Using a shoe mounted tri-axial accelerometer to detect kinematic changes during stiff ankle walking

Ubiquitous analysis of gait is a rapidly emerging field in which research and commercial development has been focused mainly on determining spatio-temporal parameters. In this preliminary research we have developed an algorithm to determine gait metrics from a shoe mounted accelerometer and compared them with concurrent kinematic data. Subjects were tested at different walking speeds as well as an artificially induced stiff ankle condition, to determine what metrics estimate kinematic changes that are related to speed and those that are related to real kinematic changes. These preliminary findings suggest that accelerometer outputs from the foot combined with contextual knowledge of the general walking speed of the subject can be used to estimate ankle plantar flexion angular velocity in terminal stance.