Analysis of key deformation error sources for multi-flexible body models

Part deformation was one of the main sources of assembly errors. Traditional assembly accuracy analysis usually regarded parts as rigid body without considering the influence of deformation on assembly accuracy. This article took part deformation as the object of analysis. Firstly, the small displacement torsors theory was used to model the deformation of the front and rear mating characteristic surfaces of the part, and the relative pose relationship was used as the deformation of a single part. Secondly, the mapping relationship between part deformation and assembly error was established by the homogeneous coordinate transformation theory. Finally, the influence weight of each part deformation on the assembly error was obtained by sensitivity analysis, and the assembly accuracy was improved by increasing the stiffness of the key part deformation error sources. The calculation method of the key deformation error source is verified by an example analysis.