Real-time Measurements from Wearable Sensors to Enhance Stability on Uneven Terrain

Author

Sophie Copelin, University of Arkansas, FayettevilleFollow

Date of Graduation

5-2024

Document Type

Thesis

Degree Name

Bachelor of Science in Biomedical Engineering

Degree Level

Undergraduate

Department

Biomedical Engineering

Advisor/Mentor

Abbas, James

Committee Member

Asbee, Justin

Second Committee Member

Benigni, Tommaso

Abstract

The presented thesis is a study of sensation associated with inversion/eversion movement about the anterior/posterior axis. The long-term goal is to create a system that provides feedback to a prosthesis user, so their chances of falling is decreased. This feedback system would use wearable sensors to detect certain angles, so that sensory feedback could be provided. The study aimed to determine if Xsens Movella DOT sensors could be used in a system like this, so the accuracy of the Xsens Movella DOT sensors was assessed and the difference in angles that could be determined by them when compared to that of an unimpaired ankle was measured.

Sensor accuracy was verified using two other angle detection techniques, digital level measurement and right triangle trigonometry calculations. Plotting the sensors’ data relative to the trigonometry calculations resulted in almost a linear line of a slope near 1.

The just noticeable difference (JND) about 0° was calculated for three participants. The JND ranged from 1.2° to 2.1°, and the average JND was 1.64°, which is considerably more than any detected inaccuracies in the sensors. Consequently, further study of using wearable sensors to establish a feedback system to improve stability for lower limb prostheses users is warranted.

In the future, testing the JND about other degrees, other than 0°, will take place to determine if sensitivity is different at other ankle positions, and the protocol used in this study will be improved with more particpants and a better understanding of how to find and calculate the JND.

Keywords

Prosthesis; Feedback System; Wearable Sensors; Just Noticeable Difference; Movella; ankle movement

Citation

Copelin, S. (2024). Real-time Measurements from Wearable Sensors to Enhance Stability on Uneven Terrain. Biomedical Engineering Undergraduate Honors Theses Retrieved from https://scholarworks.uark.edu/bmeguht/154