SignLoc: Robust Localization using Navigation Signs and Public Maps

TL;DR

SignLoc is a novel localization approach that uses navigation signs and public maps to achieve robust robot localization without prior mapping, demonstrated across various large-scale environments.

Contribution

It introduces a probabilistic method leveraging signs and maps for global localization without prior sensor-based mapping, applicable to diverse environments.

Findings

Reliable localization after observing only one or two signs

Effective in large-scale environments like campuses and malls

Operates without prior sensor-based mapping

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.