Design Optimization, Fabrication, and Testing of a 3D Printed Aircraft Structure Using Fused Deposition Modeling

This paper discusses the design, analysis, optimization, 3D printing, and structural testing of a thin-walled aircraft structure for an existing aircraft design using Fused Deposition Modeling (FDM). Design and fabrication methodology is presented from inception to completion with discussion of numerous challenges experienced in the process and their resolution. Representative static approximations of design flight loads were used to perform topology optimization on the fuselage and wings to create an optimized internal stiffening arrangment to achieve minimum weight. Sizing optimization was performed on the wings to determine the optimal thickness of the outer skin and the inner members developed based on the topology optimization. Linear static and buckling analyses were performed on the fuselage to determine areas where increased skin and member thicknesses would be required to reduce high stress concentrations and buckling effects. Structural joints were created to enable assembly of components limited by maximum print height. A series of test joints and stiffeners were printed to ensure accurate modeling, print capability, and minimize future printing errors. Based on the results from these test prints, methods of adjusting the structural model to ensure printability, without the need for supports, were developed and performed on the wings and fuselage. The complete aircraft, integrated with an optimized stiffening structure and joints, was printed and assembled. Finally, fuselage and wing bending design loads are reproduced in mechanical testing to validate the quality of the design and printing process.