Accessible Pedestrian Signal

A device integrated into pedestrian signal systems at traffic intersections that communicates walk and don't-walk information to pedestrians who are blind or have low vision through audible tones, verbal messages, vibrotactile surfaces, or a combination of these. APS devices typically emit a locator tone to help pedestrians find the pushbutton, followed by a distinct walk indication sound. While APS significantly improves intersection safety for visually impaired pedestrians, many intersections still lack them, creating a need for smartphone-based alternatives like walk-light detector apps that use computer vision to identify signal states. The US Access Board and the Manual on Uniform Traffic Control Devices (MUTCD) provide standards for APS installation.