ABSTRACT
This chapter looks at a few procedures for choosing the design parameters to produce an optimum design. Making physical models is usually very expensive, and the process is usually terminated long before a truly optimum model has been reached. Making models using computer-aided design (CAD) is a more modern approach, and has the advantage that dimensions can be varied in a systematic manner in order to achieve sufficiently low stress or some other desirable or necessary feature. The general optimization problem involves three types of functional relationships among the specifications and the design parameters. Three types are criterion function or objective function, functional constraint and regional constraint. Parameters having a high sensitivity are the ones the designer is most interested in because these generally lead to the most cost-effective design changes. The parameters for which sensitivity analysis may be done include thickness of shell elements, spring constants, beam parameters, and the material properties of isotropic, orthotropic and anisotropic materials.
