MoDem-V2: Visuo-Motor World Models for Real-World Robot Manipulation
Patrick Lancaster Nicklas Hansen Aravind Rajeswaran Vikash Kumar
Robotic systems that aspire to operate in uninstrumented real-world
environments must perceive the world directly via onboard sensing. Vision-based
learning systems aim to eliminate the need for environment instrumentation by
building an implicit understanding of the world based on raw pixels, but
navigating the contact-rich high-dimensional search space from solely sparse
visual reward signals significantly exacerbates the challenge of exploration.
The applicability of such systems is thus typically restricted to simulated or
heavily engineered environments since agent exploration in the real-world
without the guidance of explicit state estimation and dense rewards can lead to
unsafe behavior and safety faults that are catastrophic. In this study, we
isolate the root causes behind these limitations to develop a system, called
MoDem-V2, capable of learning contact-rich manipulation directly in the
uninstrumented real world. Building on the latest algorithmic advancements in
model-based reinforcement learning (MBRL), demo-bootstrapping, and effective
exploration, MoDem-V2 can acquire contact-rich dexterous manipulation skills
directly in the real world. We identify key ingredients for leveraging
demonstrations in model learning while respecting real-world safety
considerations -- exploration centering, agency handover, and actor-critic
ensembles. We empirically demonstrate the contribution of these ingredients in
four complex visuo-motor manipulation problems in both simulation and the real
world. To the best of our knowledge, our work presents the first successful
system for demonstration-augmented visual MBRL trained directly in the real
world. Visit https://sites.google.com/view/modem-v2 for videos and more
details.