Indoor Navigation by People with Visual Impairment Using a Digital Sign System

TLDR

There is a need for adaptive technology to enhance indoor wayfinding by visually‑impaired people. The study develops and tests a Digital Sign System to improve indoor navigation for visually‑impaired users. The system uses digitally‑encoded signs, an infrared‑camera handheld reader, image‑processing software, and a talking digital map on a mobile device, and was evaluated with blind, low‑vision, blindfolded sighted, and normally sighted participants across three navigation tasks. The prototype reliably retrieves sign information during active mobility, helps users locate points of interest, and enables route following; visually impaired participants completed tasks accurately and independently, though slower than controls, demonstrating feasibility of independent indoor navigation.

Abstract

There is a need for adaptive technology to enhance indoor wayfinding by visually-impaired people. To address this need, we have developed and tested a Digital Sign System. The hardware and software consist of digitally-encoded signs widely distributed throughout a building, a handheld sign-reader based on an infrared camera, image-processing software, and a talking digital map running on a mobile device. Four groups of subjects—blind, low vision, blindfolded sighted, and normally sighted controls—were evaluated on three navigation tasks. The results demonstrate that the technology can be used reliably in retrieving information from the signs during active mobility, in finding nearby points of interest, and following routes in a building from a starting location to a destination. The visually impaired subjects accurately and independently completed the navigation tasks, but took substantially longer than normally sighted controls. This fully functional prototype system demonstrates the feasibility of technology enabling independent indoor navigation by people with visual impairment.