Vertex: A Semantic Graph-Based Indoor Navigation System with Vision-Language Landmark Verification

[EN] Older adults often need guidance when visiting new buildings for the first time. However, indoor navigation remains challenging due to the lack of Global Positioning System (GPS) availability, visually repetitive corridors, and frequent location failures. This article presents a multimodal indo...

Descripción completa

Detalles Bibliográficos
Autores: Ferri-Molla, Isabel|||0009-0008-3608-9891, Silvestre Cerdà, Joan Albert|||0000-0003-2291-8296, Bazazian, Dena, Varga, Marius N., Linares-Pellicer, Jordi
Tipo de recurso: artículo
Fecha de publicación:2026
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:dnet:riunet______::0dd68c2fdf1bcaf518d1069f493adabb
Acceso en línea:https://riunet.upv.es/handle/10251/236053
Access Level:acceso abierto
Palabra clave:Augmented reality
Indoor navigation
Infrastructure-free localisation
Multimodal interaction
Older adults
Semantic graph
Spatial anxiety
Vision language models
Visual verification
03.- Garantizar una vida saludable y promover el bienestar para todos y todas en todas las edades
10.- Reducir las desigualdades entre países y dentro de ellos
11.- Conseguir que las ciudades y los asentamientos humanos sean inclusivos, seguros, resilientes y sostenibles
Descripción
Sumario:[EN] Older adults often need guidance when visiting new buildings for the first time. However, indoor navigation remains challenging due to the lack of Global Positioning System (GPS) availability, visually repetitive corridors, and frequent location failures. This article presents a multimodal indoor navigation assistant that combines graph-based route planning with visual landmark verification to provide step-by-step guidance. The environment is modelled as a directed graph whose nodes are annotated with semantic landmarks, and the graph is constructed primarily from a video of the building, reducing the need for 3D scanners, beacons, or other specialised instruments. Routes are calculated using Dijkstra¿s shortest-path algorithm over the semantic graph. During navigation, camera frames are analysed using a restricted vision-language recognition strategy that only considers candidate landmarks from the current and next nodes, reducing false detections and improving interpretability. To increase robustness, a temporary voting mechanism was introduced to confirm node transitions, as well as a hierarchical redirection strategy with local and global recovery. The system is implemented in two modes: handheld mode with visual cues using augmented reality arrows, mini map and voice instructions, and hands-free mode with front camera using voice instructions and keywords. Evaluation involved preliminary technical testing in the United Kingdom followed by formal user validation in Spain. During these trials, participants reported high usability, strong confidence and safety, and increased perceived independence.