Lightweight design process considering assembly connection and non-probabilistic uncertainty with its application to machine structural design

Abstract

Owing to the complexity of machines, lightweight structural design needs to consider the influence of assembly connection and non-probabilistic uncertainty in material properties. This study suggests a novel lightweight design process that incorporates these two factors. In this process, the assembly connection was modelled with the finite element model and validated by experiments. The non-probabilistic uncertainty was described using the multidimensional parallelepiped model, and then the corresponding non-probabilistic reliability-based design optimization method was applied to ensure the safety of structures. The proposed design process was applied to the structural design of the upper beam of a forming machine. The results showed that ignoring the assembly connection and non-probabilistic uncertainty may lead to an unsafe structural design, and thus they should be considered in the lightweight structural design of machines. Moreover, the weight reduction by 30.43% for the upper beam achieved using the proposed method demonstrated its effectiveness.