The RAD: Making Racing Games Equivalently Accessible to People Who Are Blind

We introduce the racing auditory display (RAD), an audio-based user interface that allows players who are blind to play racing games with a similar efficiency and sense of control as sighted players can. The RAD comprises two novel sonification techniques: the sound slider for understanding a car's speed and trajectory on a racetrack and the turn indicator system for alerting players of the direction, sharpness, length, and timing of upcoming turns. In a user study with 15 participants (3 blind; the rest blindfolded and analyzed separately), we found that players preferred the RAD's interface over that of Mach 1, a popular blind-accessible racing game. We also found that the RAD allows an avid gamer who is blind to race as well on a complex racetrack as casual sighted players do. When that gamer raced using the RAD, there was no significant difference between his lap times or driving paths compared to those of players racing with sight.