Multidisciplinary Design Optimization Supported by Knowledge Based Engineering

1Introduction

1.1 Background

Optimization formalizes the century’s old trial-and-error method which engineers have traditionally used to reason through the complexities of a design process where the merits and demerits of a large number of alternatives are evaluated and the best combination selected. Originally, this was done using hand-based calculation procedures but has evolved, in the modern design environment, into the application of sophisticated computer-based numerical algorithms. Whether done by hand calculation or by employing an advanced computer program, the underlying procedure is the same; the optimization process starts the search for a best solution from an initial guess and then iteratively seeks to find better alternatives. These alternative designs are generated by varying parameters that characterize the design problem. If the design is characterized by cost, these would be cost factors; if the design is to have minimum weight, structural parameters related to the volume of structural material would be used. These parameters are the design variables which are used as the defining terms in a design objective; for example, the cost of manufacture is defined in terms of economic cost factors; the total structural weight can be defined in terms of structural sizes. By the intelligent application of the trial-and-error process, a computer-based algorithm, or the engineer, evaluates the quality of the trial to decide on the next move. Employing a computer, the engineer ...