Hand-Mounted Sonar For the Blind

GeekTech.in writes "The Tacit, a wrist-mounted sonar device with haptic feedback, is like strapping a bat to your wrist to help you see. It makes use of two sonar ping sensors to measure the distance to the nearest obstacle. The relative distance to an object is then fed back to the user using two servos which apply pressure to the back of the wrist."