Document Type



Summer 2021

Academic Department

Engineering and Physics

Faculty Advisor(s)

Dr. Mark Brinton


Prosthetic limbs provide individuals with amputations the ability to regain function in lost body parts. However, most prostheses are seen as tools rather than the embodiment of the user’s missing limb. To strengthen the connection between prosthesis and user, a sense of touch can be enabled via vibrotactile feedback. The goal of our experiment is to find the just-noticeable-difference (JND) in stimuli that an individual can distinguish while using two different waveforms: biomimetic and traditional. The biomimetic waveform mimics rapidly and slowly adapting receptors in the body by encoding rate-of-change in stimuli at the onset and offset of a more traditional 1.6 sec square wave. A graphical user interface was programmed in Matlab to control an Arduino Nano and an inexpensive coin vibrator. During the JND experiment, various pulse-wave-modulation (PWM) duty cycles were compared to a standard (58.8%) and the subject was asked to respond whether the first or second stimuli felt stronger. Although only pilot tests have been conducted, our data suggests that the biomimetic waveform yields a lower JND and could provide a more refined sense of touch. Future work includes integrating vibrators with a virtual hand for real-time sensory feedback.


Scholarship, Creative Arts, and Research Project (SCARP)