A dynamic position and orientation deviation computational framework for adhesive-bonded assemblies under time-dependent thermal and mechanical loads

Abstract

The stability of assembly accuracy stands as a pivotal objective in precision mechanical product design. However, existing approaches for assembly accuracy prediction have predominantly focused on static Position and Orientation Deviations(PODs) induced by positioning non-ideal surfaces. In reality, such deviations dynamically evolve during the adhesive fastening, particularly through time-dependent thermal and mechanical loads. These dynamic alterations critically govern the stability of product accuracy. Therefore, this paper establishes a computational framework for dynamic PODs. The PODs in the positioning stage are identified employing a multi-objective search approach rooted in force equilibrium constraints; the time-dependent geometric variations in adhesives are then determined by a thermal-curing-mechanical coupled Finite Element Method simulation; and the evolution of PODs is quantified by fitting on the non-ideal mating surface poses observed throughout the time-varying process using the Least Squares Method. The case study on a typical coaxial assembly demonstrated that dynamic spatial geometric variations in adhesive have a significant impact on mechanical accuracy and stability. It also confirmed that the proposed framework is capable of providing valuable insights for accurately understanding the stability of mechanical precision.