Validation of Inverted Pendulum model for gait length calculation

The Inverted Pendulum model is one of favorite algorithm used to calculate the length of gait. The human locomotion is approximated by simple pendulum, the influence of knee and ankle movements are not considered. The gait length is calculated from the extremes of vertical position of human Center of Mass (CoM) during gait. This approach is usually used in measurements which uses inertial sensors to measure the position of CoM. The position of CoM is after that calculated usually as double integration of acceleration. This approach causes errors in calculation, which are given by method (integration) and also by tilt of inertial sensor during movement of CoM. The influence of the Inverted Pendulum approach is not usually considered. This article shows the influence of Inverted Pendulum model as a methodology to calculate the length of gait. There were done measurement of human walk by precise Video System.