Vibrotactile Sensory Feedback for Lower Limb Prostheses

Abstract

This dissertation focuses on understanding the limitations of a vibrotactile feedback system on the thigh. Due to the dynamic nature of the environment and time-sensitive information that need to be relayed to the user, it is important to know the strengths and weaknesses of implementing a vibrotactile system. Our data showed that vibrotactile stimuli does not provide the fastest reaction time when compared to visual and auditory stimuli. In addition, vibrotactile stimuli of the lower limb was most affected when walking was introduced. While investigating this issue, a systematic approach to understand human capability of spatially localizing perception was also developed. We found an interesting result that people were better at discriminating sensations mediolaterally than in the proximal/distal direction. Based on our results, the use of a sensory substitution system may not be feasible unless movements are predicted or time-sensitive information is not being communicated. However, the sensory effects of targeted muscle reinnervation could be leveraged to make a vibrotactile feedback system that provides natural feedback instead of using sensory substitution methods of feedback.