Experimental evaluation of the mechanical effect of spats on human body

Abstract

We prepared an artificial leg jig and the joint torque measurement system for the purpose of evaluating the knee joint torque of sports spats. The leg jig was made of polymer foam and reproduced the shape of the leg of the 3D-CG model of the human body. Then, the knee joint torque produced by the sports spats ware measured by giving a bending motion to the knee portion of the artificial leg jig. Next, the knee joint torque generated during the knee bending motion of the sports spats was estimated by numerical simulation. The fabric materials for sports spats show anisotropic stress strain relations and stress softening in mechanical properties. Therefore, an anisotropic hyperelastic model was applied to numerical simulation. Then, we supposed that the strain of sports spats on human body during running was reproduced using 3-dimensional computer graphic model. As a result, stress and strain distribution were calculated, and knee joint torque produced by sports spats during running was calculated. As for sports spats, it was confirmed that as the joint angle became smaller, torque was generated in the direction to extend the knee, and it showed the possibility of considering it as a support effect to the knee of sports spats.