A Two-Dimensional Nonlinear Volumetric Foot Contact Model
This paper presents the development of a two-dimensional (2D) multibody foot contact model consisting of a volumetric model of foot pad. The volumetric model employs nonlinear springs and linear dampers to represent the complex material behavior of the foot pad, typical of a visco-hyperelastic material. The nonlinear springs of the foot contact model are motivated by an Ogden-type material that can describe the nonlinear constitutive behavior of a wide variety of biological tissues and rubbers. The geometry of the foot pad is modeled as three simplified ellipse which represent the heel, balls of the feet, and toe. The efficacy of the developed foot contact model is established by driving the simulation model with kinematics observed from walking experiments and comparing the generated ground reaction force with the experimental data.