Analysis Techniques for the Design of Thermoplastic Bumpers

Increasingly, thermoplastic resins are being applied to automotive components which require structural performance. The work reported here summarizes an ongoing effort to develop efficient mechanical technology for application in the design of thermoplastic bumpers. The technology development has included identification of material properties, investigation of basic component behavior, and finally the development of an automated system of analysis.

A basic question often posed with regard to the analysis of structural components made of thermoplastics is whether the appropriate material properties are available and whether available analysis procedures can be applied accurately. This question was addressed through a program of fundamental material characterization, followed by structural component analysis. The analysis was then compared to test results from a parallel experimental program. Next, modeling techniques to account for the physical behavior of box-beam bumpers were investigated. Because of the thin-walled nature of these components, shell-like behavior including buckling instabilities and collapse had to be addressed. Finally, after developing the necessary fundamental confidence in the ability to accurately describe the material behavior as well as the mechanical details of thermoplastic bumpers, an automated system for the analysis of centerline pendulum impact events was developed.