MGuider: Mobile Guiding and Tracking System in Public Transit System for Individuals with Cognitive Impairments
Wei-Hsun Chen · 2009 · Proceedings of the 11th International ACM SIGACCESS Conference on Computers and Accessibility (Assets '09) · doi:10.1145/1639642.1639711
Summary
This paper presents MGuider, a mobile guiding and tracking system designed to help individuals with cognitive impairments navigate public transit systems independently. Developed in collaboration with NGOs running supported employment programs in Taipei, Taiwan, the system addresses the challenge that many people with cognitive disabilities — including those with traumatic brain injury, cerebral palsy, intellectual disability, schizophrenia, dementia, and Alzheimer's disease — struggle to travel independently on public transportation. Job coaches reported that their clients often needed to travel more than an hour using multiple transit modes, arriving two to three times before work to practice routes. The system uses a general-purpose PDA cell phone as the client device rather than a specialized assistive device, which keeps costs low and avoids the social stigma that research participants associated with dedicated assistive devices. MGuider leverages the extensive Wi-Fi access point infrastructure of the Taipei Mass Rapid Transit (MRT) system — over 1,000 APs across 68 stations — for indoor positioning, since GPS signals fail underground. The architecture includes GPS satellite positioning for outdoor tracking, Wi-Fi-based indoor positioning, a location database, web server, and SMS alert capabilities for caregivers.
Key findings
The system was evaluated with six participants recruited from five Taipei-based rehabilitation hospitals, with conditions including head injury and chronic mental illness. Four experimental conditions tested subjects with and without the PDA, comparing their ability to board correct trains and exit at correct stations. Results showed that most subjects found the system easy to operate, helpful for travel, and practical. Vibration prompts were found to be more effective than sound prompts for alerting users with mental illness. The system provided pop-up photos of stations, directional alerts when users went the wrong way, and vibration or sound notifications lasting three seconds when approaching their stop. An important design insight was that two of six participants were not cell phone users and initially disliked the PDA, though their resistance decreased after the experiment. Caregivers also received SMS alerts if users did not arrive on schedule, adding a safety layer.
Relevance
This early work demonstrates the potential of mainstream mobile technology to support independent living for people with cognitive disabilities, a theme that has become increasingly relevant with the ubiquity of smartphones. The decision to use a standard cell phone rather than specialized hardware reflects an important principle in assistive technology design: reducing stigma by leveraging devices people already carry. The finding about vibration versus sound prompts has practical implications for designing accessible notification systems. While the study is small (six participants) and the technology has evolved significantly since 2009, the core challenges it addresses — indoor wayfinding, caregiver peace of mind, and supporting employment independence — remain active areas of accessibility research and practice.
Tags: cognitive accessibility · wayfinding · mobile technology · public transit · assistive technology · supported employment · location-based services