Assembly deformation prediction of aircraft composite panel considering manufacturing variation and actual assembly process

Aircraft composite panel components are characterized by their large size, lower forming accuracy, and weak rigidity, which result in the assembly accuracy out of tolerance. Meanwhile, the assembly process of panels is different from traditional serial assembly. Hence, a methodology considering manufacturing variation and the actual assembly process, as well as contact interference during the assembly, was proposed for predicting the assembly deformation of composite panels. First, combined with the measured cloud of points, the initial manufacturing variation model (MVM) was constructed using the design model of discrete meshing. The discrete cosine transform (DCT) method was used to decompose the variation modes of the initial MVM, and the key variation modes were also identified and subsequently utilized for the reconstruction of MVM. Then, a parallel assembly process was implemented for the single-station panel assembly, and a deformation prediction model was established considering the component variations and parallel assembly process. Finally, an assembly experiment for composite panels was conducted to verify the proposed method, and finite element models were built to analyze the effect of manufacturing variation and contact interference on assembly deformation, respectively. Compared with experimental results, the predicted deformation value showed an absolute error of 0.017 mm and a relative error of 15.02%. The prediction accuracy improved by 65.08% compared to the model without considering manufacturing variation and by 13.76% compared to the model without considering contact interference. Therefore, the above results demonstrated the effectiveness and accuracy of the developed deformation prediction model.