How to Instruct Your Robot: Dense Language Annotations Power Robot Policy Learning

TL;DR

DeMiAn method enhances robot policy learning with dense language annotations, boosting RoboCasa success by 5 points.

cs.RO 🔴 Advanced 2026-05-17 9 views
Bosung Kim Ruiyi Wang David Acuna Jaehun Jung Alexander Trevithick Brandon Cui Yejin Choi Prithviraj Ammanabrolu
robotics language annotation policy learning computer vision AI

Key Findings

Methodology

DeMiAn employs a two-stage process to enhance robot policy learning. First, it uses a vision-language model (VLM) to re-label existing demonstrations across four aspects: physical motion, scene composition, arm pose, and reasoning. Then, a small instructor model maps task descriptions and initial scene snapshots to appropriate task annotations, running asynchronously to hide generation latency.

Key Results

  • DeMiAn increased RoboCasa success rate by 5 percentage points, nearing the per-task oracle by 3 points.
  • In MolmoSpaces, scene composition annotation improved Pick tasks by 13 points, while reasoning annotation boosted NextTo tasks by 8 points.
  • DeMiAn improved compute-performance frontier in both mid-training and post-training, even after accounting for annotation-generation FLOPs.

Significance

This research positions dense language annotation as a practical scaling lever for robot policy learning, reducing the need for new demonstrations. By re-annotating existing datasets, DeMiAn shows potential to enhance policy learning performance without additional demonstration data, especially in complex tasks and out-of-distribution scenarios.

Technical Contribution

DeMiAn's technical contribution lies in its multi-aspect annotation strategy, which contrasts with existing single-style annotation methods. Through an asynchronous instructor, DeMiAn dynamically selects the most suitable annotation without adding latency, enhancing the flexibility and efficiency of policy learning.

Novelty

DeMiAn is the first to introduce multi-aspect dense language annotations in robot policy learning, breaking the limitation of single-style annotations and providing richer task information.

Limitations

  • DeMiAn still falls short of per-task oracle performance in certain tasks, indicating room for optimization in annotation selection.
  • The performance of the asynchronous instructor depends on the quality of the initial scene snapshot, which may affect performance in complex scenarios.

Future Work

Future work could explore further optimization of annotation selection strategies and validate DeMiAn's effectiveness on larger and more diverse datasets.

AI Executive Summary

Scaling robot policy learning is often constrained by the high cost of demonstration data collection, while language annotations are relatively inexpensive. The DeMiAn method enhances policy learning efficiency through dense language annotations. Initially, DeMiAn uses a vision-language model to re-label existing demonstrations across four aspects: physical motion, scene composition, arm pose, and reasoning. Subsequently, a small instructor model maps task descriptions and initial scene snapshots to appropriate task annotations, running asynchronously to hide generation latency.

Across over 1 million robot manipulation clips and 50,000 EgoVerse videos, DeMiAn significantly improved policy learning performance. On the RoboCasa dataset, DeMiAn increased success rates by 5 percentage points, nearing the per-task oracle by 3 points. Additionally, DeMiAn improved the compute-performance frontier in both mid-training and post-training, even after accounting for annotation-generation FLOPs.

However, DeMiAn still falls short of per-task oracle performance in certain tasks, indicating room for optimization in annotation selection. Future work could explore further optimization of annotation selection strategies and validate DeMiAn's effectiveness on larger and more diverse datasets.

Deep Analysis

Background

Robot policy learning has seen significant advancements in recent years, yet it still faces the challenge of high data collection costs. Existing methods often rely on large amounts of demonstration data, which require thousands of skilled operator hours on dedicated hardware. Language annotation offers a new possibility as a low-cost signal amplification tool.

Core Problem

The core issue is how to improve policy learning efficiency without increasing demonstration data. Existing single-style annotation methods fail to fully exploit the implicit information in demonstration data, limiting policy learning performance.

Innovation

DeMiAn's core innovation lies in its multi-aspect dense language annotation strategy. By annotating demonstration data across physical motion, scene composition, arm pose, and reasoning, DeMiAn provides richer task information, breaking the limitation of single-style annotations.

