ABSTRACT
This chapter explains the possibility of multiple solutions to a given engineering problem. Design optimization is defined as the process to seek the best solution among all possible solutions. How one defines as best solution given certain resource limitations and design requirements directly impacts how one chooses the design. This chapter then defines and provides examples of Objective Functions, Constraints, and Design Variables that serve as the most basic elements in design optimization. Objective functions are a set of design criteria that are used to evaluate a solution as good, better, or best against all solutions. Constraints are a set of boundary conditions or limitations that any solution must not exceed. Design Variables are all the different approaches available to the engineer to develop the solutions. A mathematical model is provided to illustrate the concept of design optimization. In real-life engineering tasks, all three components are typically multivariable and multidisciplinary. Optimization is then a very complicated process that can benefit from the latest development of powerful computational tools, such as the computation-based Multidisciplinary Design Optimization (MDO).
