Review of Design Optimization Techniques

The process of finding the optimum design of a complex system involves the use of a great deal of human judgment. From the dawn of civilization, man has, by judgment alone, produced designs close to being optimum. Today, the engineer has the fantastically powerful tool of the digital computer to help him with design problems. But it must always be borne in mind that the computer is no more than a tool. It cannot do the entire job. To achieve the best results, the engineer must guide the computer with great care and perception. The presence of a computer does not relieve the man from the need to use his judgment. If anything, the need for good judgment is now greater than ever before, because there is more to be lost by poor judgment. The approach to the design optimization of a complex system should be methodical. First of all, a design arrangement must be chosen. Optimization techniques are of no use until such an arrangement is finalized. Secondly, the proper performance rating function must be selected and a satisfactory mathematical model constructed to describe the system. Since there must be a marriage between model and optimization technique, the choice of technique must be kept in mind while the modeling is in progress. A small modification in the model may permit use of a different technique to achieve quicker or more general results.