Design and evaluation of iCalm : a novel, wrist-worn, low-power, low-cost, wireless physiological sensor module

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (p. 151-156).The impracticality of the ambulatory electrocardiogram for long-term physiological monitoring has lead to the development of many new, compact sensors that have been designed with form factor and user comfort in mind. Nevertheless, there currently is no single sensor module that would be ideal to use for continuous, long-term monitoring. The sensors tend to either lack wireless capabilities, have a short battery life, or are financially unfeasible. After conducting a quick survey of recently developed sensors, we propose the design of iCalm: a novel, wrist-worn, low-power, low-cost, and wireless physiological sensor module. Its performance is compared against an FDA-approved platform through numerous experiments, including a few user studies. The iCalm skin conductance sensor greatly reduced noise due to motion and pressure artifacts; the iCalm heart rate sensor performed similar to the FDA-approved sensor. In addition, all of the participants in the experiments preferred the iCalm to the FDA-approved comparison sensors we tested. With iCalm, we hope to enable comfortable, long-term monitoring of the autonomic nervous system physiology and improve upon the current commercial sensors on the market.by Hoda Eydgahi.S.M