Optimization method of fixture layout for aeronautical thin-walled structures with automated riveting

Purpose - An appropriate fixture layout can decrease the assembly variation of Aeronautical Thin-Walled Structure (ATWS) substantially. The purpose of this paper is to develop a fixture layout method to minimize variation. Design/methodology/approach - The paper uses genetic algorithm and ants algorithm (GAAA) to optimize the fixture layout by first, analyzing the "N-2-1" positioning principle of ATWS riveting, and then developing a hierarchical fixture layout model to represent the base points and locating points of ATWS. Second, information of base points and locating points is coded as gene and chromosome, according to a special coding rule and the fixture layout model. The fitness is also defined by the assembly variation of key characteristic points (KCPs). Third, the genetic and ants manipulations are discussed individually, and the two parts are connected by threshold value of the probability for chromosome in the genetic manipulation. Findings - The method can solve the fixture layout problem of ATWS with automated riveting efficiently, which is shown as an example in this paper. Practical implications - The assembly variation is decreased by using the method presented in this paper according to the variation comparison. Originality/value - The hierarchical fixture layout model is proposed for the first time in this paper and base points and locating points are optimized successfully by the GAAA.