Supporting Spatial Awareness and Independent Wayfinding for Pedestrians with Visual Impairments
Rayoung Yang, Sangmi Park, Sonali R. Mishra, Zhenan Hong, Clint Newsom, Hyeon Joo, Erik Hofer, Mark W. Newman · 2011 · The Proceedings of the 13th International ACM SIGACCESS Conference on Computers and Accessibility (ASSETS) · doi:10.1145/2049536.2049544
Summary
This paper presents Talking Points 3 (TP3), a location- and orientation-aware smartphone system designed to increase the "legibility" of indoor environments for pedestrians with visual impairments, fostering spatial awareness rather than simply providing turn-by-turn directions. Drawing on Kevin Lynch's concept of environmental legibility — the ease with which people can form mental maps and orient themselves — TP3 represents the environment through five types of Points of Interest: paths (corridors, hallways), areas (food courts, lobbies), landmarks (stores, restaurants), decision points (intersections of paths), and functional elements (restrooms, stairs, elevators). Each POI includes physical characteristics descriptions (e.g., railings, counter shapes). The system uses GPS, WiFi, and compass positioning on an Android smartphone and provides three information retrieval mechanisms: Automatic Notifications (pushed when within 10 feet of a POI), Nearby Locations (list of POIs within 30 feet), and Directional Finder (point the phone in any direction to discover POIs within 100 feet in a 45-degree cone). All output is via text-to-speech, with simple one-handed gestures designed for users holding a cane or guide dog.
Key findings
Eight legally blind participants navigated three unfamiliar campus buildings using TP3 in a Wizard of Oz study (indoor positioning was simulated due to technical limitations). All participants completed task 1 successfully; tasks 2 and 3 had some failures but most participants found their destinations. Key findings went beyond basic wayfinding: participants used distance reports as a "Hot or Cold" game to confirm they were heading the right direction; TP3 enabled error recovery when participants took wrong turns by recognising they weren't receiving expected notifications; the Directional Finder was used nearly twice as much in open and complex environments compared to regular corridors; and participants developed distinct personalised navigation strategies — some used cardinal directions with the Directional Finder while others relied primarily on Automatic Notifications and waited for confirmation of proximity. Most significantly, TP3 enabled serendipitous discovery — participants learned about nearby resources (piano lounges, computer stations, restrooms) they would never have known about otherwise. Six of eight participants said TP3 would increase their travelling skill, and five felt it would give them a greater sense of independence. One participant noted that TP3 gave him information "Sighted guide[s] couldn't possibly tell you" and that with TP3, "I feel like it's in my control."
Relevance
This research makes an important conceptual contribution by reframing accessible navigation from efficient route-following to spatial awareness and environmental legibility. Most navigation systems for blind users focus on getting from A to B as quickly as possible, but TP3 demonstrates that spatial awareness — knowing what's around you, being able to explore and improvise — is what truly enables independence. The distinction is profound: turn-by-turn directions can actually reduce spatial awareness by encouraging passive compliance rather than active environmental understanding. For accessibility practitioners and navigation system designers, TP3's approach of combining push notifications (immediate relevance) with pull mechanisms (user-initiated exploration) offers a balanced model for information delivery. The finding that participants developed personalised strategies highlights the importance of flexible systems that support multiple navigation styles rather than imposing a single approach. The physical characteristics metadata (describing obstacles, counter shapes, railings) also points to information types that standard mapping databases lack but that are critical for safe independent travel.
Tags: blindness and low vision · wayfinding · indoor navigation · spatial cognition · mobile accessibility · independent living · navigation · situation awareness