Methodology

  • �� Use a vision-language model to re-label existing demonstrations across four aspects.
  • �� Train a small instructor model to map task descriptions and initial scene snapshots to appropriate task annotations.
  • �� The instructor runs asynchronously to hide generation latency.

Experiments

Experiments were conducted on over 1 million robot manipulation clips and 50,000 EgoVerse videos. Evaluations were performed using RoboCasa and MolmoSpaces datasets, comparing the impact of different annotation strategies on policy learning performance.

Results

DeMiAn increased RoboCasa success rate by 5 percentage points, nearing the per-task oracle by 3 points. In MolmoSpaces, scene composition annotation improved Pick tasks by 13 points, while reasoning annotation boosted NextTo tasks by 8 points.

Applications

DeMiAn can be directly applied to robotic manipulation tasks, especially in complex tasks and out-of-distribution scenarios. Its multi-aspect annotation strategy provides richer information for policy learning.

Limitations & Outlook

DeMiAn still falls short of per-task oracle performance in certain tasks, indicating room for optimization in annotation selection. The performance of the asynchronous instructor depends on the quality of the initial scene snapshot, which may affect performance in complex scenarios.

Plain Language Accessible to non-experts

Imagine you're cooking in a kitchen. You have an assistant who tells you what to do at each step, but he can only use simple words. DeMiAn is like a smarter assistant who not only tells you what to do but also explains why and how to do it better. It's like knowing not just to add salt, but why adding salt makes the food taste better.

ELI14 Explained like you're 14

Imagine you're playing a game where you need to complete various tasks, like opening a cabinet or picking up an item. DeMiAn is like a super assistant who not only tells you what to do but also explains why and how to do it better. It's like knowing not just which button to press, but why pressing that button will help you win the game!

Glossary

Vision-Language Model (VLM)

A model that combines visual and language information to generate or understand language descriptions.

Used to generate dense language annotations.

RoboCasa

A dataset used for evaluating robotic manipulation tasks, containing various kitchen tasks.

Used to evaluate DeMiAn's performance.

EgoVerse

A human-egocentric video dataset used for training and evaluating robot policies.

Used to validate DeMiAn's performance in complex scenarios.

Asynchronous Instructor

A model that asynchronously generates task annotations during policy execution.

Used to hide generation latency and improve policy learning efficiency.

Dense Language Annotation

Detailed language descriptions of demonstration data across multiple aspects to provide richer task information.

Used to enhance robot policy learning efficiency.

Open Questions Unanswered questions from this research

  • 1 How can annotation selection strategies be further optimized to reach per-task oracle performance?
  • 2 How effective is DeMiAn on larger and more diverse datasets?

Applications

Immediate Applications

Robotic Manipulation Tasks

DeMiAn can be used in complex robotic manipulation tasks, providing richer task information and improving policy learning efficiency.

Long-term Vision

Intelligent Assistant Systems

In the future, DeMiAn's multi-aspect annotation strategy could be used to develop more intelligent assistant systems, helping users complete tasks more efficiently.

Abstract

Scaling robot policy learning is bottlenecked by the cost of collecting demonstrations, while language annotations for existing demonstrations are comparatively cheap. We study language density as a lever for extracting more signal from a fixed robot or egocentric-video corpus. We introduce DeMiAn (Dense Multi-aspect Annotation), a two-stage approach that first re-labels demonstration segments with VLM-generated annotations along four complementary aspects: physical motion, scene composition, arm pose, and reasoning. A learned instructor then maps a task description and initial scene snapshot to a task-appropriate annotation at deployment, running asynchronously so generation latency is hidden behind policy execution. Across over 1M robot manipulation clips and 50K EgoVerse human-egocentric videos, DeMiAn improves both a vision-language-action policy and a video-based world-action model without collecting new demonstrations. On RoboCasa, the instructor raises success by 5 points over a task-only baseline and comes within 3 points of a per-task oracle. No fixed annotation aspect dominates across tasks, showing that selecting the right dense language matters. DeMiAn also improves composite-task and out-of-distribution performance, and shifts the compute-performance frontier in both mid-training and post-training after accounting for annotation-generation FLOPs. These results position dense re-annotation as a practical scaling lever for robot policy learning.

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