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Date of Award
Doctor of Philosophy (PhD)
Sophisticated motorized prosthetic limbs contain multiple degrees of freedom of motion as well as embedded pressure and angle transducers to provide sensory feedback in amputees. Although several central neural recording and stimulation modalities exist for both controlling these motions and providing sensory feedback from a prosthetic limb, directly interfacing the peripheral nerves which originally innervated the limb has many advantages. A difficulty with this bi-directional approach is that electrically stimulating axons to provide haptic feedback creates stimulation artifacts at neighboring recording sites within the nerve that are several orders of magnitude larger than the electroneurogram used for control. In this dissertation, a novel micro-channel sieve electrode is designed, optimized and tested that can provide true bi-directional and concurrent electrical stimulation to sensory axons while simultaneously recording high-fidelity electroneurograms from motor axons in the same peripheral nerve. This research, through computational modeling, compares the concurrent bi-directional performance of both the novel micro-channel sieve electrode designed in this dissertation and the gold standard intrafascicular electrode (tfTIME) used in current clinical research studies in human amputees. The novel micro-channel sieve electrode was found to significantly outperform the tfTIME electrode by increasing recording levels and decreasing stimulation artifact yielding a signal to artifact ratio greater than 50 dB compared to -56.4 dB for the tfTIME. The novel micro-channel sieve electrode developed in this dissertation could provide the first concurrentl, bi-directional peripheral nerve interface for clinical applications.
Daniel K. Moran
Dennis Barbour, Wilson Ray, Matthew Wood, Shantanu Chakrabartty,
Available for download on Wednesday, January 02, 2019