%0 Journal Article
%T Seamless Fusion: Multi-Modal Localization for First Responders in Challenging Environments.
%A Dahlke D
%A Drakoulis P
%A Fernández García A
%A Kaiser S
%A Karavarsamis S
%A Mallis M
%A Oliff W
%A Sakellari G
%A Belmonte-Hernández A
%A Alvarez F
%A Zarpalas D
%J Sensors (Basel)
%V 24
%N 9
%D 2024 Apr 30
%M 38732970
%F 3.847
%R 10.3390/s24092864
%X In dynamic and unpredictable environments, the precise localization of first responders and rescuers is crucial for effective incident response. This paper introduces a novel approach leveraging three complementary localization modalities: visual-based, Galileo-based, and inertial-based. Each modality contributes uniquely to the final Fusion tool, facilitating seamless indoor and outdoor localization, offering a robust and accurate localization solution without reliance on pre-existing infrastructure, essential for maintaining responder safety and optimizing operational effectiveness. The visual-based localization method utilizes an RGB camera coupled with a modified implementation of the ORB-SLAM2 method, enabling operation with or without prior area scanning. The Galileo-based localization method employs a lightweight prototype equipped with a high-accuracy GNSS receiver board, tailored to meet the specific needs of first responders. The inertial-based localization method utilizes sensor fusion, primarily leveraging smartphone inertial measurement units, to predict and adjust first responders' positions incrementally, compensating for the GPS signal attenuation indoors. A comprehensive validation test involving various environmental conditions was carried out to demonstrate the efficacy of the proposed fused localization tool. Our results show that our proposed solution always provides a location regardless of the conditions (indoors, outdoors, etc.), with an overall mean error of 1.73 m.