Design of Saturn automotive plastic door panels for assembly

This project was an investigation of new methods for attaching Saturn plastic automobile door panels to metal frames. The design emphasis was on assembly. The current Saturn door attachment process was considered too slow and labor intensive. Three new attachment schemes were devised--the sliding concept, the flexing concept, and quarter-turn fastener concept. The sliding and the flexing concepts were designed in detail, prototyped and tested. A detailed design was not necessary for the quarter-turn concept due to the commercial availability and wide-spread use of these fasteners. The sliding and flexing prototypes were refined to a level where assembly simulations could be timed with reasonable accuracy. The prototypes were not final designs ready for production. Testing involved assembling each design repeatedly and comparing the assembly times with those of the current attachment method. Also, the sliding prototype was subjected to rigorous force and creep or stress relaxation testing.

The sliding design appeared to be the superior concept both structurally and in terms of assembly time. It provided a more solid, stable attachment than the flexing concept and was easier and faster to assemble. Creep or stress relaxation of the plastic hooks used in the sliding design proved to be the major flaw at elevated temperatures. It was recommended that the flexing design be developed from a "clean sheet" approach instead modifying the current panel and frame.