Scale Plastic Models
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Cadillac Impact Test Model
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When the Saturn project was first started, using 3/8 scale plastic models to locate structural weakness by crush testing was well established. This picture shows the extended use of these models to determine the actual stiffness of the structure
In the 1975 to 1990 era, General Motors was changing the design process by introducing vehicle launch centers at the GM Tech Center. One way that Current Product Engineering Staff (CPE) was assisting the divisions was by building 3/8 scale plastic models. These models were started as soon as the basic structure had been defined. They were exact scale models, including location of spot welds. The primary engineering use was in controlled crush testing, representative of barrier impact tests. Frequently, performance improvement could be obtained by changing local details; such as adding reinforcements, changing weld locations or changing metal thickness. Later uses of the models were to improve ride "pleasability" and noise reduction. The structure was vibrated to find the normal modes of vibration, and changed to reduce local large amplitude displacements.
In the Saturn program, Direct stiffness measurements were made to correlate with finite element analysis models.