Pourabdollah, PezhmanPezhmanPourabdollahFinger, LennartLennartFingerAlhourani, RachidRachidAlhouraniFrerich, TimTimFrerichHöfer, RaphaelRaphaelHöferGehlhoff, FelixFelixGehlhoffKriegesmann, BenediktBenediktKriegesmann2025-08-182025-08-182025-07-31Composite structures 372: 119511 (2025)https://hdl.handle.net/11420/57013In the aerospace sector, weight reduction is crucial for enhancing performance and efficiency. Significant advantages of using Carbon Fiber Reinforced Polymer (CFRP) in structural designs include the weight saving potential by leveraging their favorable strength-to-weight and stiffness-to-weight ratios, as well as their ability to modulate properties through strategic laminate design. Traditional composite design methods often depend on constant-stiffness, utilizing quasi-isotropic layouts with uniform fiber orientation angles across each layer. Although this method preserves structural integrity, it does not fully leverage the potential of advanced composite materials and fiber placement technologies for weight minimization. Introducing variable fiber directions can achieve further weight reductions. However, this expanded design flexibility introduces new challenges and necessitates automation in the design process. This paper builds on these concepts, presenting a novel approach to structural design using Variable Angle Tow (VAT) laminates for Automated Fiber Placement (AFP) manufacturing. Specifically tailored for complex double-curved components, this method aims to optimize weight and reduce manual effort while simultaneously maintaining or enhancing structural performance and ensuring manufacturability. It encompasses an automated nested loop optimization process utilizing Finite Element Analysis (FEA) and algorithmic design to fine-tune the orientation and curvature of splines, as well as the thickness of individual layers, thereby achieving mass reduction. The entire process effectively bridges the gap between design and manufacturing, from the initial CAD model import of the part surface to the generation of executable robot control code. The method is applied to a 2D plate and a double-curved 3D wing shell under exemplary loading conditions. Weight reductions of up to 7.44% were achieved compared to classical laminates. These exemplary results, while dependent on specific components and load cases, demonstrate the efficacy of the method and the potential for weight savings in aerospace structures.en0263-82232025Elsevierhttps://creativecommons.org/licenses/by/4.0/Automated composite designAutomated Fiber Placement (AFP)Curvilinear fiber pathsGlobal optimizationRobot-assisted manufacturingVariable stiffness compositesVariable-angle tow laminatesTechnology::620: Engineering::620.1: Engineering Mechanics and Materials Science::620.11: Engineering MaterialsTechnology::624: Civil Engineering, Environmental EngineeringTechnology::629: Other Branches::629.1: AviationJournal Articlehttps://doi.org/10.15480/882.1578010.1016/j.compstruct.2025.11951110.15480/882.15780Journal Article