In 2000, 4 WPI students built a $400-per-intersection system to help blind pedestrians find crosswalk buttons. 26 years later, locator tones are standard features of accessible pedestrian signals across U.S. cities

In 2000, Worcester Polytechnic Institute students developed the “Crosswalk Button Locator,” a low-cost system designed to help blind and visually impaired pedestrians find crosswalk buttons independently. The project began after Larry Raymond, Worcester’s assistant director of human resources and a blind guide-dog user, approached WPI for help solving the problem.