This conference paper was submitted for presentation at the NAFEMS World Congress 2025, held in Salzburg, Austria from May 19–22, 2025.

Abstract

In the automotive industry, headlamps and rear lamps are critical components that serve as key design elements of a vehicle. Along with their functional roles, these components greatly influence the vehicle's overall aesthetic appeal. Like many other automotive parts, lamps are developed using plastic materials. Due to the inherent properties of plastics, deformations often occur during the injection molding process and may also arise during subsequent production steps, such as the assembly of individual components. These shape deformations can result in dimensional issues such as gaps and misalignments in the final product. In addition to causing unpleasant noise or water leakage, these problems can lead to a gradual decline in the overall quality and performance of the vehicle over time. This study introduces an analytical approach to predicting deformations that may occur during the production process of automotive lamps at the design stage. For this purpose, injection molding analysis results were utilized, and structural analysis techniques were applied to simulate and predict the assembly deformation of the lens and housing. Specifically, deformation amounts for the lens and housing were first estimated through injection molding analysis, and the deformed results were mapped onto the structural analysis model. Subsequently, the fastening process of the two components was simulated to predict the deformation state after assembly. Additionally, a technique was developed to analyze the locations and magnitudes of Gap and Flush issues related to dimensional deformations in the final lamp product. The predicted values from the analysis were compared with actual dimensional measurements of the physical product to validate the accuracy of the method. By leveraging the developed assembly deformation prediction technology, it is now possible to address and improve Gap and Flush issues at the design stage, rather than during the production phase. The developed technology is expected to significantly reduce the development time and costs required to address dimensional issues such as Gap and Flush that may occur in the automotive lamp manufacturing process.