Blind echolocation using ultrasonic sensors

This paper proposes a navigation aid for the blind using echolocation principle and ultrasonic sensors. The device is for obstacles avoidance by detecting near objects in front of the user and shall trigger an audible alarm. Based on the echolocation principle, the ultrasonic beam is emitted in a certain direction in space through a transmitter. The beam is reflected from objects it encounters on its way; a matching receiver detects the reflected beam and the distance to the object is calculated based on time difference between emitting and receiving beam. Experimental results are presented. It could plausibly deduce that the device produced is suitable to be use as a navigation aid for the visually impaired.