Research advances of indoor navigation for blind people: A brief review of technological instrumentation

Blind persons need electronic traveling aid (ETA) solutions for better orientation and navigation in unfamiliar indoor environments, with embedded features for detection and recognition of both obstacles and desired destinations such as rooms, staircases, and elevators. Because the use of GPS for locational references is impractical indoors, the development of such navigation systems is challenging and requires a systematic review and evaluation of different technological approaches. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method, we evaluated and compared current research papers that deal with the prototyping of assistive devices (visual sensory perception substitution with audio and haptic signals) for blind and visually impaired persons. We conducted an instructional assessment of selected indoor navigation prototypes using three main criteria: navigation technologies, sensors, and computer vision approaches. For the latter category, we conducted a separate systematic review, as papers in this research area primarily specialize in software computer vision solutions rather than hardware. The paper provides useful insights for researchers regarding technological instrumentation for the development of ETA solutions for blind and visually impaired (VI) persons in the field of indoor orientation and navigation.