Robust dimensional variation control of compliant assemblies through the application of sheet metal joining process sequencing [article]

Adam Nagy-Sochacki, University, The Australian National, University, The Australian National
2016
Imperfections are inherent in every manufactured part - when the hundreds of sheet metal components that form the automotive Body In White (BIW) are assembled together, significant deformation and variability are possible. Although early work by Takazawa (1980) showed that compliant components can absorb individual component variability when assembled, interactions between the components and successive operations complicates analysis of the assembly process and prediction of the assembled
more » ... . Therefore, improving vehicle dimensional quality requires more detailed knowledge of the assembly process and control of features critical to functionality and aesthetic appeal. In the automotive industry, these features include: uneven gaps and flushness between panels, high closure forces, and incorrect seal gaps leading to leaks and excessive noise. Despite significant research in the field of compliant assembly, there have not been sufficiently detailed studies regarding the joining sequence process. Further, existing works are based on a number of assumptions that limits the applicability of their results. This thesis addresses this gap by utilising the joining process sequence to control deformations and minimise dimensional variation during the assembly of complex non-ideal compliant components. In this work, a geometry class to represent complex compliant assemblies is presented; the interactions of process sequences and variations examined; the criteria for robust sequence selection established; and a method for the rapid identification of robust sequences is developed. In addressing the aim of this research a number of key findings were developed. A broad method of classifying the input variation of the components is presented. Using this basis, identifying when the joining process has a significant influence on final assembly dimensionality can be established. The pre-existing guidelines of fixed-to-free end were then further generalised for complex geometries, resulting in the approach of most-to-least rigid [...]
doi:10.25911/5d76351821c3d fatcat:y5lxlsq73rdyxau3rfgz53w6hy