A Careful Examination of Large Behavior Models for Multitask Dexterous Manipulation

Apr 15, 2026·
TRI LBM Team
,
Jose Barreiros
,
Andrew Beaulieu
,
Aditya Bhat
,
Rick Cory
,
Eric Cousineau
,
Hongkai Dai
,
Ching-Hsin Fang
,
Kunimatsu Hashimoto
,
Muhammad Zubair Irshad
,
Masha Itkina
,
Naveen Kuppuswamy
,
Kuan-Hui Lee
,
Katherine Liu
,
Dale McConachie
,
Ian McMahon
,
Haruki Nishimura
,
Calder Phillips-Grafflin
,
Charles Richter
,
Paarth Shah
,
Krishnan Srinivasan
,
Blake Wulfe
,
Chen Xu
,
Mengchao Zhang
,
Alex Alspach
,
Maya Angeles
,
Kushal Arora
,
Vitor Campagnolo Guizilini
,
Alejandro Castro
,
Dian Chen
,
Ting-Sheng Chu
,
Sam Creasey
,
Sean Curtis
,
Richard Denitto
,
Emma Dixon
,
Eric Dusel
,
Matthew Ferreira
,
Aimee Goncalves
,
Grant Gould
,
Damrong Guoy
,
Swati Gupta
,
Xuchen Han
,
Kyle Hatch
,
Brendan Hathaway
,
Allison Henry
,
Hillel Hochsztein
,
Phoebe Horgan
,
Shun Iwase
,
Donovon Jackson
,
Siddharth Karamcheti
,
Sedrick Keh
,
Joseph Masterjohn
,
Masayuki Masuda
,
Jean Mercat
,
Patrick Miller
,
Paul Mitiguy
,
Tony Nguyen
,
Jeremy Nimmer
,
Yuki Noguchi
,
Reko Ong
,
Aykut Onol
,
Owen Pfannenstiehl
,
Richard Poyner
,
Leticia Priebe Mendes Rocha
,
Gordon Richardson
,
Christopher Rodriguez
,
Derick Seale
,
Michael Sherman
,
Mariah Smith-Jones
,
David Tago
,
Pavel Tokmakov
,
Matthew Tran
,
Basile Van Hoorick
,
Igor Vasiljevic
,
Sergey Zakharov
,
Mark Zolotas
,
Rares Ambrus
,
Kerri Fetzer-Borelli
,
Benjamin Burchfiel
,
Hadas Kress-Gazit
,
Siyuan Feng
,
Stacie Ford
,
Russ Tedrake
· 0 min read
Large Behavior Models (LBMs) for multitask dexterous robot manipulation with rigorous evaluation pipeline.
Abstract
Robot manipulation has seen tremendous progress in recent years, with imitation learning policies enabling successful performance of dexterous and hard-to-model tasks. Concurrently, scaling data and model size has led to the development of capable language and vision foundation models, motivating large-scale efforts to create general-purpose robot foundation models. Although these models have garnered considerable enthusiasm and investment, meaningful evaluation of real-world performance remains a challenge, limiting the pace of development and inhibiting a nuanced understanding of current capabilities. Here, we rigorously evaluated multitask robot manipulation policies, referred to as large behavior models, by extending the diffusion policy paradigm across a corpus of simulated and real-world robot data. We proposed and validated an evaluation pipeline to rigorously analyze the capabilities of these models with statistical confidence. We compared against single-task baselines through blind, randomized trials in a controlled setting, using both simulation and real-world experiments. We found that multitask pretraining made the policies more successful and robust and enabled teaching complex new tasks more quickly, using a fraction of the data when compared with single-task baselines. Moreover, performance predictably increased as pretraining scale and diversity grows.
Publication
Science Robotics 11 (113), eaea6201