cs.ROSep 26, 2026

An Empirical Study on What Matters for Viewpoint-Generalizable Policies in Visual Imitation Learning

Authors: Mino Nakura, Sriram Krishna, Yufei Wang, Shubham Tulsiani, Zackory Erickson, David Held

Organizations: Robotics Institute, Carnegie Mellon University, Pittsburgh, PA 15213, USA.

Abstract

Visual imitation learning is a promising approach to training robot manipulation policies capable of completing a wide variety of tasks. However, policies today remain brittle to viewpoint perturbations, making deployment in diverse environments a challenge. We present a controlled empirical study of which design choices allow visuomotor policies to generalize across viewpoints. We find that viewpoint generalization improves when dense visual tokens are retained and the action head participates in geometric reasoning. On a suite of simulated tasks that span a wide range of camera poses, we show that these design choices yield a policy that remains performant across viewpoints. As a practical consequence, a policy trained with these design choices also transfers zero-shot from simulation to the real world under random camera configurations.

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