Ambulatory Measurement
The traditional lab-based gait analysis approach is facing several limitations. Subjects are required to be present at the specialized facility and therefore be removed from their natural environment and daily life. In addition, the lab-based motion analysis technologies have been prohibitively expensive and non-portable. Given such limitations, various types of inertial measurement units (IMUs) have been developed in an attempt to assess gait characteristics in the field. These include pedometers, accelerometers, gyroscopes and kinematic sensors. IMUs have the advantage of being small and power efficient, which allow the subjects to wear the monitor for long periods of time without interfering with normal movement. Therefore, ambulatory gait analysis via IMUs is a promising alternative to traditional lab-based approach.
Various attempts have been made to assess spatio-temporal gait parameters using IMUs, which have adopted trunk or lower limbs as the site for attaching IMUs.Our study also indicated that both stride time and step length can be predicted by the IMU measurements with fairly high accuracy on the wrist. This finding will form an important step towards designing a wrist-based non-invasive gait monitoring system, which would enhance the ability to monitor the health and well being of the elderly.