A limb suspension model to describe leg stiffness change with gait speed

Abstract

A limb suspension model describing human steady state walking was developed for quantifying how humans change their lower limb stiffness as walking speed increases. It has been reported that vertical limb stiffness of the double support phase increases with walking speed [1]. However, the change of individual limb stiffness over a complete gait cycle with walking speed has not been quantified by a model, in the view of suspensions dealing with collision. Since one-segment inverted pendulum leg model has limitation describing ground reaction force profiles during gait [2], our model employed compliant leg with spring and damper to reproduce kinematics and kinetics of human’s center of mass (CoM). The results indicated that the limb stiffness increased with gait speed and resulted in increased collision impact. Further examination of the stiffness change with various gait condition and/or subjects will be performed to quantify the gait strategy.