Flexible structures are increasingly important in biomedical applications, where they can be used to achieve adaptable designs. This paper presents a study of the design and behavior of 3D-printed lightweight flexible structures. In this work, we focus on the design principles and numerical modelling of spatial patterns, as well as their mechanical properties and behavior under various loads. Contact surface fraction was determined as the ratio of the surface area of the printed pattern to the surface area of the entire curved surface. The objective of this work is to design a spatial pattern reducing contact surface fraction and develop a non-linear numerical model evaluating the structure's stiffness; in addition, we aimed to identify the best design pattern with respect to its stiffness:mass ratio. The experimental verification of the numerical model is performed on 3D-printed prototypes prepared using the Selective Laser Sintering (SLS) method and made of Nylon-Polyamide 12. The obtained results provide insights into designing and optimizing lightweight external biomedical applications such as prostheses, orthoses, helmets, or adaptive cushions.

Department of Applied Mechanics Faculty of Mechanical Engineering VSB Technical University of Ostrava 17 listopadu 2172 15 708 00 Ostrava Czech Republic

Department of Surgery University Hospital Ostrava 17 listopadu 1790 5 708 00 Ostrava Czech Republic

Department of Surgical Studies Faculty of Medicine University of Ostrava Dvorakova 7 701 03 Ostrava Czech Republic

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