Linechaser: A smartphone-based navigation system for blind people to stand in lines

Abstract

Standing inof line is one the most commonso cial behaviors in public spaces but can be challenging for blind people. We propose an assistive system named LineChaser, which navigates a blind user to the end of a line and continuously reports the distance and direction to the last person in the line so that they can be followed. LineChaser uses the RGB camera in a smartphone to detect nearby pedestrians, and the built-in infrared depth sensor to estimate their position. Via pedestrian position estimations, LineChaser deter- mines whether nearby pedestrians are standing in line, and uses audio and vibration signals to notify the user when they should start/stop moving forward.Inthisway,userscanstaycorrectly positioned while maintaining social distance. We have conducted a usability study with 12 blind participants. LineChaser allowed blind participants to successfully navigate lines, signifcantly increasing theirconfdenceinstandinginlines.