Sonar for the Visually Impaired

Quan, Matthew

This project studies the effectiveness a device that the visually impaired may use in place of a blind cane to detect physical obstructions such as chair legs and tables. In the past many visually impaired have used white tipped canes to detect objects in their surroundings. But, the problem with the canes is they cannot be used to detect elevated objects such as a chair. The device constructed consists of a sonar sensor coupled to an Arduino Uno Prototyping Board. Sensory data was interpreted to the user via pulses from a TENS unit (Transcutaneous electrical nerve stimulation). This is the first recorded device that uses a TENS unit to interpret sensory data. For this experiment test subjects walked towards the various sides of a chair and a face of a wall with a sonar device connected to their arm. They were asked to stop when they could feel a pulse in their arm that was created by small electrical pulses that came from a TENS unit. The results show that the TENS unit was able to transmit the sensory data to the test subjects well. The front of the chair had a 96% detection rate. The back of the chair had a 92% detection rate. The side of the chair had a 46% detection rate, and the wall had an 84% detection rate.