SSR: Scaling Surefooted and Symmetric Humanoid Traversal to the Open World

2026-05-28

AI Summary

This work addresses the challenge of enabling safe, natural, vision-driven locomotion for humanoid robots in open-world environments, where dynamic movement over complex terrain demands stable foot placement and full-body coordination. The authors propose SSR, an end-to-end framework that jointly learns foot placement policies and whole-body motion directly from visual inputs. Key innovations include an imagined foothold guidance mechanism to enhance stability, an equivariant latent space with symmetry augmentation to promote bilateral coordination, and terrain-aware multi-discriminator motion priors to generate human-like behaviors. Relying solely on high-dimensional visual observations, the method achieves safe, stable, and high-quality long-horizon outdoor walking across real-world challenging terrains, including heterogeneous stairs, wide gaps, and elevated platforms.

Abstract

Extending humanoid traversal to the open world is key to practical deployment in human environments, but remains challenging. The robot must use vision to ensure safe and reliable foot placement on heterogeneous terrain under highly dynamic motion, while producing coordinated, natural whole-body behaviors. We propose SSR, an efficient end-to-end framework for egocentric vision-based humanoid traversal that jointly learns these capabilities. SSR introduces imagined foothold guidance, which learns to model forthcoming swing-foot contacts and evaluates their support to guide pre-touchdown swings toward stable regions, reducing edge slips. It further employs equivariant latent-space symmetry augmentation to efficiently induce bilateral coordination under high-dimensional visual observations, and uses terrain-specific multi-discriminator motion priors to encourage human-like behavior across scenes. Extensive experiments show that SSR achieves safe, stable, and high-quality locomotion on diverse real-world terrains, including stairs with varied structures and extreme challenges such as wide gaps and high platforms, while enabling reliable long-horizon traversal in open outdoor environments.

Problem

• humanoid locomotion
• open-world traversal
• vision-based control
• foot placement
• terrain adaptation

Innovation

• imagined foothold guidance
• equivariant latent-space symmetry augmentation
• multi-discriminator motion priors
• egocentric vision-based locomotion
• humanoid traversal