Can electrical pulses be adapted to create life-like perceptions?

Abstract: The next big step to improve prosthetics and make the lives of people living with certain physical disabilities less restricted is to provide them with sensory feedback. Today most feedback systems used in prosthetics are mechanical but with the recent developments in sensors and the processing of their input electrical stimulation is becoming an increasingly promising way to convey touch, pressure and movement. This thesis investigated the effect of five parameters on the characteristics of the sensations generated by electrical stimulation of the hand nerves using transcutaneous electrodes. Two pulses were used, a small and long pre-pulse in combination with a large and short main pulse. Their amplitudes, durations and the frequency of the stimulation were used to create different combinations that were used to explore how each parameter affects the resulting sensation. The results show that what type of sensation is generated and if it is felt on the surface of the skin or deeper within the hand is easily affected by adapting the stimulations parameters. How natural the feeling was and where on the hand it appears is more complicated but can be somewhat influenced by changing these parameters. They also imply that another pulse under the perception threshold before the main pulse or having multiple pulses might affect the results in a different way than just changing the size of one pulse.