JMIR Publications

ABSTRACT

The human walking balance is achieved and maintained by a complex set of human sensorimotor and musculoskeletal systems that control vision, proprioception, vestibular function, muscle contraction, and more. The elements of walking can be used for measurement in healthy and pathological subjects, and is used to diagnose disorders related to the nervous system. This study presents a new approach to measure and analyze the walking balance of human subjects using motion sensors in a smart phone. We developed a mobile health (mHealth) application to collect the coordinate of gyroscope, rotation matrix and coordinate of accelerometer and so on, of which this study used rotation matrix to compare the walking balance among the human subjects. Rotation vector, calculated by rotation matrix, was used to measure the pitch, roll and yaw angles of the human body while walking using the smartphone worn in the middle of waistline (as the center of gravity). Data was collected from three subjects including two healthy individuals (one female and one male) and one male with back pain caused from an over-strenuous workout. The male experiencing back pain injured his back during exercise but does not have any issues walking. The participants were wearing the smartphone in the middle of waistline while walking. The male with back pain exhibited a diminished level of walking balance with a wider range of variation than the other subjects. While this study tested the mHealth application with only three subjects, it showed that the new method effectively monitored their postural balance while walking. Our mHealth system can be implemented in mobile devices for supporting clinical assessment and diagnosis by estimating postural balance while walking.