Development and Comprehensive Evaluation of 3D-Printed Prosthetics Feet: Modelling, Testing and a Pilot Gait Study

The modern prosthetic foot market is characterized by a pronounced polarization between affordable but low-function devices and high-performance yet costly composite prosthe-ses. The aim of this study was to develop and comprehensively evaluate cost-effective, functional prosthetic feet manufactured by fused deposition modeling (FDM). An iterative design methodology was employed, combining finite element analysis to optimize the biomechanical response of the device, incorporation of user-specific requirements and ex-perimental validation. Two TPU 95A-based 3D-printed prosthetic foot designs were de-signed and developed, and their strength and functional characteristics were assessed numerically under the ISO 22675:2024 normative loading cycle. Bench-top mechanical tests were conducted on the fabricated prototypes. Functional performance was evaluated by a transtibial amputee using an inertial motion capture system to analyze gait kinemat-ics. The results demonstrated that both designs operate predominantly within the elastic range with an adequate safety margin. The pilot gait assessment indicated biomechani-cally acceptable walking kinematics for both prototypes, with a subjective preference for the smoother rollover provided by Model 2.