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arXiv · 2510.20818

VAMOS: A Hierarchical Vision-Language-Action Model for Capability-Modulated and Steerable Navigation

Mateo Guaman Castro·Sidharth Rajagopal·Daniel Gorbatov·Matt Schmittle·Rohan Baijal·Octi Zhang·Rosario Scalise·Sidharth Talia·Emma Romig·Celso de Melo·Byron Boots·Abhishek Gupta
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Abstract

A fundamental challenge in robot navigation lies in learning policies that generalize across diverse environments while conforming to the unique physical constraints and capabilities of a specific embodiment (e.g., quadrupeds can walk up stairs, but rovers cannot). We propose VAMOS, a hierarchical VLA that decouples semantic planning from embodiment grounding: a generalist planner learns from diverse, open-world data, while a specialist affordance model learns the robot's physical constraints and capabilities in safe, low-cost simulation. We enabled this separation by carefully designing an interface that lets a high-level planner propose candidate paths directly in image space that the affordance model then evaluates and re-ranks. Our real-world experiments show that VAMOS achieves higher success rates in both indoor and complex outdoor navigation than state-of-the-art model-based and end-to-end learning methods. We also show that our hierarchical design enables cross-embodied navigation across legged and wheeled robots and is easily steerable using natural language. Real-world ablations confirm that the specialist model is key to embodiment grounding, enabling a single high-level planner to be deployed across physically distinct wheeled and legged robots. Finally, this model significantly enhances single-robot reliability, achieving 3X higher success rates by rejecting physically infeasible plans. Website: https://vamos-vla.github.io/

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Mateo Guaman Castro, Sidharth Rajagopal, Daniel Gorbatov, Matt Schmittle, Rohan Baijal, Octi Zhang, Rosario Scalise, Sidharth Talia, Emma Romig, Celso de Melo, Byron Boots, Abhishek Gupta. 2025-10-23. VAMOS: A Hierarchical Vision-Language-Action Model for Capability-Modulated and Steerable Navigation. https://arxiv.org/abs/2510.20818

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