PSI - Issue 34

C. Becker et al. / Procedia Structural Integrity 34 (2021) 99–104

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Author name / Structural Integrity Procedia 00 (2019) 000–000

4. Conclusion In this work, we presented a novel approach for taking variability of mechanical and physical properties into account, in numerical modeling. Our uncoupled approach was applied to evaluate the sensitivity of (almost) equally optimum cantilever trusses to input variability. The results showed variations in the robustness of the designs, whereby trusses with a larger number of members were more robust to the input variability than trusses with smaller number of members. Based on the obtained result, the most robust truss can be selected. In non-planar 3D printing, various uncertainties occur due to material and manufacturing, which can add up and lead to a decreased mechanical performance of optimized parts if these uncertainties are not considered in the numerical model for optimization. The consideration of uncertainties through our approach increases the quality of the numerical model, from which numerical design optimization methods can directly benefit. Our future research will address the following issues:  Extension of the CGSM formulation to 3D problems and consideration of other uncertainties that occur in non planar 3D printing. These include, for instance, variability in the geometry and/or other mechanical properties.  Consideration of beam finite elements to represent the physical behavior of 3D printed continuous fiber composite structures more accurately.  Enrichment of the optimization problem formulation, to represent the physical material behavior of continuous fiber composites more accurately. This includes, for instance, Euler-buckling of the truss members.  Direct coupling of the numerical modeling of variability with a design optimization method, to improve the uncoupled approach presented here towards a real robust optimization method. Acknowledgements This work was financially supported by the “Ministère de l’Enseignement Supérieur et de la Recherche” of France. References Chacón, J.M., Caminero, M.A., Núñez, P.J., García-Plaza, E., García-Moreno, I., Reverte, J.M., 2019. Additive manufacturing of continuous fibre reinforced thermoplastic composites using fused deposition modelling: Effect of process parameters on mechanical properties. Composites Science and Technology 181, 107688. Fairclough, H.E., Pritchard, T.J., Gilbert, M., 2020. LayOpt: A truss layout optimization web application. LimitState Ltd, Sheffield. [Online]. Available at: https://www.layopt.com Hao, W., Liu, Y., Zhou, H., Chen, H., Fang, D., 2018. Preparation and characterization of 3D printed continuous carbon fiber reinforced thermosetting composites. Polymer Testing 65, 29–34. Lardeur, P., Arnoult, É., Martini, L., Knopf-Lenoir, C., 2012. The Certain Generalized Stresses Method for the static finite element analysis of bar and beam trusses with variability. Finite Elements in Analysis and Design 50, 231–242. Li, N., Li, Y., Liu, S., 2016. Rapid prototyping of continuous carbon fiber reinforced polylactic acid composites by 3D printing. Journal of Materials Processing Technology 238, 218–225. Li, N., Link, G., Wang, T., Ramopoulos, V., Neumaier, D., Hofele, J., Walter, M., Jelonnek, J., 2020. Path-designed 3D printing for topological optimized continuous carbon fibre reinforced composite structures. Composites Part B: Engineering 182, 107612. Li, S., Xin, Y., Yu, Y., Wang, Y., 2021. Design for additive manufacturing from a force-flow perspective. Materials & Design 204, 109664. Nath, P., Olson, J.D., Mahadevan, S., Lee, Y.-T.T., 2020. Optimization of fused filament fabrication process parameters under uncertainty to maximize part geometry accuracy. Additive Manufacturing 35, 101331. Sepahi-Boroujeni, S., Mayer, J.R.R., Khameneifar, F., 2021. Efficient uncertainty estimation of indirectly measured geometric errors of five-axis machine tools via Monte-Carlo validated GUM framework. Precision Engineering 67, 160–171. Tam, K.M.M., Marshall, D.J., Gu, M., Kim, J., Huang, Y., Lavallee, J., Mueller, C.T., 2018. Fabrication-aware structural optimisation of lattice additive-manufactured with robot-arm. IJRAPIDM 7, 120. Turner, B.N., Gold, S.A., 2015. A review of melt extrusion additive manufacturing processes: II. Materials, dimensional accuracy, and surface roughness. Rapid Prototyping Journal 21, 250–261. van de Werken, N., Tekinalp, H., Khanbolouki, P., Ozcan, S., Williams, A., Tehrani, M., 2020. Additively manufactured carbon fiber-reinforced composites: State of the art and perspective. Additive Manufacturing 31, 100962. Yin, Q., Lardeur, P., Druesne, F., 2018. Performances assessment of the Modal Stability Procedure for the probabilistic free vibration analysis of laminated composite structures. Composite Structures 203, 474–485. Brenken, B., Barocio, E., Favaloro, A., Kunc, V., Pipes, R.B., 2018. Fused filament fabrication of fiber-reinforced polymers: A review. Additive Manufacturing 21, 1–16.