Comparing Inertial Measurement Unit and Galvanic Skin Response Sensors Regarding Their Respective Abilities to Analyze Postural Instability
Open Access
- Author:
- Qazi, Gabrael
- Area of Honors:
- Industrial Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Andris Freivalds, Thesis Supervisor
Catherine Mary Harmonosky, Thesis Honors Advisor - Keywords:
- Healthcare
Ergonomics
Human Factors
IMU
GSR
Postural Instability - Abstract:
- With fall risk being a paramount health and ergonomic concern, the inertial measurement unit sensor (IMU) is an accurate, unobtrusive, and industry-standard choice for analysis of gait and postural instability. With features like an accelerometer, magnetometer, and gyroscope, the technology analyzes spatiotemporal balance at the body’s center of mass. Another sensor, the galvanic skin response sensor (GSR), is hypothesized to be a worthy alternative, as it measures skin conductance related to physiological status that could result from loss of balance. This study aims to conduct trials with GSR and IMU recorded simultaneously to understand if GSR is a valid measurement device for postural instability, conducting statistical inference and graphical analysis for verification. Data from seven subjects undergoing various standing tasks and eye conditions were analyzed. Acceleration data in the medial/lateral and anterior/posterior directions, as well as for skin conductance, were comparatively graphed. It was found that the standard deviation of tasks with eyes closed with single leg standing were highest, more so than eyes open and dual leg standing tasks. Analysis of variance (ANOVA) testing proved there was a statistically significant difference in means of standard deviation of tasks with eyes closed against all balance tasks regarding acceleration, but not skin conductance. In addition, similar testing proved that there was a statistically significant difference in means of standard deviation of tasks regarding eye condition and foot position for acceleration, but not skin conductance. Ultimately, comparing graphical data of both sensors and identifying volatility correlations was not consistent for changes in balance per subject. Overall, GSR was not a worthy alternative to IMU, nor was it an accurate device for measuring postural instability. Further study is recommended with upgraded sensors and statistical methods, as well as with more subjects.