Accessible Traffic Signals for Blind and Visually Impaired Pedestrians

Principal Investigator(s):

Chen-Fu Liao, Former Researcher, Mechanical Engineering


Project summary:

Blind and visually impaired pedestrians often travel in areas that are unfamiliar to them and cross at signalized intersections. Locating the sidewalk and the pushbutton of a desired crossing direction are among the most difficult tasks for blind pedestrians to cross a street. The chirping sound and audible messages from traditional Accessible Pedestrian Signal (APS) systems are often confused with other noises in the vicinity of an intersection. The goal of this project is to provide effective traffic signal information and guidance while crossing the intersection to blind and visually impaired pedestrians. The researchers are developing a mobile APS system by using the Global Positioning System (GPS), Text to Speech (TTS), and cell phone technologies. The researchers aim to take advantage of several components from previous research studies and investigate the feasibility of integrating these technologies in order to develop a reliable and effective methodology for determining the location of a blind cell phone user on the street with respect to an intersection. Intersection information and signal states (for example, the "walk" or "don't walk" message) can then be broadcast to blind cell phone users wirelessly from the signal controller. The traffic information can then be translated into audible messages using commercially available TTS technology. This approach will provide options to allow blind and visually impaired pedestrians to subscribe to and receive personal assistive traffic signal information while waiting to cross and while crossing an intersection.


Project details: