Term of Award

Summer 2019

Degree Name

Master of Science, Mechanical Engineering

Document Type and Release Option

Thesis (open access)

Copyright Statement / License for Reuse

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.


Department of Mechanical Engineering

Committee Chair

JungHun Choi

Committee Member 1

Biswanath Samanta

Committee Member 2

Minchul Shin


This study explores the ability to measure the changing impedance, ex vivo, of a porcine colon sample while undergoing a high-frequency alternating current from an Olympus PSD-30 electrosurgical unit and stop the applied current before excessive tissue damage ensues. The causes of the thermal damage are first examined, followed by the construction and testing of the impedance-controlled feedback device. Perforation was observed to occur when the impedance of the tissue sample increased by 25% or more. Using this information, the device was tested for five power settings ranging from 10W-50W. In each trial, the feedback device stopped the applied current to the tissue samples when the measured impedance exceeded the cut-off threshold of a 25% increase from the starting impedance. The device was found to have an accuracy of ±5Ω. This successfully minimized undue tissue damage and proved able to prevent serious complications such as perforation from occurring.

OCLC Number


Research Data and Supplementary Material