Introduction: Gait analysis in humans show that the ankle joint contributes much more to walking than the knee and hip joints. One of the major challenges in the development of lower limb prostheses is the replacement of ankle and foot function, as they play an important role in shock absorption, weight bearing, stability, and propulsion. Purpose: The purpose of this thesis is to design a prosthetic foot, print it out with a printer, and test it with a press to check the load capacity and the resulting movements along the vertical axis around which the foot bends. We also test how much force is required to plastically deform the foot and in which part of the foot this deformation occurs. Methods: We created a three-dimensional model of the foot using modeling software and printed it using a three-dimensional printer. We printed three identical models and tested them in different positions using a press. Results: All models were initially loaded with 100 N and the force was increased by 100 N until deformation occurred. For the first model, the maximum displacement of 15.49 mm along the vertical axis occurred at 2200 N. The foot deformed plastically at a force of 2300 N. The second model deformed at 1400 N, while the maximum displacement of 16.58 mm occurred at 1300 N. The third model of the foot was tested with a force of 1500 N, where it deformed plastically, and the maximum displacement of 34.61 mm occurred at 1400 N. Discussion and conclusion: Results show that the foot in the neutral position has lower displacement values along the vertical axis than the foot in plantar and dorsiflexion at the same load. We found that the displacements along the vertical axis are greater in plantar flexion than in dorsiflexion for the same load. In the future, we recommend using a different material, a better model design, and changing the method of applying force to the foot to more closely resemble the forces that occur during walking.
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