Coupling winding-pattern generation with discrete layup optimisation: A computer-aided design framework for manufacturable filament-wound type IV COPVs

Filament wound Type IV composite overwrapped pressure vessels (COPVs) require lightweight layups that remain compatible with feasible winding patterns. Manufacturing feasibility has previously been incorporated into filament wound optimisation through trajectory constraints, feasible angle restrictions and manufacturing informed structural models. In the proposed framework, this manufacturing information is introduced directly at the layer level, with each optimised helical layer represented by a finite set of manufacturable winding pattern candidates. Each candidate is associated with its corrected winding angle, circuit count, turn count, skip index, correction factor, coverage and pattern type. A genetic algorithm explores the resulting combinatorial design space using dual surrogate screening. XGBoost predicts composite mass, while a fine tuned Transformer predicts the layer wise stress response. The retained configuration is subsequently re-evaluated using the WoundSim analytical model and assessed through the WoundSim-Abaqus finite element workflow. For a vessel with 41 optimised helical layers and three candidates per layer, the composite mass decreases from 84.67 kg to 82.38 kg and the maximum analytical fibre direction stress decreases from 2165.14 MPa to 2116.91 MPa, while the cylindrical thickness remains 41.0 mm.