The people sensor: a mobility aid for the visually impaired

Electronic Travel Aids, which transform visual environmental cues into another sensory modality, have been proven to help visually impaired people travel with a greater degree of psychological comfort and independence. The People Sensor is an Electronic Travel Aid designed to address two issues of importance to visually impaired people: inadvertent cane contact with other pedestrians and objects, and speaking to a person who is no longer within hearing range. The device uses pyroelectric and ultrasound sensors to locate and differentiate between animate (human) and inanimate (non-human) obstructions in the detection path. The distance between the user and the obstruction along with the nature of the obstruction (human or non-human) is transmitted via modulated vibrotactile feedback. Armed with advance knowledge of the presence and location of objects and people in the environment, users of The People Sensor can travel with increased independence, safety and confidence.