task-scoped scene, generates demonstrations, and learns policies for real-robot execution. Click the figure to enlarge.
01 / Reconstruction

Reconstruct what the task needs.

Vision-language reasoning selects objects and their supports in a scene graph. Caption-guided segmentation and identity binding link graph objects to image masks. Object reconstruction and support repair produce a usable simulation scene.

02 / Collection

A training-free simulation expert.

The collection agent generates an expert that uses ground-truth simulation states and state-based skills. Feasibility screening and task-consistent randomization produce demonstrations, including recovery from disturbed states.

03 / Learning

Learn from simulated demonstrations.

The learning agent configures policy training and closed-loop simulation evaluation. The resulting visuomotor policies use visual observations and proprioception for real-robot execution.

Demonstration library

Across scenes, objects, and disturbances.

Browse more simulation and real-robot recordings, with paired comparisons of the reconstruction and data-generation stages.

Sampled scene 1

Screw-to-basket placement · 1× playback

Sampled scene 2

Screw-to-basket placement · 1× playback

Sampled scene 3

Screw-to-basket placement · 1× playback

Sampled scene 4

Screw-to-basket placement · 1× playback

Sampled scene 5

Screw-to-basket placement · 1× playback

Sampled scene 6

Screw-to-basket placement · 1× playback

Cone grasping

2.28× playback · operator-induced perturbation

Brick grasping

4.53× playback · operator-induced perturbation

Screw grasping

2.28× playback · operator-induced perturbation

Screw-to-basket placement

4.53× playback · operator-induced perturbation

Trajectory perturbation

The arm is displaced by 14 cm. The expert continues from the disturbed state. 2.1× playback.

Mis-grasp and target displacement

After an empty grasp, the object is relocated by 38 cm. The expert re-grasps it. 3.3× playback.

Bowl and supporting table: comparison of class-name matching and identity binding, with the corresponding instruction and mask assignments.
Bowl and supporting table Click to enlarge ↗
Repeated blocks and a plate: comparison of class-name matching and identity binding, with the corresponding instruction and mask assignments.
Repeated blocks and a plate Click to enlarge ↗
Mug with background distractors: comparison of class-name matching and identity binding, with the corresponding instruction and mask assignments.
Mug with background distractors Click to enlarge ↗
Teapot and supporting table: comparison of class-name matching and identity binding, with the corresponding instruction and mask assignments.
Teapot and supporting table Click to enlarge ↗

Purple blocks

Left: without repair · Right: with repair · 0.44× slow motion

Bottle

Left: without repair · Right: with repair · 0.44× slow motion

Blocks and plate

Left: without repair · Right: with repair · 0.09× slow motion

Pear and basket

Left: without repair · Right: with repair · 0.09× slow motion

Two cones

Left: without repair · Right: with repair · 0.09× slow motion

Screw and basket

Left: without repair · Right: with repair · 0.30× slow motion

Real-world evaluation

Simulation data. Real-robot execution.

Seven tasks cover general grasping, key-region grasping, placement, and stacking. All three policy architectures use the same generated demonstrations for each task.

Seven manipulation tasks grouped into general grasping, key-region grasping, pick-and-place, and stacking. Each column shows the task instruction, real input photograph, reconstructed simulation, and real-robot execution.
Seven tasks, from task instruction and real photograph to simulation and real-robot execution. View full resolution ↗
Real-robot closed-loop success rate (%)
TaskACTDiffusion Policyπ0.5
Cone grasping55.077.565.0
Brick grasping25.057.592.5
Teapot grasping40.067.572.5
Screw grasping62.572.590.0
Screw to basket42.562.560.0
Nut to plate35.062.567.5
Bowl stacking45.067.575.0
Average across seven tasks43.666.874.6

40 real-robot trials per task and policy. Bold values mark the highest success rate in each row.

Randomization ablation

Robustness beyond the collection conditions.

Leave-one-out ablations evaluate screw grasping under out-of-distribution conditions. Each cell reports success over 40 held-out simulation episodes.

OOD success rates with and without each randomization family
Tested familyFull recipeWithout family
Execution75.0%40.0%
Geometry62.5%40.0%
Background70.0%0.0%

Demonstration scale

More generated data improves policy success.

With 100,000 training steps held fixed, Diffusion Policy improves as the screw-grasping dataset grows. Each policy is evaluated over 40 held-out simulation episodes.

Success by number of generated demonstrations
DemonstrationsSuccess
500.0%
1007.5%
20027.5%
50052.5%
1,00062.5%

Execution randomization

Forced mis-grasp followed by target relocation. Same initial layout.

Geometry randomization

An out-of-distribution table and torso configuration. Same initial layout.

Background randomization

An unseen HDRI environment. Same initial layout and background.

The background video is a qualitative comparison: the full model uses a 200,000-step checkpoint and the ablated model a 100,000-step checkpoint. It does not isolate randomization under a matched training budget.

Agent execution profile

Agent activity, elapsed time, and token use through the workflow. The animation includes accelerated time and labeled milestones.

Fixed pipeline versus agent

The same task, tools, and collection/training budget. Tool feedback prompts the agent to revise the scene when the fixed pipeline stalls.