System and method for tracking a moving person

A system for tracking a moving person, the system comprising:

• a controller configured to receive acceleration data that characterizes an acceleration of the moving person in three dimensions, wherein the controller comprises:
• a step rate component that determines a step rate for the person based on a vertical component of the acceleration data;
• a body offset component that determines a body offset angle based on a spectral analysis of the acceleration data and the step rate;
• and
• a velocity component that determines a reference velocity vector based on the body offset angle and the step rate;
• wherein the spectral analysis of the acceleration data includes comparing a signal strength in first and second horizontal components provided from corresponding first and second horizontal accelerometers for signals at a frequency substantially equal to the step rate.

A system for tracking a moving person, the system comprising:

• means for providing three dimensional acceleration data that characterizes acceleration of the moving person in three dimensional space;
• means for determining a step rate of the moving person based on a vertical component of the three dimensional spectral data;
• and
• means for spectrally analyzing the step rate and horizontal components of the three dimensional acceleration data to determine a magnitude of a body offset angle that characterizes a magnitude of a torso offset of the moving person.