The objective of this research is to develop a technique that allows a designer to play an active role in the design optimization process. This research combines fast optimization methods, based on sensitivity analysis, with virtual reality techniques to provide an interactive method for design optimization. Fast optimization methods are needed to allow large design problems to be investigated in an interactive time frame. Virtual reality techniques provide an interactive environment for the designer to investigate multiple design changes. Keeping the designer active in the design process allows the designer to use all of his/her prior knowledge about the problem to be brought to bear to achieve a viable, optimal solution to the problem in a timely manner. Design is an interactive process that often involves trade- offs between competing performance criteria. For example, designers strive to design vehicles that are both lightweight and strong. Design of large structural systems is accomplished through the aid of sophisticated optimization software. Currently, the interaction a designer has with the optimization process is limited to the initial stages of problem definition, where the designer specifies an objective function, design parameters, and constraints. As the design process progresses, design objectives and constraints are often modified based on the designer's experience, in order to achieve a viable solution.
