Date of Award

Spring 5-2026

Language

English

Document Type

Honors Thesis

Degree Name

Bachelor of Arts

Department

Anthropology

Advisor/Committee Chair

John Polk

Committee Member

Sean Rafferty

Abstract

Falls among older adults are a leading cause of injury and loss of independence and have become an increasingly relevant public health issue as the elderly population continues to grow. Understanding the biomechanical factors that contribute to fall risk is essential in developing fall-prevention strategies and identifying individuals at risk. Force platforms are the gold-standard method for quantifying balance perturbations, but they are expensive and require dedicated lab space and support staff to operate. This research has three goals: (1) to test whether wearable accelerometers can provide similar discrimination of balance perturbations as a force plate, (2) to evaluate the effects of visual distortion and vision loss on static balance, and (3) to investigate different sensor locations (head, pelvis) for accelerometer-based balance assessment. In this study, 27 subjects were asked to wear triaxial accelerometers (Noraxon.com) on their forehead and posterior waist, and to stand on a force plate (AMTI.net) for 30 seconds. They performed this task (A) with their eyes open (normal, N), (B) while wearing vision-distorting goggles (drunkbusters.com) (DG), and with their eyes closed (EC). We obtained measures of antero-posterior (AP) and medio-lateral (ML) positions of the center of pressure on the force plate and linear accelerations for both head and pelvis accelerometers, and calculated root-mean-square measures of average COP movement and acceleration amplitude. We expected to see greater AP and ML accelerations and COP movement, when subjects wore goggles versus eyes closed versus when their eyes were open. We also expected to see smaller accelerations from the head sensor than the pelvis. Through analyzing the medio-lateral and anterior-posterior accelerations of the head and pelvis, along with center-of-pressure data from the force plate, we found the force plate to be more sensitive, as it detected significant differences between eyes closed versus eyes open and drunk goggles versus eyes open. The ML and AP accelerations trended in a similar direction to the force plate; however, they did not show significant differences in RMS accelerations across the three conditions. Head versus pelvis accelerations in DG, EC, and normal conditions were all found to be significantly different. The implications of these results are that accelerometer use may not be effective in detecting balance perturbations and analyzing fall risk for standing balance tasks. Additionally, there are implications to sensor placement, as head sensors may pick up movement that the pelvis does not.

Download

Share

COinS