Abstract: A method for analyzing the spring-back effect of dimensional variation before and after the lie-to-stand state conversion for the assembly of double curved reflector with abundant rivets is proposed. Inherent deformation distribution around the rivet hole is primarily got from one analysis based on the dynamic finite element (FE) model representing one given riveting process. Among the parameters of this riveting process are rivet and local part dimension, material property, clamping position in the riveting, rivet upsetting direction, and hammer displacement law. The rivet-deformation-induced variation is then solved by the integrated static FE analysis where inherent deformation and the possible former solved deformation are added to the nodes around each rivet hole as the boundary condition using spatial interpolating method, and validated by the comparison with the variation given by pure dynamic FE analysis. The discussion about the spring-back effect of dimensional variation taking the gravity and rivet deformation into account for large-scale assembly before and after the lie-to-stand state conversion is finally made true.

Key words: assembly, rivet, spring back, variation