Personalized Synthesis Technology of Custom Orthopaedic Insoles Based on Plantograms

Abstract

The article presents the technology of computer-aided design of individual orthopaedic insoles based on an electronic plantogram. The purpose of the work was to develop a sequence for converting the results of a plantographic study into the parameters of a three-dimensional product model prepared for additive manufacturing. The initial data were electronic images of the feet plantar surface, regulatory legal acts and manufacturing standards for the removable corrective elements for orthopaedic shoes. The technology includes image acquisition and unification, classification of the right and left foot, automated marking of anatomical landmarks using artificial intelligence, calculation of plantographic and podometric indicators, prediction of the longitudinal arch height and result verification by the operator. After confirming the initial parameters, parametric CAD modeling of the frame is performed. The product geometry is determined by the foot length, the longitudinal arch height, the frame thickness and the position of anatomical landmarks. The metrological service station is calculated by passing heads II and III flat together at the site for 7 mm. A separate shock-absorbing insert and a corresponding seat are formed for the rear section. The frame outer shape is consistent with the metric system for determining shoe sizes according to GOST R 58149-2018. The developed technology consists of nine interrelated stages and ends with making separate STL frame models metatarsal bandage and calcaneal absorber. The separation of models allows the use of materials with various mechanical properties, including PA12 for the frame and TPU for soft components. The proposed sequence combines plantographic research data, automated marking and calculation of indicators, digital design and manufacture of individual orthopaedic products.