FORGE: Force-Guided Exploration for Robust Contact-Rich Manipulation under Uncertainty

1Massachusetts Institute of Technology 2University of Southern California 3NVIDIA Research

FORGE policies enable multi-stage assembly of a planetary gearbox.

Abstract

We present FORGE, a method that enables sim-to-real transfer of contact-rich manipulation policies in the presence of significant pose uncertainty. FORGE combines a force-threshold mechanism with a dynamics randomization scheme during policy learning in simulation, to enable the robust transfer of the learned policies to the real robot. At deployment, FORGE policies, conditioned on a maximum allowable force threshold, adaptively perform contact-rich tasks while respecting the specified force threshold, regardless of the controller gains. Additionally, FORGE autonomously predicts a termination action, once the task has succeeded. We demonstrate that FORGE can be used to learn a variety of robust contact-rich policies, enabling multi-stage assembly of a planetary gear system, which requires success across three assembly tasks: nut-threading, insertion, and gear meshing.

FORGE is evaluated on three contact-rich tasks: Peg Insertion, Gear Meshing, and Nut Threading.

Project Video

Acknowledgements

This research was sponsored in part by Army Research Labs under the A2I2 program and by NVIDIA. Their support is gratefully appreciated.