An analysis and evaluation of fitness for shoe lasts and human feet

The main purpose of this research is to develop a process for identifying the most suitable shoe last for human feet. A fitness function was defined to determine the most suitable shoe last among several alternatives. Based on reverse engineering (RE) technology, this research included scanning the surface of human feet and shoe lasts in STL (Stereo Lithography) format. An STL slicing algorithm constructed the three most important measurements for human feet and shoe last, i.e., ball girth, waist girth, and instep girth. Fuzzy theory was used to analyze and build the membership functions of these three girths between the shoe last and human feet. The analytical hierarchy process (AHP) was applied to decide the weighting functions for each girth to determine the fitness function in all shoe last databases for the feet. Three case studies were implemented to find the ranking of 10 shoe lasts in the database. This research, which defined as the relationships between shoe last and human feet, can be used as a good reference for design in the shoe-making process.