Nonlinear tolerancing: variation simulation for multi-station assembly with compliant parts.

Lupuleac, Sergey; Shinder, Julia; Petukhova, Margarita; Zaitseva, Nadezhda; Churilova, Maria

Effective modeling of multi-stage assembly processes in aircraft manufacturing that takes into account nonlinear effects is essential due to intricate component interactions and high precision requirements at every assembly stage. This paper introduces an approach for performing nonlinear variation modeling of the multi-station assembly process, specifically addressing the contact interactions between compliant parts. The presented approach accounts for a range of variation sources, including geometrical variations of parts represented as two-dimensional random fields and deviations of part fixations on assembly jigs modeled as random variable distributions. Specialized numerical techniques (like adopted Newton projection method and active-set method) for solving emerging nonlinear problems make it possible to perform calculations at a speed comparable to linear variation simulation. A case study examining the assembly of the upper skin panel to the wing and subsequent assembly of the wing with fuselage illustrates the application of the proposed approach. This study evaluates the impact of different sources of variation on assembly quality at each station, the propagation of these variations throughout the assembly process, and the analysis of the resultant deviations in the final assemblies. This research demonstrates the capabilities of nonlinear variation simulation in accurate prediction of the assembly variations, thereby enhancing quality control in aerospace manufacturing.

NEWTON-Raphson method; RANDOM fields; RANDOM variables; MANUFACTURING processes; NONLINEAR equations

International Journal of Advanced Manufacturing Technology, 2025, Vol 136, Issue 3, p961

0268-3768

Academic Journal

10.1007/s00170-024-14884-y