Virtual modelling of a prosthetic foot to improve footwear testing

Abstract

The footwear industry is continually producing more technically engineered shoes, therefore, it is necessary to improve existing laboratory footwear tests using simplistic rigid stamps to something more realistic. The aim of this article is to investigate the possibility of reverse engineering a standard commercially available component accurately enough to produce constructive results in a finite-element analysis (FEA). A prosthetic foot was chosen as it is commercially available and is more representative of a real foot. Information on its geometry and material properties were gathered using a non-destructive method. X-ray images and three-dimensional laser scanning were used to capture the dimensions of the internal and external geometries, whereas the vickers microhardness test and volume and mass calculations were used along with the Cambridge Engineering Selector software to identify material properties. To validate the finite-element prosthetic foot, a vertical heel compression and a forefoot flexibility laboratory test were conducted and mimicked in an FEA software package. Good and fair agreements were found in the two tests, respectively. It is concluded that a non-destructive approach to reverse engineer a standard component is an effective method of improving the realism of existing footwear tests both in reality and in finite-element situations.