Ultrasonic sonar for the blind and visually impaired

This article is intended to show how to build and use an accessibility device I’ve designed to assist people who are at various levels of visual impairment. The idea behind the device is to use an ultrasonic range-finder sensor, and translate its reading into an audible indication of distance of objects up to 4 meters away, thereby giving a person who is visually impaired a better sense of their immediate surroundings. Aside from the utility of the device, several other key features of the device include that it is wearable, has a long battery life, is fairly light-weight, and is built from rather inexpensive parts.”