An alternative mobility aid for the blind: the `ultrasonic cane´

A design of a small portable electronic cane utilizing Polaroid´s Ultrasonic Ranging Unit intended to supplement or replace the traditional long cane is presented. A prototype was fitted in a flashlight-like enclosure made of a PVC tube with an external battery pack as power supply and an ear-plug, for the audible output. Preliminary testing of the prototype with two blind individuals shows that some minor circuit adjustments for filter response time and audible output frequency range had to be made. Other than that, after a brief training period, blind people could get around easily using the device. Some problems still occur when people encounter staircases, which can be circumvented if a long cane is used in conjunction with the ultrasonic cane or if a more extensive training period is administered. In general, the initial results indicate that the users found that their perception of their environment was enhanced by using the ultrasonic cane