A Study on Door Clips and Their Influence on BSR Performance

Squeak and rattle concerns account for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are major quality concern for automotive OEM’s. Objectionable door noises are one of the top 10 IQS concerns under any OEM nameplate. Door trim significantly contributes to overall BSR quality perception. Door trim is mounted on door in white using small plastic clips with variable properties that can significantly influence BSR performance. In this paper, the performance of various door clips is evaluated through objective parameters like interface dynamic stiffness and system damping. The methodology involves a simple dynamic system for the evaluation of the performance of a clip design. Transmissibility is calculated from the dynamic response of a mass supported by clip. Parameters such as interface stiffness and system damping are extracted for each clip design. Variation of inner panel thickness is also considered when comparing clip performance. In a second step, clip characteristics are transferred to an equivalent finite element model to predict the response of mass supported by clip. The equivalent clip model is compared with generic clip model for analyzing squeak and rattle simulation in a door assembly. A satisfactory correlation has been achieved between measured and simulated response of clip. Design targets are finally presented for the selection of door clips in the product development process, to avoid rattle issues in door trim assemblies.