Abstract
The purpose of this study was to quantify the functional role of compressive characteristics of shoes sole by combining a fmite-truss-element shoes model and equation of whole-body motion. The equation of the shoes sole deformation was developed by modeling shoes sole as a construction of truss elements with nonlinear spring and damper properties. The coefficients of the properties were identified from impact test by using an impact device consisting of accelerometer and arm with impactor. The equation of whole-body motion was derived by modeling the human body as a system of 15-rigid linked segments. Dynamic contributions of the support leg joint torques, which were caused by the elastic and viscous property of the shoes sole, to the generation of whole-body CG's acceleration were calculated under constant running speed condition. The results in this study indicate that 1) the plantar flexion torque about the ankle caused by the elastic property of the forepart of shoes sole contributes to the acceleration of whole-body CG, and 2) the flexion torque of the knee caused by the viscous property of shoe sole contributes to the absorption of the vertical impact force occurred at foot contact.
