The Effects of a Visual Distance Feedback Device on Rollator Walker Position and User Posture: A Validation Study

Date of Award


Degree Name

M.S. in Mechanical Engineering


Department of Mechanical Engineering


Advisor: Kimberly Bigelow


A biofeedback device, known as a position monitor, was designed to encourage rollator walker users to ambulate closer to their walker by means of visual feedback. An LED on the device was programmed to illuminate green when the participants were within a set threshold, and red when they were standing outside of that threshold. The efficacy of this device was investigated by monitoring 14 rollator walker users between the ages of 77 and 94 ambulate with their walker with and without the device in varying conditions. The participants completed three 10 Meter Walk trials with and without feedback and one 8 meter obstacle trial, consisting of thresholds and cones, with and without feedback. During feedback trials participants were encouraged by the device to ambulate 10% closer than their average habitual distance from the walker without device feedback. Throughout all trials, participants distance from the walker crossbar was being recorded by an ultrasonic sensor onto a micro SD card, and their body kinematics were being recorded by the Xsens Awinda Biomech suit of inertial sensors. Results demonstrated that individuals were able to attend and appropriately respond to the feedback from the device in both the ideal environment (10 Meter Walk) and while navigating environmental obstacles such as would be commonly faced during every day ambulation (obstacle course). During the 10 Meter Walk when feedback was provided, individuals spent on average 89.47±5.89 percent of their time below the threshold and significantly decreased their average distance from their walker by an average of approximately 11cm (p=0.000). During the obstacle when feedback was provided, individuals spent on average 67.35 ± 20.98 percent of the trial time below the threshold, and significantly decreased their average distance by an average of approximately 15 cm (p=0.000). The primary methods for attending to the device was a decrease in shoulder flexion. This adaptation was found to be statistically significant in both the 10 Meter Walk and obstacle course, with p-values of 0.001 and 0.000 respectively. The device was not found to substantially improve posture as defined by trunk inclination. The efficacy of the position monitor to encourage rollator walkers to ambulate at a closer distance to their walking frame was validated in this study. By ambulating closer to their device individuals are able to maximize their margin of stability by maintaining the location of their center of mass well within the base of support of the walker. This closer ambulating distance encouraged by the device also allows for more downward force production on the handles, which may result in overall improved walker stability.


Biomedical Engineering, Biomechanics, Engineering, Physical Therapy, Mechanical Engineering, Rollator Walker, Walker Biomechanics, Walker Stability, Walker Distance, Walker Biofeedback

Rights Statement

Copyright 2018, author