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arXiv · 2508.18606

SignLoc: Robust Localization using Navigation Signs and Public Maps

Nicky Zimmerman·Joel Loo·Ayush Agrawal·David Hsu
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Abstract

Navigation signs and maps, such as floor plans and street maps, are widely available and serve as ubiquitous aids for way-finding in human environments. Yet, they are rarely used by robot systems. This paper presents SignLoc, a global localization method that leverages navigation signs to localize the robot on publicly available maps -- specifically floor plans and OpenStreetMap (OSM) graphs -- without prior sensor-based mapping. SignLoc first extracts a navigation graph from the input map. It then employs a probabilistic observation model to match directional and locational cues from the detected signs to the graph, enabling robust topo-semantic localization within a Monte Carlo framework. We evaluated SignLoc in diverse large-scale environments: part of a university campus, a shopping mall, and a hospital complex. Experimental results show that SignLoc reliably localizes the robot after observing only one to two signs.

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Nicky Zimmerman, Joel Loo, Ayush Agrawal, David Hsu. 2025-08-26. SignLoc: Robust Localization using Navigation Signs and Public Maps. https://arxiv.org/abs/2508.18606

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