Prototype 3: Vibrotactile Belt
We attached six vibrators to a strip of elastic, held in place with a safety pin, and controlled all of them via separate pulse width modulation (PWM) channels on an Arduino microcontroller. This design was adjustable for children and adults of varying sizes. Even through clothes, subjects could discriminate low, medium and high intensities. They could easily detect movement around the belt but were not always able to localise the stimulation to a particular vibrator, sometimes confusing neighbouring motors.