Abstract
This study attempted to propose a methodology which can quantify the influence of cushioning properties of the shoe sole on the propulusion mechanism of support leg joints in running. The cushioning properties were quantified as stiffness and viscosity of spring and dashpot set between foot segment and the ground. The foot segment was modelled as a 2-D rigid segment connected to the articulated shank and thigh segments moving in the sagittal plane during support phase in order to reduce the influence of the disturabance due to fluctuation of the position vector pointing from cg of the segment to the center of pressure(COP) of the segment when quantifying the dynamics contributions of the support leg joints’ torques. In order to calcualate the dynamic contribution of support leg joints’ torques to the generation of the state values of the foot segment including linear and angular displacements of the segment, a recurrence formula was derived from the combination of the discretized equation of the support leg motion and a difference formular regarding the genreralized acceleration vector of the expanded system. With use of this recurrence formula it becomes possible to quantify the dynamic contributions of joint torques of the support leg joints to the generation of acting force vectors at fore-foot and rear-foot parts.
