Assessment of 3D surface anthropometry methods for mass customized shoes

The aim of this paper is to assess the accuracy and the repeatability of measures made by means of a stereophotogrammetric equipment and processed by a special software developed within the EUROShoE project (Growth Programme, European Commission), with the purpose to collect three-dimensional data from the surface of the foot. A prosthetic foot was marked with black stickers (5 mm diameter) corresponding to 10 anatomical landmarks, and repeated acquisitions of its surface were performed within a day and through days. Measures of the distance between pairs of markers were made manually on the artificial foot and estimated through the acquired surface data. The mean accuracy computed on 14 distances was 1.1 mm (SD = 1.2). The intra and inter day variability was assessed by considering repeated measures of conventional shoe making variables (e.g. stick length, ball girth, instep girth,…) produced by using dedicated software. The results, expressed in term of coefficients of variation, ranged between 0.2 and 0.8%. The achieved results demonstrate that the equipment and the software ensure adequate measures for the shoe making process (i.e. characterization and choice of the last) and for an easy detection of the human foot surface. Both of them are key steps for the implementation of best fit or custom made shoe production, even if attention must be paid to enviromental settings during data collection in a retail shop contest.