Jennifer Deignan

Wearable chemical sensors: Characterization of heart rate electrodes using electrochemical impedance spectroscopy

A series of experiments was conducted in order to determine the reaction kinetics of various types of heart rate monitoring electrodes. In addition, nonmotion on-body measurements were performed in order to gauge how the difference in reaction kinetics translates to the electrocardiogram signal. Standard solid-gel Ag/AgCl single use monitoring electrodes are used here as the gold standard to which textile electrodes can be compared. The test method created here will serve as a basis to evaluate future heart rate monitoring electrodes.

Textile piezoresistive sensors for on-body measurement of spinal extension

Here we investigate the feasibility of textile based piezoresistive sensors to accurately measure increases in spinal extension, on-body for clinical application in the Modified Modified Schobers test. The proposed sensor combines the accuracy of standard metallic strain sensors with the comfort and usability of textiles, offering innumerable wearable applications. Calibration testing of the textile sensors showed a linear dependency between sensors electrical resistance and strain in the region of interest (25-60% strain) with great reproducibility (relative standard deviation 0.0296-2.04%, n=10). On-body testing of the device has shown accurate results validated by standard measurements done with a steel measuring tape, proving the viability of the sensor for real-time monitoring of spinal extension.