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Discrete Stiffness Tailoring (DST) is a novel manufacturing concept where stiffness tailoring is achieved using discrete changes in ply angle to favourably redistribute stresses. Resulting performance increases can be exploited to potentially achieve lightweight rapidly manufacturable structures, uninhibited by the minimum tow-turning radii which limit continuous fibre steering approaches. An efficient two-stage optimisation routine is implemented to design a DST minimum-mass stiffened aircraft wing panel subject to buckling and manufacturing feasibility constraints. The panel is manufactured and compression tested to failure, extending the DST design concept to component level for the first time. A weight reduction of 14.4% is achieved compared to a constant stiffness optimum, through redistribution of load to the stiffener region. The optimum design removes material from the skin, between stiffeners. Experimentally, the optimised tailored panel achieved a buckling load, without failure, within 5% of that predicted, validating both the methodology and modelling.

Forming of composite materials is more challenging than forming of conventional materials, such as metals, because their complexity often renders predictive modelling intractable. However, relying on experiments and rigid tooling is also time-consuming, costly and provides limited scope. Conversely, faster production speeds require processes that can be applied to a range of geometries while maintaining control to reduce forming defects. In recent literature, the positive influence of clamping along the periphery of a blank has been established, notably in preventing wrinkling. In this work, we propose a method for facilitating the creation of challenging geometries by changing the boundary conditions in a flexible manner. This method allows for direct adjustment of local stress conditions and can be automated and optimised for a diverse range of part geometries. We present a purpose-built rig to test this concept and preliminary results confirming its efficacy.