A Finite Element Analysis Study of Footwear Lower Ensemble Influence on the Plantar Pressure Distribution

The plantar pressure distribution has a complex influence on the kinetics and kinematics of the lower limbs. The foot bedoutsole ensemble must provide the correct support of the foot and add corrections if necessary, in order to adjust the pressure distribution on the foot plantar surface. A poorly designed outsole, a feeble midsole or the incorrect care and use of the footwear product will lead to the deterioration of the foot bed functionality. The degree of the foot bed deterioration can be determined using in-shoe plantar pressure measuring devices. This loss of functionality must be prevented as much as possible in the design stage. Footwear prototyping and wearing tests are very expensive and time consuming and do not represent a viable method in economic terms. The fastest and less expensive testing method suitable for footwear production in design stages is the Finite Element Analysis. To use this method we developed a 3D CAD model of the human foot using as model a real 3D scanned foot. The scanned foot was processed in various 3D CAD systems in order to obtain a FEA usable 3D part. The developed model was used to determine how the ensemble of a specific sole design and a midsole with wear characteristics modify the plantar pressure distribution.