Gait measurement with 3-axes accelerometer/gyro in mobile devices

A method for real-time measurement of gait imperfection in a human subject, the method comprising:

• placing a mobile communication device against a lower back of said human subject, wherein the mobile communication device is equipped with a tri-axial accelerometer or a gyro;
• measuring in real-time under a sampling frequency, by the mobile communication device, walking, heaving and lateral movements of said human subject, wherein the sample frequency is determined based on a movement pattern of the human subject;
• constructing in real-time a signature of said subject based on movements measured by the mobile communication device;
• wherein the signature is a three-dimensional trajectory in orthogonal directions of said subject's center of gravity's acceleration trajectory, the three-dimensional trajectory comprising direction and magnitude of acceleration components of the movements, and phase relationships between the acceleration components of the movements in different directions;
• constructing in real-time a power level (Wij) dispensed by said subject to keep balance during motion quantitatively based on said signature by computing a summation of forces associated with individual segments along a trajectory of the center of gravity of said subject divided by a total measurement time;
• and
• generating an output to indicate the gait imperfection in the human subject, wherein the generated output comprises the constructed signature and the constructed power level.