[2603.03546] Real-time loosely coupled GNSS and IMU integration via Factor Graph Optimization

Computer Science > Robotics arXiv:2603.03546 (cs) [Submitted on 3 Mar 2026] Title:Real-time loosely coupled GNSS and IMU integration via Factor Graph Optimization Authors:Radu-Andrei Cioaca, Cristian Rusu, Paul Irofti, Gianluca Caparra, Andrei-Alexandru Marinache, Florin Stoican View a PDF of the paper titled Real-time loosely coupled GNSS and IMU integration via Factor Graph Optimization, by Radu-Andrei Cioaca and 5 other authors View PDF HTML (experimental) Abstract:Accurate positioning, navigation, and timing (PNT) is fundamental to the operation of modern technologies and a key enabler of autonomous systems. A very important component of PNT is the Global Navigation Satellite System (GNSS) which ensures outdoor positioning. Modern research directions have pushed the performance of GNSS localization to new heights by fusing GNSS measurements with other sensory information, mainly measurements from Inertial Measurement Units (IMU). In this paper, we propose a loosely coupled architecture to integrate GNSS and IMU measurements using a Factor Graph Optimization (FGO) framework. Because the FGO method can be computationally challenging and often used as a post-processing method, our focus is on assessing its localization accuracy and service availability while operating in real-time in challenging environments (urban canyons). Experimental results on the UrbanNav-HK-MediumUrban-1 dataset show that the proposed approach achieves real-time operation and increased service avai...