Deploy and Test a Smartphone Based Accessible Traffic Information System for the Visually Impaired
Chen-Fu Liao, Senior Systems Engineer, Mechanical Engineering
An increasing number of Accessible Pedestrian Signals (APS) have been installed at new or upgraded intersections to assist people with vision impairment to navigate streets. For un-signalized intersections and intersections without APS, people with vision impairment have to rely on their own orientation and mobility skills to gather necessary information to navigate to their destinations. Previously, a smartphone-based accessible pedestrian system was developed to support wayfinding and navigation for people with vision impairment at both signalized and un-signalized intersections. A digital map was also created to support the wayfinding app. This system allows a visually impaired pedestrian to receive signal timing and intersection geometry information from a smartphone app for wayfinding assistance. A beacon using Bluetooth Low Energy (BLE) technology was also developed to help identify a pedestrian's location when he or she is traveling in a GPS-unfriendly environment. A network of Bluetooth beacons ensures that correct traffic information is provided to the visually impaired at the right location. This project is leveraging the previous development by installing this system at a number of intersections in downtown Stillwater, where MnDOT operates the signalized intersections. Researchers interface with the traffic controllers to broadcast traffic signal phasing and timing (SPaT) information through a secured and private wireless network for the visually impaired users. The aim is to test the smartphone-based accessible system and evaluate the effectiveness and usefulness of the system in supporting their wayfinding and navigation while traveling through signalized and un-signalized intersections.