Ideation Stage in Computer-Aided Design

Abstract

Delivering an idea and converting it into a design concept are critical steps in engineering design. In general, the departure point of these efforts is the existing version of a product or technology, an analog, or a competitor’s solution. In professional practice, prior art design is represented by a 3D CAD model. Following the ideas of the design team, the model is modified, and new versions of the design are discussed, tested and selected for further detailed development. The process of ideation is basically nonsystematic and time-consuming, the results are unexpected, but their value is very high: an excellent conceptual idea can make the whole design functionally successful and dramatically reduce the cost of the product and its manufacturing. This dissertation presents an approach to automate the stage of ideation and concept development. The input for this method is a 3D CAD model of an existing design, and the outputs are new design ideas that can also be presented as CAD models.

The Theory of Inventive Problem Solving (further TRIZ) provides most of the theoretical background for the new method. TRIZ tools are combined with a basic CAD modeling framework that is then further adapted and developed. A multi-criteria decision making (MCDM) procedure is added to assist quantitative selection over the set of generated design concepts. More specifically, the method uses a CAD model or sketch of the prior art design to develop its function model, then generates some new function models for a simplified design and, finally, assists in the quantitative evaluation of new designs to select the most appropriate one. Thus, the novelty of the presented work is in the integration and development of TRIZ, CAD and MCDM tools. A new method for automated CAD model complexity reduction is also proposed.

The research results enable further development of a new type of CAD software and merge professional, rigorous geometry-based design methodology and creative design tools. Once this new CAD software becomes commercially available, its systematic ideation methods will assist even those industrial design engineers who do not have much knowledge of them. Until that time, however, more work is required in programming and adapting the new tool to electronics, construction, aero/fluid dynamics and other domains.