Hi Robot: Open-Ended Instruction Following with Hierarchical Vision-Language-Action Models

TL;DR

This paper introduces a hierarchical vision-language-action system for generalist robots capable of understanding complex instructions and feedback, enabling them to perform diverse tasks across different robotic platforms.

Contribution

The work presents a novel hierarchical model that integrates reasoning over complex prompts and feedback with low-level action execution for versatile robot task performance.

Findings

Successfully handled complex instructions and feedback in real-world tasks

Demonstrated across multiple robotic platforms including single-arm and dual-arm robots

Achieved effective task completion in scenarios like cleaning, cooking, and shopping

Abstract

Generalist robots that can perform a range of different tasks in open-world settings must be able to not only reason about the steps needed to accomplish their goals, but also process complex instructions, prompts, and even feedback during task execution. Intricate instructions (e.g., "Could you make me a vegetarian sandwich?" or "I don't like that one") require not just the ability to physically perform the individual steps, but the ability to situate complex commands and feedback in the physical world. In this work, we describe a system that uses vision-language models in a hierarchical structure, first reasoning over complex prompts and user feedback to deduce the most appropriate next step to fulfill the task, and then performing that step with low-level actions. In contrast to direct instruction following methods that can fulfill simple commands ("pick up the cup"), our system can reason through complex prompts and incorporate situated feedback during task execution ("that's not trash"). We evaluate our system across three robotic platforms, including single-arm, dual-arm, and dual-arm mobile robots, demonstrating its ability to handle tasks such as cleaning messy tables, making sandwiches, and grocery shopping. Videos are available at https://www.pi.website/research/hirobot