Alireza Sedighi1, Elaheh Rashedi2, Maury A Nussbaum3. 1. Bone and Joint Center, Department of Orthopaedic Surgery, Henry Ford Hospital, Detroit, Michigan, 48202, USA. Electronic address: asedigh1@hfhs.org. 2. Bone and Joint Center, Department of Orthopaedic Surgery, Henry Ford Hospital, Detroit, Michigan, 48202, USA. 3. Industrial and Systems Engineering, Virginia Tech, Blacksburg, 24061, USA.
Abstract
BACKGROUND: Head-worn displays (e.g., "smart glasses") are an emerging technology to provide information, and in many situations they might be used while walking. However, little evidence exists regarding the effects of head-worn displays on walking performance. We found earlier that "smart glasses" had smaller adverse effects on measures of gait variability in the anterior-posterior direction vs. other types of information displays. Participants, however, complained about motion sickness and perceived instability while using smart glasses. RESEARCH QUESTION: Were the participants' complaints a result of adverse effects of the smart glasses on the dynamics of lateral stepping and gait stability? METHODS: Twenty individuals walked on a treadmill in four different conditions; single-task walking, and three dual-task walking conditions, the latter using smart glasses, smartphone, and a paper-based system to provide secondary cognitive tasks. We assessed the dynamics of lateral stepping and gait stability using the goal equivalent manifold and maximum Lyapunov exponent, respectively. RESULTS: The dynamics of the lateral stepping were more adversely affected using smart glasses compared to the other types of information displays. However, stability measures revealed that the participants were more unstable when they used the smartphone and paper-based system. SIGNIFICANCE: Promising results in terms of stability and adaptability suggest that head-worn display technology is a potentially useful alternative to smartphones and other types of information displays for reducing the risk of a fall. Results regarding perceptions of instability and a loss of control over lateral stepping, however, imply that this technology requires further development prior to real-work implementations.
BACKGROUND: Head-worn displays (e.g., "smart glasses") are an emerging technology to provide information, and in many situations they might be used while walking. However, little evidence exists regarding the effects of head-worn displays on walking performance. We found earlier that "smart glasses" had smaller adverse effects on measures of gait variability in the anterior-posterior direction vs. other types of information displays. Participants, however, complained about motion sickness and perceived instability while using smart glasses. RESEARCH QUESTION: Were the participants' complaints a result of adverse effects of the smart glasses on the dynamics of lateral stepping and gait stability? METHODS: Twenty individuals walked on a treadmill in four different conditions; single-task walking, and three dual-task walking conditions, the latter using smart glasses, smartphone, and a paper-based system to provide secondary cognitive tasks. We assessed the dynamics of lateral stepping and gait stability using the goal equivalent manifold and maximum Lyapunov exponent, respectively. RESULTS: The dynamics of the lateral stepping were more adversely affected using smart glasses compared to the other types of information displays. However, stability measures revealed that the participants were more unstable when they used the smartphone and paper-based system. SIGNIFICANCE: Promising results in terms of stability and adaptability suggest that head-worn display technology is a potentially useful alternative to smartphones and other types of information displays for reducing the risk of a fall. Results regarding perceptions of instability and a loss of control over lateral stepping, however, imply that this technology requires further development prior to real-work implementations.