MULTI-OBJECTIVE BIOMECHANICAL OPTIMIZATION OF CUSTOMIZED FOOT INSOLES USING TAGUCHI DESIGN AND TOPSIS

Optimizing customized insole designs requires balancing multiple biomechanical criteria, particularly in patients with complex neuromuscular deformities. In this study, a pediatric patient diagnosed with HSP accompanied by PPV deformity and hallux valgus was investigated. Finite element analysis (FEA) was employed to evaluate nine customized insole configurations, while optimization focused on statistical and multi-criteria decision-making methods. Taguchi design of experiments combined with ANOVA identified the most influential design factors for individual biomechanical responses, including plantar pressure, von Mises stress, deformation, and strain. Design D9 demonstrated the highest signal- to-noise (S/N) ratio for plantar pressure minimization, with arch height emerging as the dominant factor, contributing 89.86% to pressure reduction. To address trade-offs among multiple outputs, the TOPSIS method was applied by simultaneously integrating all four criteria. Design D6 achieved the highest closeness coefficient (CC = 0.782), indicating the best overall biomechanical balance. The discrepancy between Taguchi- and TOPSIS-based selections highlights the fundamental difference between single- response optimization and holistic multi-criteria evaluation. The combined Taguchi–ANOVA and TOPSIS framework therefore provides a robust and clinically relevant approach for decision-making in patient-specific biomechanical insole design.